Added solver & optimized state.

Positions are kept by index only.

.gitignore

@@ -8,3 +8,4 @@ rice-box.go
 
 # Application
 cmd/krampus19/res/_sandbox/
+cmd/krampus19/TODO

README.md

@@ -0,0 +1,356 @@
+# Sokodragon
+
+This game was made for RmBeer, his wishlist:
+```
+1) DRAGONS!!! HUNDREDS AND HUNDREDS, NO, THOUSANDS OF DRAGONS!!!!!! I LOVE DRAGONS AND I WANT SEE ALL!!!!! I WANT A DRAGON LIKE THE MAIN CHARACTER!!!!! \o/
+2) Include morbid scenes, gores or bloody, where humans are destroyed as part of the game. ^^
+3) Make a good story for the game! :D
+4) That is an action game, strategy, or logical problem, can be any of the 3 or all the 3. I like games to think and solve, because they are more challenging. :) (no like puzzle with part of images and no like questions games)
+
+It may be difficult to create 1000 dragons, I settle for one or some if it's difficult for you. :)
+```
+
+Safe to say I failed miserably to meet the requirements. The game features a single dragon and it is a puzzle game which satifies rules 1) and 4). The idea was to let the dragon have to get to a human/villain type (instead of the egg now) but drawing this was too challenging. Didn't think about a good story yet. Nevertheless: I hope you enjoy solving the 4 puzzles added.
+
+## Building
+Prerequisites:
+- [Allegro](https://liballeg.org/) 5.2 (development libraries).
+- [Go](https://golang.org/dl/) 1.12 or later.
+- GCC.
+- Git.
+
+With all prequisites installed you can run:
+```
+go get -u opslag.de/schobers/krampus19/cmd/krampus19
+```
+
+The generated binary can be found in `$GOPATH/bin` and will depend on the dynamic runtimes and the resources found in `$GOPATH/src/opslag.de/schobers/krampus19/cmd/krampus19/res`.
+
+### Sources
+Can be found at https://opslag.de/schobers/krampus19 (Git repository).
+
+### Embedding resources
+```
+go get -u github.com/GeertJohan/go.rice/rice
+go get -u opslag.de/schobers/krampus19/cmd/krampus19
+go generate opslag.de/schobers/krampus19/cmd/krampus19
+go install opslag.de/schobers/krampus19/cmd/krampus19
+```
+
+Note that `go get` of the `rice` tool is only required once.
+
+### Usefull flags
+`go install` can be executed with the following flags (on Windows):
+- `-tags "static"`: to link against Allegro statically.
+- `-tags "console"`: to show the console output in stdout.
+- `-ldflags "-s -w"`: to reduce the binary size.
+
+Example:
+```
+go install -tags "static console" -ldflags "-s -w" opslag.de/schobers/krampus19/cmd/krampus19
+```
+
+## Settings
+
+- Video settings are only taken into account when the game is restarted. The resolution only applies to fullscreen mode (the "Windowed" setting must be unchecked).
+
+## Licenses
+### Fira Mono font
+
+Copyright (c) 2012-2013, The Mozilla Corporation and Telefonica S.A.
+
+This Font Software is licensed under the SIL Open Font License, Version 1.1.
+This license is copied below, and is also available with a FAQ at:
+http://scripts.sil.org/OFL
+
+
+-----------------------------------------------------------
+SIL OPEN FONT LICENSE Version 1.1 - 26 February 2007
+-----------------------------------------------------------
+
+PREAMBLE
+The goals of the Open Font License (OFL) are to stimulate worldwide
+development of collaborative font projects, to support the font creation
+efforts of academic and linguistic communities, and to provide a free and
+open framework in which fonts may be shared and improved in partnership
+with others.
+
+The OFL allows the licensed fonts to be used, studied, modified and
+redistributed freely as long as they are not sold by themselves. The
+fonts, including any derivative works, can be bundled, embedded, 
+redistributed and/or sold with any software provided that any reserved
+names are not used by derivative works. The fonts and derivatives,
+however, cannot be released under any other type of license. The
+requirement for fonts to remain under this license does not apply
+to any document created using the fonts or their derivatives.
+
+DEFINITIONS
+"Font Software" refers to the set of files released by the Copyright
+Holder(s) under this license and clearly marked as such. This may
+include source files, build scripts and documentation.
+
+"Reserved Font Name" refers to any names specified as such after the
+copyright statement(s).
+
+"Original Version" refers to the collection of Font Software components as
+distributed by the Copyright Holder(s).
+
+"Modified Version" refers to any derivative made by adding to, deleting,
+or substituting -- in part or in whole -- any of the components of the
+Original Version, by changing formats or by porting the Font Software to a
+new environment.
+
+"Author" refers to any designer, engineer, programmer, technical
+writer or other person who contributed to the Font Software.
+
+PERMISSION & CONDITIONS
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of the Font Software, to use, study, copy, merge, embed, modify,
+redistribute, and sell modified and unmodified copies of the Font
+Software, subject to the following conditions:
+
+1) Neither the Font Software nor any of its individual components,
+in Original or Modified Versions, may be sold by itself.
+
+2) Original or Modified Versions of the Font Software may be bundled,
+redistributed and/or sold with any software, provided that each copy
+contains the above copyright notice and this license. These can be
+included either as stand-alone text files, human-readable headers or
+in the appropriate machine-readable metadata fields within text or
+binary files as long as those fields can be easily viewed by the user.
+
+3) No Modified Version of the Font Software may use the Reserved Font
+Name(s) unless explicit written permission is granted by the corresponding
+Copyright Holder. This restriction only applies to the primary font name as
+presented to the users.
+
+4) The name(s) of the Copyright Holder(s) or the Author(s) of the Font
+Software shall not be used to promote, endorse or advertise any
+Modified Version, except to acknowledge the contribution(s) of the
+Copyright Holder(s) and the Author(s) or with their explicit written
+permission.
+
+5) The Font Software, modified or unmodified, in part or in whole,
+must be distributed entirely under this license, and must not be
+distributed under any other license. The requirement for fonts to
+remain under this license does not apply to any document created
+using the Font Software.
+
+TERMINATION
+This license becomes null and void if any of the above conditions are
+not met.
+
+DISCLAIMER
+THE FONT SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT
+OF COPYRIGHT, PATENT, TRADEMARK, OR OTHER RIGHT. IN NO EVENT SHALL THE
+COPYRIGHT HOLDER BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+INCLUDING ANY GENERAL, SPECIAL, INDIRECT, INCIDENTAL, OR CONSEQUENTIAL
+DAMAGES, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF THE USE OR INABILITY TO USE THE FONT SOFTWARE OR FROM
+OTHER DEALINGS IN THE FONT SOFTWARE.
+
+### Open Sans font
+
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
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+      any Contribution intentionally submitted for inclusion in the Work
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+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
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+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
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+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

alui/button.go

@@ -14,6 +14,12 @@ type Button struct {
 	TextAlign allg5.HorizontalAlignment
 }
 
+func NewButton(text string, onClick func()) *Button {
+	b := &Button{Text: text}
+	b.OnClick = onClick
+	return b
+}
+
 func (b *Button) DesiredSize(ctx *Context) geom.PointF32 {
 	font := ctx.Fonts.Get(b.Font)
 	w := font.TextWidth(b.Text)

alui/center.go

@@ -0,0 +1,23 @@
+package alui
+
+import (
+	"opslag.de/schobers/geom"
+)
+
+type center struct {
+	Proxy
+}
+
+func Center(control Control) Control {
+	return &center{Proxy: Proxy{Target: control}}
+}
+
+func (c *center) Layout(ctx *Context, bounds geom.RectangleF32) {
+	size := c.DesiredSize(ctx)
+	center := bounds.Center()
+
+	size.X = geom.Min32(size.X, bounds.Dx())
+	size.Y = geom.Min32(size.Y, bounds.Dy())
+	size = size.Mul(.5)
+	c.Proxy.Layout(ctx, geom.RectF32(center.X-size.X, center.Y-size.Y, center.X+size.X, center.Y+size.Y))
+}

alui/column.go

@@ -0,0 +1,34 @@
+package alui
+
+import "opslag.de/schobers/geom"
+
+type Column struct {
+	Proxy
+
+	panel *StackPanel
+}
+
+func NewColumn() *Column {
+	c := &Column{}
+	c.Init()
+	return c
+}
+
+func (c *Column) AddChild(child ...Control) {
+	c.panel.Children = append(c.panel.Children, child...)
+}
+
+func (c *Column) Init() {
+	c.panel = &StackPanel{Orientation: OrientationVertical}
+	c.Proxy.Target = c.panel
+}
+
+func (c *Column) Layout(ctx *Context, bounds geom.RectangleF32) {}
+
+func (c *Column) Render(ctx *Context, bounds geom.RectangleF32) {
+	columnHeight := c.Proxy.DesiredSize(ctx).Y
+	width, center := bounds.Dx(), bounds.Center()
+	columnBounds := geom.RectF32(.25*width, center.Y-.5*columnHeight, .75*width, center.Y+.5*columnHeight)
+	c.Proxy.Layout(ctx, columnBounds)
+	c.Proxy.Render(ctx, columnBounds)
+}

alui/container.go

@@ -11,11 +11,8 @@ type Container struct {
 	Children []Control
 }
 
-func (c *Container) Handle(e allg5.Event) {
-	c.ControlBase.Handle(e)
-	for _, child := range c.Children {
-		child.Handle(e)
-	}
+func (c *Container) AddChild(child ...Control) {
+	c.Children = append(c.Children, child...)
 }
 
 func (c *Container) DesiredSize(ctx *Context) geom.PointF32 {
@@ -36,6 +33,13 @@ func (c *Container) DesiredSize(ctx *Context) geom.PointF32 {
 	return size
 }
 
+func (c *Container) Handle(e allg5.Event) {
+	c.ControlBase.Handle(e)
+	for _, child := range c.Children {
+		child.Handle(e)
+	}
+}
+
 func (c *Container) Layout(ctx *Context, bounds geom.RectangleF32) {
 	c.ControlBase.Layout(ctx, bounds)
 	for _, child := range c.Children {

alui/fonts.go

@@ -44,7 +44,7 @@ func (f *Fonts) DrawAlignFont(font *allg5.Font, left, top, right float32, color
 		font.Draw(right, top, color, allg5.AlignRight, text)
 	default:
 		left, top = geom.Round32(left), geom.Round32(top)
-		font.Draw(left, top, color, allg5.AlignRight, text)
+		font.Draw(left, top, color, allg5.AlignLeft, text)
 	}
 }
 

alui/label.go

@@ -10,7 +10,8 @@ var _ Control = &Label{}
 type Label struct {
 	ControlBase
 
-	Text string
+	Text      string
+	TextAlign allg5.HorizontalAlignment
 }
 
 func (l *Label) DesiredSize(ctx *Context) geom.PointF32 {
@@ -29,5 +30,5 @@ func (l *Label) Render(ctx *Context, bounds geom.RectangleF32) {
 	if back != nil {
 		allg5.DrawFilledRectangle(bounds.Min.X, bounds.Min.Y, bounds.Max.X, bounds.Max.Y, *back)
 	}
-	ctx.Fonts.Draw(l.Font, bounds.Min.X+4, bounds.Min.Y+4, *fore, l.Text)
+	ctx.Fonts.DrawAlign(l.Font, bounds.Min.X+4, bounds.Min.Y+4, bounds.Max.X-4, *fore, l.TextAlign, l.Text)
 }

alui/margins.go

@@ -0,0 +1,53 @@
+package alui
+
+import (
+	"opslag.de/schobers/geom"
+)
+
+var _ Control = &Margins{}
+
+type Margins struct {
+	Proxy
+
+	Top, Left, Bottom, Right float32
+
+	bounds geom.RectangleF32
+}
+
+func NewMargins(target Control, margins ...float32) *Margins {
+	m := &Margins{Proxy: Proxy{Target: target}}
+	switch len(margins) {
+	case 1:
+		m.Top, m.Left, m.Bottom, m.Right = margins[0], margins[0], margins[0], margins[0]
+	case 2:
+		m.Top, m.Left, m.Bottom, m.Right = margins[0], margins[1], margins[0], margins[1]
+	case 3:
+		m.Top, m.Left, m.Bottom, m.Right = margins[0], margins[1], margins[2], margins[1]
+	case 4:
+		m.Top, m.Left, m.Bottom, m.Right = margins[0], margins[1], margins[2], margins[3]
+	default:
+		panic("expected 1 (all same), 2 (vertical, horizontal), 3 (top, horizontal, bottom) or 4 margins (all separately specified)")
+	}
+	return m
+}
+
+func (m *Margins) Bounds() geom.RectangleF32 { return m.bounds }
+
+func (m *Margins) DesiredSize(ctx *Context) geom.PointF32 {
+	return m.Proxy.DesiredSize(ctx).Add2D(m.Left+m.Right, m.Top+m.Bottom)
+}
+
+func (m *Margins) inset(bounds geom.RectangleF32) geom.RectangleF32 {
+	return geom.RectF32(bounds.Min.X+m.Left, bounds.Min.Y+m.Top, bounds.Max.X-m.Right, bounds.Max.Y-m.Bottom)
+}
+
+func (m *Margins) Layout(ctx *Context, bounds geom.RectangleF32) {
+	m.bounds = bounds
+	target := m.inset(bounds)
+	m.Proxy.Layout(ctx, target)
+}
+
+func (m *Margins) Render(ctx *Context, bounds geom.RectangleF32) {
+	target := m.inset(bounds)
+	m.Proxy.Render(ctx, target)
+}

alui/menu.go

@@ -2,13 +2,13 @@ package alui
 
 import (
 	"opslag.de/schobers/allg5"
-	"opslag.de/schobers/geom"
 )
 
 type Menu struct {
-	Proxy
+	Column
+
+	OnEscape func()
 
-	panel   *StackPanel
 	active  int
 	buttons []*Button
 }
@@ -19,11 +19,6 @@ func NewMenu() *Menu {
 	return m
 }
 
-func (m *Menu) Init() {
-	m.panel = &StackPanel{Orientation: OrientationVertical}
-	m.Proxy.Target = m.panel
-}
-
 func (m *Menu) Activate(i int) {
 	if len(m.buttons) == 0 || i < 0 {
 		return
@@ -42,17 +37,24 @@ func (m *Menu) Add(text string, onClick func()) {
 		button.Over = true
 	}
 	m.buttons = append(m.buttons, button)
-	m.panel.Children = append(m.panel.Children, button)
+	m.AddChild(button)
 }
 
 func (m *Menu) Handle(e allg5.Event) {
-	m.Proxy.Handle(e)
+	m.Column.Handle(e)
 
 	if len(m.buttons) == 0 {
 		return
 	}
 
 	switch e := e.(type) {
+	case *allg5.KeyDownEvent:
+		switch e.KeyCode {
+		case allg5.KeyEscape:
+			if onEscape := m.OnEscape; onEscape != nil {
+				onEscape()
+			}
+		}
 	case *allg5.KeyCharEvent:
 		switch e.KeyCode {
 		case allg5.KeyDown:
@@ -75,16 +77,6 @@ func (m *Menu) Handle(e allg5.Event) {
 	}
 }
 
-func (m *Menu) Layout(ctx *Context, bounds geom.RectangleF32) {}
-
-func (m *Menu) Render(ctx *Context, bounds geom.RectangleF32) {
-	menuHeight := m.Proxy.DesiredSize(ctx).Y
-	width, center := bounds.Dx(), bounds.Center()
-	menuBounds := geom.RectF32(.25*width, center.Y-.5*menuHeight, .75*width, center.Y+.5*menuHeight)
-	m.Proxy.Layout(ctx, menuBounds)
-	m.Proxy.Render(ctx, menuBounds)
-}
-
 func (m *Menu) updateActiveButton(active int) {
 	m.active = active
 	for i, btn := range m.buttons {

alui/proxy.go

@@ -31,14 +31,14 @@ func (p *Proxy) Handle(e allg5.Event) {
 	}
 }
 
-func (p *Proxy) Render(ctx *Context, bounds geom.RectangleF32) {
-	if p.Target != nil {
-		p.Target.Render(ctx, bounds)
-	}
-}
-
 func (p *Proxy) Layout(ctx *Context, bounds geom.RectangleF32) {
 	if p.Target != nil {
 		p.Target.Layout(ctx, bounds)
 	}
 }
+
+func (p *Proxy) Render(ctx *Context, bounds geom.RectangleF32) {
+	if p.Target != nil {
+		p.Target.Render(ctx, bounds)
+	}
+}

alui/stackpanel.go

@@ -13,10 +13,6 @@ type StackPanel struct {
 	Orientation Orientation
 }
 
-func (s *StackPanel) Handle(e allg5.Event) {
-	s.Container.Handle(e)
-}
-
 func (s *StackPanel) asLength(p geom.PointF32) float32 {
 	switch s.Orientation {
 	case OrientationHorizontal:
@@ -75,6 +71,10 @@ func (s *StackPanel) DesiredSize(ctx *Context) geom.PointF32 {
 	return size
 }
 
+func (s *StackPanel) Handle(e allg5.Event) {
+	s.Container.Handle(e)
+}
+
 func (s *StackPanel) Layout(ctx *Context, bounds geom.RectangleF32) {
 	s.Container.Layout(ctx, bounds)
 

cmd/krampus19/animations.go

@@ -0,0 +1,127 @@
+package main
+
+import (
+	"math"
+	"math/rand"
+	"time"
+
+	"opslag.de/schobers/geom"
+)
+
+type moveAnimation struct {
+	e        *entity
+	from, to geom.Point
+	pos      geom.PointF32
+}
+
+func newMoveAnimation(e *entity, from, to geom.Point) *moveAnimation {
+	ani := &moveAnimation{e: e, from: from, to: to, pos: from.ToF32()}
+	return ani
+}
+
+func (a *moveAnimation) Animate(start, now time.Duration) bool {
+	const duration = 210 * time.Millisecond
+
+	progress := float32((now-start)*1000/duration) * .001
+	from, to := a.from.ToF32(), a.to.ToF32()
+	if progress >= 1 {
+		a.e.scr.pos = to
+		return false
+	}
+	a.e.scr.pos = to.Sub(from).Mul(progress).Add(from)
+	return true
+}
+
+type sinkAnimation struct {
+	e *entity
+}
+
+func newSinkAnimation(e *entity) *sinkAnimation {
+	return &sinkAnimation{e: e}
+}
+
+func (a *sinkAnimation) Animate(start, now time.Duration) bool {
+	const duration = 70 * time.Millisecond
+
+	progress := float32((now-start)*1000/duration) * .001
+	if progress >= 1 {
+		a.e.scr.z = 80
+		return false
+	}
+	a.e.scr.z = progress * 80
+	return true
+}
+
+type splashAnimation struct {
+	particles []splashParticle
+}
+
+func newSplashAnimation(pos geom.Point) *splashAnimation {
+	pos32 := pos.ToF32()
+	a := &splashAnimation{}
+	n := rand.Intn(20) + 4
+	for i := 0; i < n; i++ {
+		angle := rand.Float32() * math.Pi * 2
+		a.particles = append(a.particles, splashParticle{
+			angle:  angle,
+			origin: pos32.Add2D(.45*geom.Cos32(angle), .45*geom.Sin32(angle)), // [-0.45 .. 0.45]
+			speed:  .5*math.Pi + 2*math.Pi*rand.Float32(),                     // [0.5*Pi .. 2.5*Pi)
+			height: .2 + .8*rand.Float32(),                                    // [0.2 .. 1.0)
+			dist:   .5 + .5*rand.Float32(),                                    // [0.5 .. 1.0)
+		})
+	}
+	return a
+}
+
+func (a *splashAnimation) Animate(start, now time.Duration) bool {
+	const duration = 1670 * time.Millisecond
+
+	progress := float32((now-start)*1000/duration) * .001
+	var opaq float32 = 1
+	if progress > .6 {
+		if progress > 1 {
+			opaq = 0
+		} else {
+			opaq = 2.5 - 2.5*progress
+		}
+	}
+	for i, p := range a.particles {
+		progress := geom.Min32(math.Pi, progress*p.speed) / math.Pi
+		a.particles[i].part = particle{
+			opaq: opaq,
+			pos:  p.origin.Add2D(progress*p.dist*geom.Cos32(p.angle), progress*p.dist*geom.Sin32(p.angle)),
+			z:    20 + p.height*-100*geom.Sin32(progress*math.Pi),
+		}
+	}
+	if progress > 1 {
+		return false
+	}
+	return true
+}
+
+type particle struct {
+	pos  geom.PointF32
+	z    float32
+	opaq float32
+}
+
+func splitParticles(y float32, particles []particle) (behind []particle, front []particle) {
+	for _, p := range particles {
+		if p.pos.Y > y {
+			front = append(front, p)
+		} else {
+			behind = append(behind, p)
+		}
+	}
+	return
+}
+
+type splashParticle struct {
+	origin geom.PointF32
+	angle  float32
+	speed  float32
+	height float32
+	dist   float32
+
+	part particle
+}

cmd/krampus19/changesettings.go

@@ -0,0 +1,315 @@
+package main
+
+import (
+	"fmt"
+	"log"
+
+	"opslag.de/schobers/krampus19/gut"
+
+	"opslag.de/schobers/geom"
+
+	"opslag.de/schobers/allg5"
+	"opslag.de/schobers/krampus19/alui"
+)
+
+const margin = 8
+
+type displayModeControl struct {
+	alui.StackPanel
+
+	label alui.Label
+
+	modes   []string
+	current int
+}
+
+func newDisplayModeControl(ctx *Context) *displayModeControl {
+	var modes []string
+	fmtDisplayMode := func(width, height int) string { return fmt.Sprintf("%d x %d", width, height) }
+	containsDisplayMode := func(mode string) bool {
+		for _, m := range modes {
+			if m == mode {
+				return true
+			}
+		}
+		return false
+	}
+
+	displayMode := ctx.Settings.Video.DisplayMode
+	if displayMode == "" {
+		displayMode = fmtDisplayMode(ctx.DisplaySize.X, ctx.DisplaySize.Y)
+	}
+	var current int
+	for _, m := range allg5.DisplayModes() {
+		mode := fmtDisplayMode(m.Width, m.Height)
+		if containsDisplayMode(mode) {
+			continue
+		}
+		if mode == displayMode {
+			current = len(modes)
+		}
+		modes = append(modes, mode)
+	}
+
+	c := &displayModeControl{modes: modes, current: current}
+	c.Orientation = alui.OrientationHorizontal
+	c.label.TextAlign = allg5.AlignCenter
+	c.selectMode(0)
+
+	c.AddChild(newSpriteButton(ctx, "ui", "angle-left", func() { c.selectMode(-1) }))
+	c.AddChild(&c.label)
+	c.AddChild(newSpriteButton(ctx, "ui", "angle-right", func() { c.selectMode(1) }))
+	return c
+}
+
+func (c *displayModeControl) selectMode(delta int) {
+	c.current = (c.current + delta + len(c.modes)) % len(c.modes)
+	c.label.Text = c.Mode()
+}
+
+func (c *displayModeControl) Mode() string { return c.modes[c.current] }
+
+type checkBox struct {
+	alui.Button
+
+	ctx *Context
+
+	Selected bool
+}
+
+func newCheckBox(ctx *Context) *checkBox {
+	b := &checkBox{ctx: ctx}
+	b.OnClick = func() {
+		b.Selected = !b.Selected
+	}
+	return b
+}
+
+func (b *checkBox) DesiredSize(ctx *alui.Context) geom.PointF32 {
+	return b.ctx.SpriteDrawer.Size("ui", "check-square").Add2D(2*margin, 2*margin)
+}
+
+func (b *checkBox) Render(ctx *alui.Context, bounds geom.RectangleF32) {
+	tint := b.ctx.Palette.Primary
+	if b.Over {
+		tint = b.ctx.Palette.Dark
+		ctx.Cursor = allg5.MouseCursorLink
+	}
+	var part = "square"
+	if b.Selected {
+		part = "check-square"
+	}
+	b.ctx.SpriteDrawer.Draw("ui", part, bounds.Center(), DrawSpriteOptions{Tint: &tint})
+}
+
+type spriteButton struct {
+	alui.Button
+
+	ctx *Context
+
+	Sprite string
+	Part   string
+}
+
+func newSpriteButton(ctx *Context, sprite, part string, onClick func()) *spriteButton {
+	b := &spriteButton{ctx: ctx, Sprite: sprite, Part: part}
+	b.OnClick = onClick
+	return b
+}
+
+func (b *spriteButton) DesiredSize(ctx *alui.Context) geom.PointF32 {
+	return b.ctx.SpriteDrawer.Size(b.Sprite, b.Part).Add2D(2*margin, 2*margin)
+}
+
+func (b *spriteButton) Render(ctx *alui.Context, bounds geom.RectangleF32) {
+	tint := b.ctx.Palette.Primary
+	if b.Over {
+		tint = b.ctx.Palette.Dark
+		ctx.Cursor = allg5.MouseCursorLink
+	}
+	b.ctx.SpriteDrawer.Draw(b.Sprite, b.Part, bounds.Center(), DrawSpriteOptions{Tint: &tint})
+}
+
+type selectKeyControl struct {
+	alui.Label
+
+	Key allg5.Key
+
+	WaitingForInput bool
+}
+
+func newSelectKeyControl(key allg5.Key) *selectKeyControl {
+	c := &selectKeyControl{Key: key}
+	c.TextAlign = allg5.AlignCenter
+	return c
+}
+
+func (c *selectKeyControl) Handle(e allg5.Event) {
+	c.Label.Handle(e)
+
+	switch e := e.(type) {
+	case *allg5.MouseButtonDownEvent:
+		if c.Over && e.Button == allg5.MouseButtonLeft {
+			c.WaitingForInput = true
+		}
+	case *allg5.KeyDownEvent:
+		if c.WaitingForInput {
+			if e.KeyCode != allg5.KeyEscape {
+				c.Key = e.KeyCode
+			}
+			c.WaitingForInput = false
+		}
+	}
+}
+
+func (c *selectKeyControl) Render(ctx *alui.Context, bounds geom.RectangleF32) {
+	if c.WaitingForInput {
+		c.Text = "_"
+	} else {
+		c.Text = gut.KeyToString(c.Key)
+	}
+	if c.Over {
+		ctx.Cursor = allg5.MouseCursorLink
+	}
+	c.Label.Render(ctx, bounds)
+}
+
+type settingsHeader struct {
+	alui.Label
+}
+
+func newSettingsHeader(label string) alui.Control {
+	header := &settingsHeader{}
+	header.Font = "header"
+	header.Text = label
+	return alui.NewMargins(header, 3*margin, 0, 2*margin)
+}
+
+type settingsRow struct {
+	alui.StackPanel
+
+	label *alui.Label
+	edit  alui.Control
+}
+
+func newSettingRow(label string, edit alui.Control) *settingsRow {
+	row := &settingsRow{}
+	row.Orientation = alui.OrientationHorizontal
+	row.label = &alui.Label{Text: label}
+	row.edit = edit
+	row.Children = append(row.Children, row.label, row.edit)
+	return row
+}
+
+func (r *settingsRow) Layout(ctx *alui.Context, bounds geom.RectangleF32) {
+	label := bounds
+	label.Max.X = label.Min.X + .5*label.Dx()
+	r.label.Layout(ctx, label)
+
+	width := r.edit.DesiredSize(ctx).X
+	edit := bounds
+	if geom.IsNaN32(width) || width > label.Dx() {
+		edit.Min.X = label.Max.X
+	} else {
+		margin := (label.Dx() - width) * .5
+		edit.Min.X = label.Max.X + margin
+		edit.Max.X -= margin
+	}
+	r.edit.Layout(ctx, edit)
+}
+
+type wideButton struct {
+	alui.Button
+}
+
+func newWideButton(label string, onClick func()) *wideButton {
+	b := &wideButton{}
+	b.Text = label
+	b.TextAlign = allg5.AlignCenter
+	b.OnClick = onClick
+	return b
+}
+
+func (b *wideButton) DesiredSize(ctx *alui.Context) geom.PointF32 {
+	size := b.Button.DesiredSize(ctx)
+	size.X += 2 * margin
+	return size
+}
+
+type changeSettings struct {
+	alui.Column
+
+	ctx *Context
+
+	rows   []*settingsRow
+	active int
+}
+
+func (s *changeSettings) addRow(row ...*settingsRow) {
+	for _, row := range row {
+		s.AddChild(row)
+		s.rows = append(s.rows, row)
+	}
+}
+
+func (s *changeSettings) Enter(ctx *Context) error {
+	s.Init()
+	s.ctx = ctx
+
+	keyLeft := newSelectKeyControl(s.ctx.Settings.Controls.MoveLeft)
+	keyUp := newSelectKeyControl(s.ctx.Settings.Controls.MoveUp)
+	keyRight := newSelectKeyControl(s.ctx.Settings.Controls.MoveRight)
+	keyDown := newSelectKeyControl(s.ctx.Settings.Controls.MoveDown)
+
+	s.AddChild(newSettingsHeader("Controls"))
+	s.addRow(
+		newSettingRow("Key left", keyLeft),
+		newSettingRow("Key up", keyUp),
+		newSettingRow("Key right", keyRight),
+		newSettingRow("Key down", keyDown),
+	)
+	s.AddChild(newSettingsHeader("Video"))
+
+	displayMode := newDisplayModeControl(ctx)
+	windowed := newCheckBox(ctx)
+	windowed.Selected = s.ctx.Settings.Video.Windowed
+
+	s.addRow(
+		newSettingRow("Windowed", windowed),
+		newSettingRow("Resolution (fullscreen)", displayMode),
+	)
+	buttons := &alui.StackPanel{Orientation: alui.OrientationHorizontal}
+	buttons.AddChild(
+		newWideButton("Cancel", func() { s.ctx.Navigation.ShowMainMenu() }),
+		newWideButton("OK", func() {
+			var controls = controls{MoveLeft: keyLeft.Key, MoveUp: keyUp.Key, MoveRight: keyRight.Key, MoveDown: keyDown.Key}
+			var video = video{Windowed: windowed.Selected, DisplayMode: displayMode.Mode()}
+			s.ctx.Settings = settings{Controls: controls, Video: video}
+			err := s.ctx.Settings.StoreDefault()
+			if err != nil {
+				log.Printf("User settings are not stored: %v", err)
+			} else {
+				log.Printf("Stored new settings.")
+			}
+
+			s.ctx.Navigation.ShowMainMenu()
+		}),
+	)
+	s.AddChild(alui.Center(buttons))
+	return nil
+}
+
+func (s *changeSettings) Handle(e allg5.Event) {
+	s.Column.Handle(e)
+
+	switch e := e.(type) {
+	case *allg5.KeyDownEvent:
+		switch e.KeyCode {
+		case allg5.KeyEscape:
+			s.ctx.Navigation.ShowMainMenu()
+		}
+	}
+}
+
+func (s *changeSettings) Leave() {
+}

cmd/krampus19/console.go

@@ -63,7 +63,7 @@ func (c *console) Render(ctx *alui.Context, bounds geom.RectangleF32) {
 		}
 		messageTop := size.Y - totalHeight - c.offset
 		for _, m := range messages {
-			if messageTop <= size.Y || (messageTop+lineHeight) >= 0 {
+			if messageTop <= size.Y && (messageTop+lineHeight) >= 0 {
 				ctx.Fonts.DrawFont(font, 0, messageTop, ctx.Palette.Text, m)
 			}
 			messageTop += lineHeight

cmd/krampus19/context.go

@@ -3,6 +3,8 @@ package main
 import (
 	"time"
 
+	"github.com/spf13/afero"
+	"opslag.de/schobers/geom"
 	"opslag.de/schobers/krampus19/alui"
 
 	"opslag.de/schobers/allg5"
@@ -20,12 +22,16 @@ func newTexture(bmp *allg5.Bitmap) texture {
 }
 
 type Context struct {
-	Resources vfs.CopyDir
-	Textures  map[string]texture
-	Levels    map[string]level
-	Sprites   map[string]sprite
-	Settings  settings
-	Palette   *alui.Palette
+	DisplaySize  geom.Point
+	Resources    vfs.CopyDir
+	ResourcesFs  afero.Fs
+	Textures     map[string]texture
+	Sprites      map[string]sprite
+	Levels       *levelPacks
+	Progress     progress
+	SpriteDrawer SpriteDrawer
+	Settings     settings
+	Palette      *alui.Palette
 
 	Tick       time.Duration
 	Navigation navigation

cmd/krampus19/entity.go

@@ -0,0 +1,21 @@
+package main
+
+import (
+	"opslag.de/schobers/geom"
+	"opslag.de/schobers/krampus19/soko"
+)
+
+type entity struct {
+	id  int
+	typ soko.EntityType
+	scr entityLoc
+}
+
+type entityLoc struct {
+	pos geom.PointF32
+	z   float32
+}
+
+func newEntity(e soko.Entity, pos geom.Point) *entity {
+	return &entity{e.ID, e.Typ, entityLoc{pos.ToF32(), 0}}
+}

cmd/krampus19/entitymap.go

@@ -0,0 +1,25 @@
+package main
+
+import "sort"
+
+type entityMap map[int]*entity
+
+func (m entityMap) RenderOrder() []*entity {
+	entities := make([]*entity, 0, len(m))
+	for _, e := range m {
+		entities = append(entities, e)
+	}
+
+	sort.Slice(entities, func(i, j int) bool {
+		var posI, posJ = entities[i].scr.pos, entities[j].scr.pos
+		if posI.Y == posJ.Y {
+			if posI.X == posJ.X {
+				return entities[i].id < entities[j].id
+			}
+			return posI.X < posJ.X
+		}
+		return posI.Y < posJ.Y
+	})
+
+	return entities
+}

cmd/krampus19/game.go

@@ -4,10 +4,16 @@ import (
 	"errors"
 	"fmt"
 	"image/png"
+	"io"
 	"log"
+	"os"
+	"path/filepath"
+	"strings"
 
+	"github.com/spf13/afero"
 	"opslag.de/schobers/allg5"
 	"opslag.de/schobers/fs/vfs"
+	"opslag.de/schobers/geom"
 	"opslag.de/schobers/krampus19/alui"
 	"opslag.de/schobers/krampus19/gut"
 )
@@ -23,7 +29,7 @@ type game struct {
 }
 
 func (g *game) initUI(disp *allg5.Display, cons *gut.Console, fps *gut.FPS) error {
-	disp.SetWindowTitle("Krampushack '19 - Title TBD - by Tharro")
+	disp.SetWindowTitle("Krampushack '19 - Sokodragon - by Tharro")
 	ui := alui.NewUI(disp, &g.main)
 	ui.SetPalette(alui.Palette{
 		Icon:    allg5.NewColor(0x21, 0x21, 0x21),
@@ -59,7 +65,11 @@ func (g *game) loadBitmap(path, name string) error {
 }
 
 func (g *game) loadFonts() error {
-	openSansPath, err := g.ctx.Resources.Retrieve("fonts/OpenSans-Regular.ttf")
+	openSansRegularPath, err := g.ctx.Resources.Retrieve("fonts/OpenSans-Regular.ttf")
+	if err != nil {
+		return err
+	}
+	openSansBoldPath, err := g.ctx.Resources.Retrieve("fonts/OpenSans-Bold.ttf")
 	if err != nil {
 		return err
 	}
@@ -67,7 +77,11 @@ func (g *game) loadFonts() error {
 	if err != nil {
 		return err
 	}
-	err = g.ui.Fonts().LoadFonts(alui.FontDescription{Path: openSansPath, Name: "default", Size: 36})
+	err = g.ui.Fonts().LoadFonts(alui.FontDescription{Path: openSansRegularPath, Name: "default", Size: 32})
+	if err != nil {
+		return err
+	}
+	err = g.ui.Fonts().LoadFonts(alui.FontDescription{Path: openSansBoldPath, Name: "header", Size: 32})
 	if err != nil {
 		return err
 	}
@@ -88,21 +102,57 @@ func (g *game) loadTextures(pathToName map[string]string) error {
 	return nil
 }
 
-func (g *game) loadLevels(names ...string) error {
-	g.ctx.Levels = map[string]level{}
-	for _, name := range names {
-		fileName := fmt.Sprintf("levels/level%s.txt", name)
-		f, err := g.ctx.Resources.Open(fileName)
+func (g *game) loadLevelPacks() error {
+	g.ctx.Levels = newLevelPacks()
+
+	var ids []string
+	const root = "levels"
+	err := afero.Walk(g.ctx.ResourcesFs, root, func(path string, info os.FileInfo, err error) error {
 		if err != nil {
 			return err
 		}
-		defer f.Close()
-		level, err := loadLevelAsset(f)
-		if err != nil {
-			return err
+		if !info.IsDir() {
+			return nil
 		}
-		g.ctx.Levels[name] = level
+		name := filepath.Base(path)
+		if name == root {
+			return nil
+		}
+
+		if !strings.HasPrefix(name, "pack") {
+			return filepath.SkipDir
+		}
+		ids = append(ids, name[4:])
+		return filepath.SkipDir
+	})
+	if err != nil {
+		return err
 	}
+
+	for _, id := range ids {
+		err := g.loadLevelPack(id)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (g *game) loadLevelPack(id string) error {
+	fileName := fmt.Sprintf("levels/pack%s/info.txt", id)
+	f, err := g.ctx.Resources.Open(fileName)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	pack, err := parseLevelPackAsset(f, func(levelID string) (io.ReadCloser, error) {
+		fileName := fmt.Sprintf("levels/pack%s/level%s.txt", id, levelID)
+		return g.ctx.Resources.Open(fileName)
+	})
+	if err != nil {
+		return err
+	}
+	g.ctx.Levels.Add(id, pack)
 	return nil
 }
 
@@ -136,27 +186,27 @@ func (g *game) loadSprites(names ...string) error {
 func (g *game) loadAssets() error {
 	log.Println("Loading textures...")
 	err := g.loadTextures(map[string]string{
-		"basic_tile.png":        "basic_tile",
-		"sunken_brick_tile.png": "sunken_brick_tile",
-		"water_tile.png":        "water_tile",
+		"entity_brick.png":  "brick",
+		"entity_dragon.png": "dragon",
+		"entity_egg.png":    "egg",
 
-		"main_character.png":    "main_character",
-		"villain_character.png": "villain_character",
+		"tile_lava_brick.png": "lava_brick",
+		"tile_magma.png":      "magma",
 
-		"brick.png": "brick",
-		"crate.png": "crate",
+		"particles.png": "particles",
+		"ui.png":        "ui",
 	})
 	if err != nil {
 		return err
 	}
 	log.Printf("Loaded %d textures.\n", len(g.ctx.Textures))
 
-	log.Println("Loading levels...")
-	err = g.loadLevels("1")
+	log.Println("Loading level packs...")
+	err = g.loadLevelPacks()
 	if err != nil {
 		return err
 	}
-	log.Printf("Loaded %d levels.\n", len(g.ctx.Levels))
+	log.Printf("Loaded %d levels packs (%d levels).\n", g.ctx.Levels.Len(), g.ctx.Levels.LenLevels())
 
 	log.Println("Loading fonts...")
 	err = g.loadFonts()
@@ -166,10 +216,10 @@ func (g *game) loadAssets() error {
 	log.Printf("Loaded %d fonts.\n", g.ui.Fonts().Len())
 
 	log.Println("Loading sprites")
-	// err = g.loadSprites("dragon")
-	// if err != nil {
-	// 	return err
-	// }
+	err = g.loadSprites("brick", "dragon", "egg", "lava_brick", "magma", "particles", "ui")
+	if err != nil {
+		return err
+	}
 	log.Printf("Loaded %d sprites.\n", len(g.ctx.Sprites))
 	return nil
 }
@@ -179,9 +229,15 @@ func (g *game) Destroy() {
 	g.ctx.Destroy()
 }
 
-func (g *game) Init(disp *allg5.Display, res vfs.CopyDir, cons *gut.Console, fps *gut.FPS) error {
+func (g *game) Init(disp *allg5.Display, settings settings, res vfs.CopyDir, resFs afero.Fs, cons *gut.Console, fps *gut.FPS) error {
 	log.Print("Initializing game...")
-	g.ctx = &Context{Resources: res, Textures: map[string]texture{}, Settings: newDefaultSettings(), Navigation: navigation{game: g}}
+	g.ctx = &Context{Resources: res, ResourcesFs: resFs, Textures: map[string]texture{}, Settings: settings, Navigation: navigation{game: g}}
+	g.ctx.DisplaySize = geom.Pt(disp.Width(), disp.Height())
+	g.ctx.SpriteDrawer.ctx = g.ctx
+	err := g.ctx.Progress.load()
+	if err != nil {
+		log.Printf("Unable to load previous progress.")
+	}
 	if err := g.initUI(disp, cons, fps); err != nil {
 		return err
 	}
@@ -191,7 +247,7 @@ func (g *game) Init(disp *allg5.Display, res vfs.CopyDir, cons *gut.Console, fps
 	}
 	log.Print("Loaded assets.")
 
-	g.ctx.Navigation.showMainMenu()
+	g.ctx.Navigation.ShowMainMenu()
 
 	return nil
 }

cmd/krampus19/io.go

@@ -0,0 +1,50 @@
+package main
+
+import (
+	"encoding/json"
+	"os"
+	"path/filepath"
+)
+
+func decodeJSON(path string, v interface{}) error {
+	f, err := os.Open(path)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	err = json.NewDecoder(f).Decode(v)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+func encodeJSON(path string, v interface{}) error {
+	f, err := os.Create(path)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	return json.NewEncoder(f).Encode(v)
+}
+
+func userDir() (string, error) {
+	config, err := os.UserConfigDir()
+	if err != nil {
+		return "", err
+	}
+	dir := filepath.Join(config, "krampus19")
+	err = os.MkdirAll(dir, 0777)
+	if err != nil {
+		return "", err
+	}
+	return dir, nil
+}
+
+func userFile(name string) (string, error) {
+	dir, err := userDir()
+	if err != nil {
+		return "", err
+	}
+	return filepath.Join(dir, name), nil
+}

cmd/krampus19/krampus19.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"fmt"
 	"io"
 	"log"
 	"time"
@@ -10,6 +11,7 @@ import (
 	"opslag.de/schobers/allg5"
 	"opslag.de/schobers/fs/ricefs"
 	"opslag.de/schobers/fs/vfs"
+	"opslag.de/schobers/geom"
 	"opslag.de/schobers/krampus19/gut"
 )
 
@@ -22,10 +24,15 @@ func main() {
 	}
 }
 
-func resources() (vfs.CopyDir, error) {
+func resources() (vfs.CopyDir, afero.Fs, error) {
 	var embeddedFs = ricefs.NewFs(rice.MustFindBox("res"))
 	var osFs = afero.NewBasePathFs(afero.NewOsFs(), "./res")
-	return vfs.NewCopyDir(vfs.NewFallbackFs(osFs, embeddedFs))
+	var fs = vfs.NewFallbackFs(osFs, embeddedFs)
+	copy, err := vfs.NewCopyDir(fs)
+	if err != nil {
+		return nil, nil, err
+	}
+	return copy, fs, nil
 }
 
 func run() error {
@@ -33,19 +40,64 @@ func run() error {
 	cons := &gut.Console{}
 	log.SetOutput(io.MultiWriter(log.Writer(), cons))
 
-	log.Printf("Initializing Allegro")
-	err := allg5.Init(allg5.InitAll)
+	res, resFs, err := resources()
+	if err != nil {
+		return err
+	}
+	defer res.Destroy()
+
+	settings := newDefaultSettings()
+	err = settings.LoadDefault()
+	if err != nil {
+		log.Printf("Unable to load settings, falling back on defaults.")
+	}
+	err = settings.StoreDefault()
+	if err != nil {
+		log.Printf("Unable to store settings; err: %v", err)
+	}
+
+	log.Printf("Initializing Allegro.")
+	var init = allg5.InitAll
+	init.Audio = false
+	err = allg5.Init(init)
 	if err != nil {
 		return err
 	}
 
-	log.Printf("Creating display")
-	disp, err := allg5.NewDisplay(1440, 900, allg5.NewDisplayOptions{Maximized: false, Windowed: true, Resizable: true, Vsync: true})
+	log.Printf("Creating display.")
+	var size = geom.Pt(1280, 720)
+	dispOptions := allg5.NewDisplayOptions{Vsync: true, Fullscreen: true}
+	if settings.Video.Windowed {
+		dispOptions.Frameless = true
+		dispOptions.Windowed = true
+	} else {
+		dispOptions.Fullscreen = true
+		str := func(m allg5.DisplayMode) string { return fmt.Sprintf("%d x %d", m.Width, m.Height) }
+		for _, mode := range allg5.DisplayModes() {
+			if str(mode) == settings.Video.DisplayMode {
+				size = geom.Pt(mode.Width, mode.Height)
+			}
+		}
+	}
+	disp, err := allg5.NewDisplay(size.X, size.Y, dispOptions)
 	if err != nil {
 		return err
 	}
 	defer disp.Destroy()
 
+	iconPath, err := res.Retrieve("icon.png")
+	if err != nil {
+		log.Printf("Unable to retrieve icon.")
+	} else {
+		icon, err := allg5.LoadBitmap(iconPath)
+		if err != nil {
+			log.Printf("Unable to load icon bitmap.")
+		} else {
+			defer icon.Destroy()
+			disp.SetIcon(icon)
+		}
+	}
+
 	eq, err := allg5.NewEventQueue()
 	if err != nil {
 		return err
@@ -56,17 +108,11 @@ func run() error {
 	eq.RegisterKeyboard()
 	eq.RegisterMouse()
 
-	res, err := resources()
-	if err != nil {
-		return err
-	}
-	defer res.Destroy()
-
 	fps := gut.NewFPS()
 	defer fps.Destroy()
 
 	game := &game{}
-	err = game.Init(disp, res, cons, fps)
+	err = game.Init(disp, settings, res, resFs, cons, fps)
 	if err != nil {
 		return err
 	}
@@ -94,6 +140,8 @@ func run() error {
 					log.Printf("Stopping game loop, user pressed Alt+F4")
 					return nil
 				}
+			case *allg5.DisplayResizeEvent:
+				game.ctx.DisplaySize = geom.Pt(disp.Width(), disp.Height())
 			}
 			game.Handle(e)
 			e = eq.Get()

cmd/krampus19/krampus19_console.go

@@ -0,0 +1,6 @@
+// +build windows,!console
+
+package main
+
+// #cgo LDFLAGS: -Wl,-subsystem,windows
+import "C"

cmd/krampus19/level.go

@@ -1,144 +0,0 @@
-package main
-
-import (
-	"errors"
-	"fmt"
-	"io"
-
-	"opslag.de/schobers/geom"
-)
-
-type entityType byte
-type tile byte
-
-const (
-	entityTypeInvalid   entityType = entityType(0)
-	entityTypeNone                 = '_'
-	entityTypeCharacter            = '@'
-	entityTypeVillain              = 'X'
-	entityTypeBrick                = 'B'
-	entityTypeCrate                = 'C'
-)
-
-func (e entityType) IsValid() bool {
-	switch e {
-	case entityTypeNone:
-	case entityTypeCharacter:
-	case entityTypeVillain:
-	case entityTypeBrick:
-	case entityTypeCrate:
-	default:
-		return false
-	}
-	return true
-}
-
-const (
-	tileInvalid tile = tile(0)
-	tileNothing      = '.'
-	tileBasic        = '#'
-	tileWater        = '~'
-)
-
-func (t tile) IsValid() bool {
-	switch t {
-	case tileNothing:
-	case tileBasic:
-	case tileWater:
-	default:
-		return false
-	}
-	return true
-}
-
-type level struct {
-	width    int
-	height   int
-	tiles    []tile
-	entities []entityType
-}
-
-func (l level) idxToPos(i int) geom.Point { return geom.Pt(i%l.width, i/l.width) }
-
-func (l level) posToIdx(p geom.Point) int {
-	if p.X < 0 || p.Y < 0 || p.X >= l.width || p.Y >= l.height {
-		return -1
-	}
-	return p.Y*l.width + p.X
-}
-
-func loadLevelAsset(r io.Reader) (level, error) {
-	var l level
-	ctx := levelContext{&l}
-	err := parseLines(r, ctx.parse)
-	if err != nil {
-		return level{}, err
-	}
-	return l, nil
-}
-
-type levelContext struct {
-	level *level
-}
-
-func (c *levelContext) parse(p *lineParser) parseLineFn {
-	if p.eof() {
-		return nil
-	}
-	switch p.peek() {
-	case "level:":
-		return c.parseContent
-	case "":
-		p.next() // skip
-		return c.parse
-	default:
-		return nil
-	}
-}
-
-func (c *levelContext) parseContent(p *lineParser) parseLineFn {
-	if p.next() != "level:" {
-		return p.emitErr(errors.New("expected level start"))
-	}
-	return c.parseRow
-}
-
-func (c *levelContext) parseRow(p *lineParser) parseLineFn {
-	if p.eof() {
-		return p.emitErr(errors.New("unexpected end of file"))
-	}
-	line := p.next()
-	if line == ":level" {
-		return c.parse
-	}
-	if c.level.height == 0 {
-		c.level.width = len(line) / 2
-	}
-	return c.addRow(p, line)
-}
-
-func (c *levelContext) addRow(p *lineParser, line string) parseLineFn {
-	var tiles []tile
-	var entities []entityType
-	for i := 0; i < len(line); i += 2 {
-		tiles = append(tiles, tile(line[i]))
-		entities = append(entities, entityType(line[i+1]))
-	}
-
-	for i, t := range tiles {
-		if !t.IsValid() {
-			return p.emitErr(fmt.Errorf("level contains invalid tile at (%d, %d)", i, c.level.height))
-		}
-	}
-	for i, e := range entities {
-		if !e.IsValid() {
-			return p.emitErr(fmt.Errorf("level contains invalid entity type at (%d, %d)", i, c.level.height))
-		}
-	}
-
-	c.level.height++
-	c.level.tiles = append(c.level.tiles, tiles...)
-	c.level.entities = append(c.level.entities, entities...)
-
-	return c.parseRow
-}

cmd/krampus19/levelpack.go

@@ -0,0 +1,129 @@
+package main
+
+import (
+	"errors"
+	"io"
+	"strings"
+
+	"opslag.de/schobers/krampus19/gut"
+
+	"opslag.de/schobers/krampus19/soko"
+)
+
+type levelPack struct {
+	name   string
+	order  []string
+	levels map[string]soko.Level
+}
+
+func (p levelPack) find(level string) int {
+	for i, l := range p.order {
+		if l == level {
+			return i
+		}
+	}
+	return -1
+}
+
+func (p levelPack) FindNext(level string) (string, bool) {
+	idx := p.find(level)
+	if idx == -1 || idx == len(p.order)-1 {
+		return "", false
+	}
+	return p.order[idx+1], true
+}
+
+func (p levelPack) Len() int { return len(p.order) }
+
+type parseLevelPackContext struct {
+	name   string
+	levels []string
+}
+
+func parseLevelPackAsset(r io.Reader, openLevelFn func(id string) (io.ReadCloser, error)) (levelPack, error) {
+	ctx := &parseLevelPackContext{}
+	err := gut.ParseLines(r, ctx.Parse)
+	if err != nil {
+		return levelPack{}, err
+	}
+
+	pack := levelPack{name: ctx.name, levels: map[string]soko.Level{}}
+	for _, id := range ctx.levels {
+		rc, err := openLevelFn(id)
+		if err != nil {
+			return levelPack{}, err
+		}
+		defer rc.Close()
+		level, err := soko.ParseLevel(rc)
+		if err != nil {
+			return levelPack{}, err
+		}
+		pack.order = append(pack.order, id)
+		pack.levels[id] = level
+	}
+
+	return pack, nil
+}
+
+func (c *parseLevelPackContext) Parse(p *gut.LineParser) gut.ParseLineFn {
+	if p.SkipSpaceEOF() {
+		return p.EmitErr(errors.New("empty level pack"))
+	}
+	return c.parse
+}
+
+func (c *parseLevelPackContext) parse(p *gut.LineParser) gut.ParseLineFn {
+	const levelsTag = "levels:"
+	const nameTag = "name:"
+
+	if p.SkipSpaceEOF() {
+		return nil
+	}
+
+	line := p.Next()
+	switch {
+	case strings.HasPrefix(line, nameTag):
+		c.name = strings.TrimSpace(line[len(nameTag):])
+		return c.parse
+	case strings.HasPrefix(line, levelsTag):
+		return gut.SkipSpaceBeforeContent(c.parseLevels)
+	}
+	return p.EmitErr(errors.New("tag not allowed"))
+}
+
+func (c *parseLevelPackContext) parseLevels(p *gut.LineParser) gut.ParseLineFn {
+	const levelTag = "level:"
+	const levelsEndTag = ":levels"
+
+	line := p.Next()
+	switch line {
+	case levelTag:
+		return gut.SkipSpaceBeforeContent(c.parseLevel)
+	case levelsEndTag:
+		return c.parse
+	}
+	return p.EmitErr(errors.New("tag not allowed"))
+}
+
+func (c *parseLevelPackContext) parseLevel(p *gut.LineParser) gut.ParseLineFn {
+	const idTag = "id:"
+
+	line := p.Next()
+	switch {
+	case strings.HasPrefix(line, idTag):
+		c.levels = append(c.levels, strings.TrimSpace(line[len(idTag):]))
+		return gut.SkipSpaceBeforeContent(c.parseLevelEnd)
+	}
+	return p.EmitErr(errors.New("must have an id tag"))
+}
+
+func (c *parseLevelPackContext) parseLevelEnd(p *gut.LineParser) gut.ParseLineFn {
+	const levelEndTag = ":level"
+
+	line := p.Next()
+	switch {
+	case strings.HasPrefix(line, levelEndTag):
+		return gut.SkipSpaceBeforeContent(c.parseLevels)
+	}
+	return p.EmitErr(errors.New("tag not allowed"))
+}

cmd/krampus19/levelpacks.go

@@ -0,0 +1,36 @@
+package main
+
+type levelPacks struct {
+	packs map[string]levelPack
+	order []string
+}
+
+func newLevelPacks() *levelPacks {
+	return &levelPacks{map[string]levelPack{}, nil}
+}
+
+func (p *levelPacks) Add(id string, pack levelPack) {
+	p.order = append(p.order, id)
+	p.packs[id] = pack
+}
+
+func (p *levelPacks) ByID(id string) levelPack { return p.packs[id] }
+
+func (p *levelPacks) FirstPackID() string {
+	if p.Len() == 0 {
+		return ""
+	}
+	return p.order[0]
+}
+
+func (p *levelPacks) Len() int { return len(p.order) }
+
+func (p *levelPacks) LenLevels() int {
+	var cnt int
+	for _, pack := range p.packs {
+		cnt += pack.Len()
+	}
+	return cnt
+}
+
+func (p *levelPacks) MustSelect() bool { return p.Len() != 1 }

cmd/krampus19/levelpackselect.go

@@ -0,0 +1,40 @@
+package main
+
+import (
+	"opslag.de/schobers/allg5"
+
+	"opslag.de/schobers/krampus19/alui"
+)
+
+type levelPackSelect struct {
+	alui.Menu
+
+	ctx *Context
+}
+
+func (s *levelPackSelect) Enter(ctx *Context) error {
+	s.ctx = ctx
+	s.Init()
+	s.AddChild(newHeader("Select a level pack"))
+	for _, id := range s.ctx.Levels.order {
+		var copy = id
+		s.Add(s.ctx.Levels.ByID(id).name, func() {
+			s.ctx.Navigation.SelectLevel(copy)
+		})
+	}
+	s.Add("Back to main menu", func() { s.ctx.Navigation.ShowMainMenu() })
+	return nil
+}
+
+func (s *levelPackSelect) Handle(e allg5.Event) {
+	switch e := e.(type) {
+	case *allg5.KeyDownEvent:
+		switch e.KeyCode {
+		case allg5.KeyEscape:
+			s.ctx.Navigation.ShowMainMenu()
+		}
+	}
+	s.Menu.Handle(e)
+}
+
+func (s *levelPackSelect) Leave() {}

cmd/krampus19/levelselect.go

@@ -0,0 +1,59 @@
+package main
+
+import (
+	"fmt"
+
+	"opslag.de/schobers/allg5"
+
+	"opslag.de/schobers/krampus19/alui"
+)
+
+type levelSelect struct {
+	alui.Menu
+
+	ctx *Context
+
+	packID string
+	pack   levelPack
+}
+
+func (s *levelSelect) Enter(ctx *Context) error {
+	s.ctx = ctx
+	s.pack = s.ctx.Levels.ByID(s.packID)
+	s.Init()
+	name := func(i int, steps int) string {
+		if steps == 0 {
+			return fmt.Sprintf("Level %d", i)
+		}
+		return fmt.Sprintf("Level %d (%d)", i, steps)
+	}
+	if s.ctx.Levels.MustSelect() {
+		s.AddChild(newHeader(fmt.Sprintf("Select a '%s' level", s.pack.name)))
+	} else {
+		s.AddChild(newHeader("Select a level"))
+	}
+	for i, id := range s.pack.order {
+		levelID := id
+		s.Add(name(i+1, s.ctx.Progress.Level(s.packID, levelID).Steps), func() {
+			s.ctx.Navigation.PlayLevel(s.packID, levelID)
+		})
+	}
+	if s.ctx.Levels.MustSelect() {
+		s.Add("Select level pack", func() { s.ctx.Navigation.SelectPack() })
+	}
+	s.Add("Back to main menu", func() { s.ctx.Navigation.ShowMainMenu() })
+	return nil
+}
+
+func (s *levelSelect) Handle(e allg5.Event) {
+	switch e := e.(type) {
+	case *allg5.KeyDownEvent:
+		switch e.KeyCode {
+		case allg5.KeyEscape:
+			s.ctx.Navigation.ShowMainMenu()
+		}
+	}
+	s.Menu.Handle(e)
+}
+
+func (s *levelSelect) Leave() {}

cmd/krampus19/lineparser.go

@@ -1,55 +0,0 @@
-package main
-
-import (
-	"errors"
-	"io"
-	"io/ioutil"
-	"strings"
-)
-
-type lineParser struct {
-	lines []string
-	i     int
-	err   error
-}
-
-var errUnexpectedEnd = errors.New("unexpected end of file")
-
-func (p *lineParser) eof() bool    { return p.i == len(p.lines) }
-func (p *lineParser) peek() string { return p.lines[p.i] }
-func (p *lineParser) next() string {
-	i := p.i
-	p.i++
-	return p.lines[i]
-}
-
-func (p *lineParser) emitErr(err error) parseLineFn {
-	p.err = err
-	return nil
-}
-
-func (p *lineParser) skipSpaceEOF() bool {
-	for !p.eof() && len(strings.TrimSpace(p.peek())) == 0 {
-		p.next()
-	}
-	return p.eof()
-}
-
-type parseLineFn func(p *lineParser) parseLineFn
-
-func parseLines(r io.Reader, fn parseLineFn) error {
-	content, err := ioutil.ReadAll(r)
-	if err != nil {
-		return err
-	}
-	lines := strings.Split(string(content), "\n")
-	for i, line := range lines {
-		lines[i] = strings.TrimRight(line, "\r\n")
-	}
-
-	parser := &lineParser{lines: lines}
-	for fn != nil {
-		fn = fn(parser)
-	}
-	return parser.err
-}

cmd/krampus19/mainmenu.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"opslag.de/schobers/allg5"
 	"opslag.de/schobers/krampus19/alui"
 )
 
@@ -10,11 +11,17 @@ type mainMenu struct {
 	ctx *Context
 }
 
+func newHeader(label string) alui.Control {
+	return alui.NewMargins(&alui.Label{ControlBase: alui.ControlBase{Font: "header"}, Text: label, TextAlign: allg5.AlignCenter}, 3*margin)
+}
+
 func (m *mainMenu) Enter(ctx *Context) error {
 	m.ctx = ctx
 	m.Init()
-	m.Add("Play", func() { m.ctx.Navigation.playLevel("1") })
-	m.Add("Quit", func() { m.ctx.Navigation.quit() })
+	m.AddChild(newHeader("Sokodragon"))
+	m.Add("Play", func() { m.ctx.Navigation.SelectPack() })
+	m.Add("Settings", func() { m.ctx.Navigation.ChangeSettings() })
+	m.Add("Quit", func() { m.ctx.Navigation.Quit() })
 	return nil
 }
 

cmd/krampus19/navigation.go

@@ -16,24 +16,42 @@ type scene interface {
 	Leave()
 }
 
-func (n *navigation) playLevel(l string) {
-	n.switchTo(&playLevel{name: l})
+func (n *navigation) ChangeSettings() {
+	n.switchTo(&changeSettings{})
 }
 
-func (n *navigation) quit() {
-	n.switchTo(nil)
+func (n *navigation) PlayLevel(packID, levelID string) {
+	n.switchTo(&playLevel{packID: packID, levelID: levelID})
 }
 
-func (n *navigation) showMainMenu() {
+func (n *navigation) SelectLevel(packID string) {
+	n.switchTo(&levelSelect{packID: packID})
+}
+
+func (n *navigation) SelectPack() {
+	if n.game.ctx.Levels.MustSelect() {
+		n.switchTo(&levelPackSelect{})
+	} else {
+		packID := n.game.ctx.Levels.FirstPackID()
+		n.SelectLevel(packID)
+	}
+}
+
+func (n *navigation) ShowMainMenu() {
 	n.switchTo(&mainMenu{})
 }
 
+func (n *navigation) Quit() {
+	n.switchTo(nil)
+}
+
 func (n *navigation) switchTo(s scene) {
 	if n.curr != nil {
 		n.curr.Leave()
 	}
 	n.curr = s
 	n.game.scene.Proxy = s
+	n.game.scene.Visible = s != nil
 	if n.curr != nil {
 		n.curr.Enter(n.game.ctx)
 	}

cmd/krampus19/playlevel.go

@@ -3,374 +3,254 @@ package main
 import (
 	"fmt"
 	"log"
-	"sort"
-	"time"
+	"strconv"
 
 	"opslag.de/schobers/allg5"
 	"opslag.de/schobers/geom"
 	"opslag.de/schobers/krampus19/alui"
-	"opslag.de/schobers/krampus19/gut"
+	"opslag.de/schobers/krampus19/soko"
 )
 
 type playLevel struct {
 	alui.ControlBase
 
-	ctx *Context
+	ctx  *Context
+	init bool
 
 	menu     *alui.Menu
+	end      alui.Control
 	showMenu bool
 
-	name     string
-	offset   geom.PointF32
-	scale    float32
-	keysDown keyPressedState
+	packID  string
+	levelID string
+	offset  geom.PointF32
+	scale   float32
 
-	level   level
-	player  *entity
-	villain *entity
-	bricks  []*entity
-	sunken  []*entity
-	steps   int
-	tick    time.Duration
-	ani     gut.Animations
+	state       playLevelState
+	pathFinding bool
 }
 
 type keyPressedState map[allg5.Key]bool
 
-func (s keyPressedState) CountPressed(keys ...allg5.Key) int {
-	var cnt int
+func (s keyPressedState) ArePressed(keys ...allg5.Key) []allg5.Key {
+	pressed := make([]allg5.Key, 0, len(keys))
 	for _, k := range keys {
 		if s[k] {
-			cnt++
+			pressed = append(pressed, k)
 		}
 	}
-	return cnt
+	return pressed
 }
 
-type entity struct {
-	typ entityType
-	pos geom.Point
-	scr geom.PointF32
-}
-
-func newEntity(typ entityType, pos geom.Point) *entity {
-	return &entity{typ, pos, pos.ToF32()}
-}
-
-type posToScrFn func(geom.Point) geom.PointF32
-
-type entityMoveAnimation struct {
-	e        *entity
-	from, to geom.Point
-	pos      geom.PointF32
-}
-
-func newEntityMoveAnimation(e *entity, to geom.Point) *entityMoveAnimation {
-	ani := &entityMoveAnimation{e: e, from: e.pos, to: to, pos: e.pos.ToF32()}
-	ani.e.pos = to
-	return ani
-}
-
-func (a *entityMoveAnimation) Animate(start, now time.Duration) bool {
-	const duration = 240 * time.Millisecond
-
-	progress := float32((now-start)*1000/duration) * .001
-	from, to := a.from.ToF32(), a.to.ToF32()
-	if progress >= 1 {
-		a.e.scr = to
-		return false
-	}
-	a.e.scr = to.Sub(from).Mul(progress).Add(from)
-	return true
-}
-
-func (l *playLevel) idxToPos(i int) geom.PointF32 { return l.level.idxToPos(i).ToF32() }
-
-func (l *playLevel) isIdle() bool { return l.ani.Idle() }
-
-func findEntityAt(entities []*entity, pos geom.Point) *entity {
-	idx := findEntityIdx(entities, pos)
-	if idx == -1 {
-		return nil
-	}
-	return entities[idx]
-}
-
-func findEntityIdx(entities []*entity, pos geom.Point) int {
-	for i, e := range entities {
-		if e.pos == pos {
-			return i
-		}
-	}
-	return -1
-}
-
-func (l *playLevel) findEntityAt(pos geom.Point) *entity {
-	if l.player.pos == pos {
-		return l.player
-	}
-	brick := findEntityAt(l.bricks, pos)
-	if brick != nil {
-		return brick
-	}
-	return findEntityAt(l.sunken, pos)
-}
-
-func (l *playLevel) checkTile(pos geom.Point, check func(pos geom.Point, idx int, t tile) bool) bool {
-	return l.checkTileNotFound(pos, check, false)
-}
-
-func (l *playLevel) checkTileNotFound(pos geom.Point, check func(pos geom.Point, idx int, t tile) bool, notFound bool) bool {
-	idx := l.level.posToIdx(pos)
-	if idx == -1 {
-		return notFound
-	}
-	return check(pos, idx, l.level.tiles[idx])
-}
-
-func (l *playLevel) isSolidTile(pos geom.Point, idx int, t tile) bool {
-	switch t {
-	case tileBasic:
-		return true
-	case tileWater:
-		return findEntityAt(l.sunken, pos) != nil
-	}
-	return false
-}
-
-func (l *playLevel) wouldBrickSink(pos geom.Point, idx int, t tile) bool {
-	return t == tileWater && findEntityAt(l.sunken, pos) == nil
-}
-
-func (l *playLevel) isObstructed(pos geom.Point, idx int, t tile) bool {
-	if findEntityAt(l.bricks, pos) != nil {
-		return true // brick
-	}
-	switch l.level.tiles[idx] {
-	case tileWater:
-		return false
-	case tileBasic:
-		return false
-	}
-	return true
-}
-
-func (l *playLevel) canMove(from, dir geom.Point) bool {
-	to := from.Add(dir)
-	if !l.checkTile(to, l.isSolidTile) {
-		return false
-	}
-	brick := findEntityAt(l.bricks, to)
-	if brick != nil {
-		brickTo := to.Add(dir)
-		return !l.checkTileNotFound(brickTo, l.isObstructed, true)
-	}
-	return true
-}
+func (s keyPressedState) CountPressed(keys ...allg5.Key) int { return len(s.ArePressed(keys...)) }
 
 func (l *playLevel) Enter(ctx *Context) error {
 	l.ctx = ctx
 
 	l.menu = alui.NewMenu()
 	l.menu.Add("Resume", func() { l.showMenu = false })
-	l.menu.Add("Quit to main menu", func() { l.ctx.Navigation.showMainMenu() })
-	l.menu.Add("Quit to desktop", func() { l.ctx.Navigation.quit() })
+	l.menu.Add("Restart", func() { l.ctx.Navigation.PlayLevel(l.packID, l.levelID) })
+	l.menu.Add("Select other level", func() { l.ctx.Navigation.SelectLevel(l.packID) })
+	l.menu.Add("Quit to main menu", func() { l.ctx.Navigation.ShowMainMenu() })
+	l.menu.Add("Quit to desktop", func() { l.ctx.Navigation.Quit() })
+	l.menu.OnEscape = func() { l.showMenu = false }
 
-	l.keysDown = keyPressedState{}
-	l.level = l.ctx.Levels[l.name]
-	l.bricks = nil
-	l.sunken = nil
-	for i, e := range l.level.entities {
-		switch e {
-		case entityTypeBrick:
-			l.bricks = append(l.bricks, newEntity(e, l.level.idxToPos(i)))
-		case entityTypeCharacter:
-			l.player = newEntity(e, l.level.idxToPos(i))
-		case entityTypeVillain:
-			l.villain = newEntity(e, l.level.idxToPos(i))
-		}
-	}
+	l.init = true
+	l.state.Init(l.ctx, l.packID, l.levelID, l.onComplete)
 	return nil
 }
 
 func (l *playLevel) Leave() {}
 
-func (l *playLevel) posToScreen(p geom.Point) geom.PointF32 {
-	return l.posToScreenF32(p.ToF32())
+func (l *playLevel) onComplete() {
+	menu := alui.NewMenu()
+	menu.AddChild(alui.NewMargins(&alui.Label{ControlBase: alui.ControlBase{Font: "header"}, Text: "Congratulations", TextAlign: allg5.AlignCenter}, 3*margin, 0, 2*margin))
+	menu.AddChild(alui.NewMargins(&alui.Label{Text: fmt.Sprintf("You've completed the level in %d steps.", l.state.steps), TextAlign: allg5.AlignCenter}, 0, 0, 2*margin))
+
+	progress := l.ctx.Progress.Level(l.packID, l.levelID)
+	if l.state.steps < progress.Steps || progress.Steps == 0 {
+		var improvement = progress.Steps - l.state.steps
+		if improvement > 0 { // first time it is lower than zero (no previous record).
+			menu.AddChild(alui.NewMargins(&alui.Label{Text: fmt.Sprintf("This is an improvement of %d steps.", improvement), TextAlign: allg5.AlignCenter}, 0, 0, 2*margin))
+		}
+
+		err := l.ctx.Progress.Update(l.packID, l.levelID, func(p *levelProgress) {
+			p.Steps = l.state.steps
+		})
+		if err != nil {
+			log.Printf("Unable to store progress; err: %v", err)
+		}
+	}
+
+	nextID, ok := l.state.pack.FindNext(l.levelID)
+	if ok {
+		menu.Add("Continue with next", func() { l.ctx.Navigation.PlayLevel(l.packID, nextID) })
+	}
+	if l.ctx.Levels.MustSelect() {
+		menu.Add("Select level pack", func() { l.ctx.Navigation.SelectPack() })
+	}
+	menu.Add("Select level", func() { l.ctx.Navigation.SelectLevel(l.packID) })
+	menu.Add("Go to main menu", func() { l.ctx.Navigation.ShowMainMenu() })
+
+	l.end = menu
 }
 
-func (l *playLevel) posToScreenF32(p geom.PointF32) geom.PointF32 {
-	pos := p.Add2D(.5, .5)
-	pos = geom.PtF32(pos.X*148-pos.Y*46, pos.Y*82)
-	pos = geom.PtF32(pos.X*l.scale, pos.Y*l.scale)
-	return pos.Add(l.offset)
+func (l *playLevel) posToScreenF32(p geom.PointF32, z float32) geom.PointF32 {
+	pos := l.posToCabinet(p.Add2D(.5, .5)).Add2D(0, z)
+	return pos.Mul(l.scale).Add(l.offset)
 }
 
-// <-  168->
-//   <-128->
+func (l *playLevel) posToCabinet(p geom.PointF32) geom.PointF32 {
+	return geom.PtF32(p.X*100-p.Y*50, p.Y*70)
+}
+
+// <-  150->
+//   <-100->
 //
 //   /----/|   ^  ^
-//  /    / /   |  72
-// /----/ /    92 v  ^
-// |----|/     v     v 20
+//  /    / |   |  70
+// /----/  |  170 v  ^
+// |    |  |   |     |
+// |    | /    |    100
+// |----|/     v     v
 //
-// Gap: 20
-// Center: 84,46
-// Offset between horizontal tiles: 148,0
-// Offset between vertical tiles: -46,82
+// Offset between horizontal tiles: 100,0
+// Offset between vertical tiles: -25,70
 
 func (l *playLevel) Layout(ctx *alui.Context, bounds geom.RectangleF32) {
-	l.scale = bounds.Dy() / 1080
+	if l.init {
+		l.scale = 1
+		l.offset = geom.PointF32{}
 
-	tilesCenter := geom.PtF32(.5*float32(l.level.width), .5*float32(l.level.height))
-	tilesCenter = geom.PtF32(tilesCenter.X*148-tilesCenter.Y*46, tilesCenter.Y*82)
-	tilesCenter = geom.PtF32(tilesCenter.X*l.scale, tilesCenter.Y*l.scale)
-	center := bounds.Center()
-	l.offset = geom.PtF32(center.X-tilesCenter.X, center.Y-tilesCenter.Y)
-
-	l.ani.Animate(l.ctx.Tick)
-}
-
-func (l *playLevel) tryPlayerMove(dir geom.Point, key allg5.Key) {
-	if !l.isIdle() {
-		return
-	}
-
-	to := l.player.pos.Add(dir)
-	if !l.canMove(l.player.pos, dir) {
-		log.Printf("Move is not allowed (tried out move to %s after key '%s' was pressed)", to, gut.KeyToString(key))
-		return
-	}
-
-	l.steps++
-	log.Printf("Moving player to %s", to)
-	l.ani.StartFn(l.ctx.Tick, newEntityMoveAnimation(l.player, to), func() {
-		log.Printf("Player movement finished")
-		if l.keysDown[key] && l.keysDown.CountPressed(l.ctx.Settings.Controls.MovementKeys()...) == 1 {
-			log.Printf("Key %s is still down, moving further", gut.KeyToString(key))
-			l.tryPlayerMove(dir, key)
-		}
-	})
-
-	if brick := findEntityAt(l.bricks, to); brick != nil {
-		log.Printf("Pushing brick at %s", to)
-		brickTo := to.Add(dir)
-		l.ani.StartFn(l.ctx.Tick, newEntityMoveAnimation(brick, brickTo), func() {
-			log.Printf("Brick movement finished")
-			if l.checkTile(brickTo, l.wouldBrickSink) {
-				log.Printf("Sinking brick at %s", brickTo)
-				idx := findEntityIdx(l.bricks, brickTo)
-				l.bricks = append(l.bricks[:idx], l.bricks[idx+1:]...)
-				l.sunken = append(l.sunken, brick)
+		level := l.state.Level()
+		var contentCenter = l.posToScreenF32(geom.PtF32(.5*float32(level.Width), .5*float32(level.Height)), 0)
+		var content = geom.RectF32(contentCenter.X, contentCenter.Y, contentCenter.X, contentCenter.Y)
+		for idx, tile := range l.state.Level().Tiles {
+			if tile == soko.TileTypeNothing || tile == soko.TileTypeInvalid {
+				continue
 			}
-		})
+			pos := level.IdxToPos(idx).ToF32()
+			bottomLeft := l.posToScreenF32(pos.Add2D(-1.5, 1.5), 100)
+			content.Min = geom.MinPtF32(content.Min, bottomLeft)
+			content.Max = geom.MaxPtF32(content.Max, bottomLeft)
+			topRight := l.posToScreenF32(pos.Add2D(1.5, -1.5), 0)
+			content.Min = geom.MinPtF32(content.Min, topRight)
+			content.Max = geom.MaxPtF32(content.Max, topRight)
+		}
+		l.scale = geom.Min32(bounds.Dx()/content.Dx(), bounds.Dy()/content.Dy())
+
+		contentCenter = content.Center().Mul(l.scale)
+		center := bounds.Center()
+		l.offset = geom.PtF32(center.X-contentCenter.X, center.Y-contentCenter.Y)
+		l.init = false
 	}
+
+	l.state.Tick(l.ctx.Tick)
 }
 
 func (l *playLevel) Handle(e allg5.Event) {
 	switch e := e.(type) {
 	case *allg5.KeyDownEvent:
-		l.keysDown[e.KeyCode] = true
+		l.state.PressKey(e.KeyCode)
 	case *allg5.KeyUpEvent:
-		l.keysDown[e.KeyCode] = false
+		l.state.ReleaseKey(e.KeyCode)
 	}
 
-	if l.showMenu {
+	switch {
+	case l.showMenu:
 		l.menu.Handle(e)
+	case l.state.complete:
+		l.end.Handle(e)
+	default:
 		switch e := e.(type) {
 		case *allg5.KeyDownEvent:
 			switch e.KeyCode {
 			case allg5.KeyEscape:
-				l.showMenu = false
+				l.showMenu = true
+				l.menu.Activate(0)
+			case allg5.KeyF5:
+				l.pathFinding = !l.pathFinding
 			}
-		}
-		return
-	}
-
-	switch e := e.(type) {
-	case *allg5.KeyDownEvent:
-		switch e.KeyCode {
-		case allg5.KeyEscape:
-			l.showMenu = true
-			l.menu.Activate(0)
-		case l.ctx.Settings.Controls.MoveUp:
-			l.tryPlayerMove(geom.Pt(0, -1), e.KeyCode)
-		case l.ctx.Settings.Controls.MoveRight:
-			l.tryPlayerMove(geom.Pt(1, 0), e.KeyCode)
-		case l.ctx.Settings.Controls.MoveDown:
-			l.tryPlayerMove(geom.Pt(0, 1), e.KeyCode)
-		case l.ctx.Settings.Controls.MoveLeft:
-			l.tryPlayerMove(geom.Pt(-1, 0), e.KeyCode)
+			l.state.TryPlayerMove(e.KeyCode)
 		}
 	}
 }
 
-func (l *playLevel) Render(ctx *alui.Context, bounds geom.RectangleF32) {
-	basicTile := l.ctx.Textures["basic_tile"]
-	waterTile := l.ctx.Textures["water_tile"]
-	sunkenBrickTile := l.ctx.Textures["sunken_brick_tile"]
+func (l *playLevel) drawSprite(name, partName string, pos entityLoc) {
+	l.ctx.SpriteDrawer.Draw(name, partName, l.posToScreenF32(pos.pos, pos.z), DrawSpriteOptions{Scale: l.scale})
+}
 
-	opts := allg5.DrawOptions{Center: true, Scale: allg5.NewUniformScale(l.scale * (168 / float32(basicTile.Width())))}
-	level := l.level
-	for i, t := range level.tiles {
-		pos := geom.Pt(i%level.width, i/level.width)
-		scrPos := l.posToScreen(pos)
+func (l *playLevel) drawSpriteAlpha(name, partName string, pos entityLoc, alpha float32) {
+	a := byte(alpha * 255)
+	c := allg5.NewColorAlpha(a, a, a, a)
+	l.ctx.SpriteDrawer.Draw(name, partName, l.posToScreenF32(pos.pos, pos.z), DrawSpriteOptions{Scale: l.scale, Tint: &c})
+}
+
+func (l *playLevel) Render(ctx *alui.Context, bounds geom.RectangleF32) {
+	level := l.state.level
+
+	drawParticles := func(particles []particle) {
+		for _, p := range particles {
+			l.drawSpriteAlpha("particles", "splash", entityLoc{p.pos, p.z}, p.opaq)
+		}
+	}
+
+	for i, t := range level.Tiles {
+		pos := geom.Pt(i%level.Width, i/level.Width)
+		scr := entityLoc{pos.ToF32(), 0}
 		switch t {
-		case tileBasic:
-			basicTile.DrawOptions(scrPos.X, scrPos.Y, opts)
-		case tileWater:
-			scrPos := l.posToScreenF32(pos.ToF32().Add2D(0, .2*l.scale))
-			if findEntityAt(l.sunken, pos) == nil {
-				waterTile.DrawOptions(scrPos.X, scrPos.Y, opts)
+		case soko.TileTypeBasic:
+			if l.state.IsNextToMagma(pos) {
+				l.drawSprite("lava_brick", "magma", scr)
 			} else {
-				sunkenBrickTile.DrawOptions(scrPos.X, scrPos.Y, opts)
+				l.drawSprite("lava_brick", "lava_brick", scr)
+			}
+		case soko.TileTypeMagma:
+			l.drawSprite("magma", "magma", scr)
+			brick := l.state.FindSunkenBrickEntity(pos)
+			if brick != nil {
+				behind, front := splitParticles(scr.pos.Y, l.state.Particles(pos))
+				drawParticles(behind)
+				l.drawSprite("brick", "brick", brick.scr)
+				l.drawSprite("magma", "sunken_overlay", scr)
+				drawParticles(front)
 			}
 		}
 	}
 
-	character := l.ctx.Textures["main_character"]
-	villain := l.ctx.Textures["villain_character"]
-	brick := l.ctx.Textures["brick"]
-	crate := l.ctx.Textures["crate"]
-
-	var entities []*entity
-	entities = append(entities, l.player)
-	entities = append(entities, l.villain)
-	entities = append(entities, l.bricks...)
-
-	sort.Slice(entities, func(i, j int) bool {
-		if entities[i].scr.Y == entities[j].scr.Y {
-			return entities[i].scr.X < entities[j].scr.X
-		}
-		return entities[i].scr.Y < entities[j].scr.Y
-	})
-
+	entities := l.state.Entities().RenderOrder()
 	for _, e := range entities {
-		scrPos := l.posToScreenF32(e.scr)
 		switch e.typ {
-		case entityTypeCharacter:
-			scrPos := l.posToScreenF32(e.scr.Add2D(-.2*l.scale, -.9*l.scale))
-			character.DrawOptions(scrPos.X, scrPos.Y, opts)
-		case entityTypeVillain:
-			scrPos := l.posToScreenF32(e.scr.Add2D(-.2*l.scale, -.9*l.scale))
-			villain.DrawOptions(scrPos.X, scrPos.Y, opts)
-		case entityTypeBrick:
-			if findEntityAt(l.bricks, e.pos) == nil {
-				break
-			}
-			scrPos := l.posToScreenF32(e.scr.Add2D(-.2*l.scale, -.7*l.scale))
-			brick.DrawOptions(scrPos.X, scrPos.Y, opts)
-		case entityTypeCrate:
-			crate.DrawOptions(scrPos.X, scrPos.Y, opts)
+		case soko.EntityTypeBrick:
+			l.drawSprite("brick", "brick", e.scr)
+		case soko.EntityTypePlayer:
+			l.drawSprite("dragon", "dragon", e.scr)
+		case soko.EntityTypeTarget:
+			l.drawSprite("egg", "egg", e.scr)
 		}
 	}
 
 	font := ctx.Fonts.Get("default")
-	steps := fmt.Sprintf("STEPS: %d", l.steps)
+
+	if l.pathFinding {
+		dists := soko.NewPathFinder(&l.state.state).FindDistances()
+		for i := range level.Tiles {
+			pos := geom.Pt(i%level.Width, i/level.Width)
+			scr := entityLoc{pos.ToF32(), 0}
+			posDist := l.posToScreenF32(scr.pos, -20)
+			ctx.Fonts.DrawAlignFont(font, posDist.X, posDist.Y, posDist.X, ctx.Palette.Text, allg5.AlignCenter, strconv.Itoa(dists[i]))
+		}
+	}
+
+	steps := fmt.Sprintf("STEPS: %d", l.state.Steps())
 	ctx.Fonts.DrawAlignFont(font, bounds.Min.X, 24, bounds.Max.X, ctx.Palette.Text, allg5.AlignCenter, steps)
 
-	if l.showMenu {
+	switch {
+	case l.showMenu:
 		allg5.DrawFilledRectangle(bounds.Min.X, bounds.Min.Y, bounds.Max.X, bounds.Max.Y, allg5.NewColorAlpha(0, 0, 0, 0xaf))
 		l.menu.Render(ctx, bounds)
+	case l.state.complete:
+		allg5.DrawFilledRectangle(bounds.Min.X, bounds.Min.Y, bounds.Max.X, bounds.Max.Y, allg5.NewColorAlpha(0, 0, 0, 0xaf))
+		l.end.Render(ctx, bounds)
 	}
 }

cmd/krampus19/playlevelstate.go

@@ -0,0 +1,188 @@
+package main
+
+import (
+	"log"
+	"time"
+
+	"opslag.de/schobers/allg5"
+	"opslag.de/schobers/geom"
+	"opslag.de/schobers/krampus19/gut"
+	"opslag.de/schobers/krampus19/soko"
+)
+
+type playLevelState struct {
+	ctx *Context
+
+	pack   levelPack
+	level  soko.Level
+	state  soko.State
+	player *entity
+	egg    *entity
+	bricks entityMap
+	sunken entityMap
+	splash map[geom.Point]*splashAnimation
+
+	steps      int
+	complete   bool
+	onComplete func()
+
+	tick     time.Duration
+	ani      gut.Animations
+	keysDown keyPressedState
+}
+
+func (s *playLevelState) Entities() entityMap {
+	entities := entityMap{}
+	entities[s.player.id] = s.player
+	entities[s.egg.id] = s.egg
+	for id, e := range s.bricks {
+		entities[id] = e
+	}
+	return entities
+}
+
+func (s *playLevelState) Particles(at geom.Point) []particle {
+	var particles []particle
+	for pos, ani := range s.splash {
+		if pos != at {
+			continue
+		}
+		log.Println("Found particles at", at)
+		for _, p := range ani.particles {
+			particles = append(particles, p.part)
+		}
+	}
+	return particles
+}
+
+func (s *playLevelState) FindSunkenBrickEntity(pos geom.Point) *entity {
+	idx := s.level.PosToIdx(pos)
+	if idx == -1 {
+		return nil
+	}
+	id := s.state.SunkenBricks[idx]
+	if id != -1 {
+		return s.sunken[id]
+	}
+	return nil
+}
+
+func (s *playLevelState) IsNextToMagma(pos geom.Point) bool {
+	return s.state.Any(soko.IsMagma, soko.Neighbours(pos)...)
+}
+
+func (s *playLevelState) Init(ctx *Context, pack, level string, onComplete func()) {
+	s.ctx = ctx
+	s.pack = ctx.Levels.ByID(pack)
+	s.level = s.pack.levels[level]
+	s.state = s.level.State()
+	s.bricks = nil
+	s.sunken = nil
+	s.splash = map[geom.Point]*splashAnimation{}
+
+	newEntity := func(e soko.Entity) *entity { return newEntity(e, s.state.IdxToPos[e.Pos]) }
+
+	s.player = newEntity(s.state.Player)
+	s.egg = newEntity(s.state.Target)
+	s.bricks = entityMap{}
+	for _, e := range s.state.Entities {
+		if e.Typ != soko.EntityTypeBrick {
+			continue
+		}
+		s.bricks[e.ID] = newEntity(soko.Entity{ID: e.ID, Pos: e.Pos, Typ: soko.EntityTypeBrick})
+	}
+	s.sunken = entityMap{}
+	s.keysDown = keyPressedState{}
+	s.onComplete = onComplete
+}
+
+func (s *playLevelState) Level() soko.Level { return s.level }
+
+func (s *playLevelState) PressKey(key allg5.Key) {
+	s.keysDown[key] = true
+}
+
+func (s *playLevelState) ReleaseKey(key allg5.Key) {
+	s.keysDown[key] = false
+}
+
+func (s *playLevelState) Steps() int { return s.steps }
+
+func (s *playLevelState) Tick(now time.Duration) {
+	s.ani.Animate(now)
+}
+
+func (s *playLevelState) TryPlayerMove(key allg5.Key) {
+	var dir soko.Direction
+	switch key {
+	case s.ctx.Settings.Controls.MoveUp:
+		dir = soko.DirectionUp
+	case s.ctx.Settings.Controls.MoveRight:
+		dir = soko.DirectionRight
+	case s.ctx.Settings.Controls.MoveDown:
+		dir = soko.DirectionDown
+	case s.ctx.Settings.Controls.MoveLeft:
+		dir = soko.DirectionLeft
+	default:
+		return
+	}
+	s.tryPlayerMove(dir)
+}
+
+func (s *playLevelState) tryPlayerMove(dir soko.Direction) {
+	playerPt := s.state.IdxToPos[s.state.Player.Pos]
+	if s.player.scr.pos != playerPt.ToF32() {
+		return
+	}
+
+	state, ok := s.state.MovePlayer(dir)
+	if !ok {
+		log.Printf("Move is not allowed (tried out move %s)", dir.String())
+		return
+	}
+
+	to := state.Player.Pos
+	toPt := state.IdxToPos[to]
+
+	if brickID := s.state.Bricks[to]; brickID != -1 {
+		log.Printf("Brick %d moved", brickID)
+		brick := s.bricks[brickID]
+		brickTo := state.Entities.ByID(brickID).Pos
+		brickToPt := state.IdxToPos[brickTo]
+		s.ani.StartFn(s.ctx.Tick, newMoveAnimation(brick, toPt, brickToPt), func() {
+			log.Printf("Brick movement finished")
+			if sunkenBrickID := state.SunkenBricks[brickTo]; sunkenBrickID == brickID {
+				log.Printf("Sinking brick %d", brickID)
+				delete(s.bricks, brickID)
+				s.sunken[brickID] = brick
+				s.ani.Start(s.ctx.Tick, newSinkAnimation(brick))
+
+				splash := newSplashAnimation(brickToPt)
+				s.splash[brickToPt] = splash
+				s.ani.StartFn(s.ctx.Tick, splash, func() {
+					delete(s.splash, brickToPt)
+				})
+			}
+		})
+	}
+
+	s.steps++
+	log.Printf("Moving player to %s", toPt)
+	s.ani.StartFn(s.ctx.Tick, newMoveAnimation(s.player, playerPt, toPt), func() {
+		log.Printf("Player movement finished")
+		if to == state.Target.Pos {
+			s.complete = true
+			if onComplete := s.onComplete; onComplete != nil {
+				onComplete()
+			}
+		} else {
+			pressed := s.keysDown.ArePressed(s.ctx.Settings.Controls.MovementKeys()...)
+			if len(pressed) == 1 {
+				key := pressed[0]
+				log.Printf("Movement key %s is down, moving further", gut.KeyToString(key))
+				s.TryPlayerMove(key)
+			}
+		}
+	})
+	s.state = state
+}

cmd/krampus19/progress.go

@@ -0,0 +1,67 @@
+package main
+
+type progress struct {
+	Packs map[string]packProgress
+}
+
+func (p *progress) Pack(packID string) packProgress {
+	if p.Packs == nil {
+		p.Packs = map[string]packProgress{}
+	}
+	return p.Packs[packID]
+}
+
+func (p *progress) Level(packID, levelID string) levelProgress {
+	pack := p.Pack(packID)
+	return pack.Level(levelID)
+}
+
+func (p *progress) Update(packID, levelID string, update func(*levelProgress)) error {
+	pack := p.Pack(packID)
+	pack.Update(levelID, update)
+	p.Packs[packID] = pack
+	return p.store()
+}
+
+type packProgress struct {
+	Levels map[string]levelProgress
+}
+
+func (p *packProgress) Level(id string) levelProgress {
+	if p.Levels == nil {
+		p.Levels = map[string]levelProgress{}
+	}
+	return p.Levels[id]
+}
+
+func (p *packProgress) Update(id string, update func(*levelProgress)) {
+	level := p.Level(id)
+	update(&level)
+	p.Levels[id] = level
+}
+
+type levelProgress struct {
+	Steps int
+}
+
+func (p *progress) store() error {
+	path, err := userFile("progress.json")
+	if err != nil {
+		return err
+	}
+	return encodeJSON(path, p)
+}
+
+func (p *progress) load() error {
+	path, err := userFile("progress.json")
+	if err != nil {
+		return err
+	}
+	var fromFile progress
+	err = decodeJSON(path, &fromFile)
+	if err != nil {
+		return err
+	}
+	*p = fromFile
+	return nil
+}

cmd/krampus19/res/levels/empty.txt

@@ -0,0 +1,11 @@
+level:
+._._._._._._._._._._
+._._._._._._._._._._
+._._._._._._._._._._
+._._._._._._._._._._
+._._._._._._._._._._
+._._._._._._._._._._
+._._._._._._._._._._
+._._._._._._._._._._
+._._._._._._._._._._
+:level

cmd/krampus19/res/levels/level1.txt

@@ -1,11 +0,0 @@
-level:
-._._._._._._._._._._
-._._#_#_#_._._._._._
-._._#_._#B._._._._._
-._._#_#_#_._._._._._
-._._#_._#B._._._._._
-._#@#_#_#_~_~_#_#X._
-._._._._~_~_#_._._._
-._._._._#_#_#_._._._
-._._._._._._._._._._
-:level

cmd/krampus19/res/levels/pack1/info.txt

@@ -0,0 +1,21 @@
+name: Standard
+
+levels:
+
+level:
+id: 1
+:level
+
+level:
+id: 3
+:level
+
+level:
+id: 2
+:level
+
+level:
+id: 4
+:level
+
+:levels

cmd/krampus19/res/levels/pack1/level1.txt

@@ -0,0 +1,11 @@
+level:
+._._._._._._._._._._
+._#_#_#_#_~_~_~_#_._
+._#_#_._#B~_~_#_#_._
+._#_#_#_#_~_~_~_#_._
+._#_#_._#B~_~_#_#_._
+._#@#_#_#_~_~_#_#X._
+._#_#_~_~_~_#_#_#_._
+._#_#_~_~_~_#_#_#_._
+._._._._._._._._._._
+:level

cmd/krampus19/res/levels/pack1/level2.txt

@@ -0,0 +1,13 @@
+level:
+._._._._._._._._._._._._._._._._._._._._
+._._._._._#_#_#_._._._._._._._._._._._._
+._._._._._#B#_#_._._._._._._._._._._._._
+._._._._._#_#_#B._._._._._._._._._._._._
+._._._#_#_#B#_#B#_._._._._._._._._._._._
+._._._#_._#_._._#_._._._._#X#_~_~_~_#_._
+._#_#_#_._#_._._#_._._._._._._._~_~_#_._
+._#_#B#_#_#B#_#_#_#_#_#_#_#_#_#_~_#_#_._
+._._._._._#_._._._#_._#@._._._._#_#_._._
+._._._._._#_#_#_#_#_._._._._._._._._._._
+._._._._._._._._._._._._._._._._._._._._
+:level

cmd/krampus19/res/levels/pack1/level3.txt

@@ -0,0 +1,11 @@
+level:
+._._._._._._._._._._
+._._._._._._._._._._
+._~_#_#_#_#B#_._._._
+._~_#B#_#_._#_._._._
+._~_._#_~_#_#_._._._
+._#X._#_~_#_._._._._
+._._#_#B#_#_._._._._
+._._#@#_._._._._._._
+._._._._._._._._._._
+:level

cmd/krampus19/res/levels/pack1/level4.txt

@@ -0,0 +1,16 @@
+level:
+._._._._._._._._._._._._
+._._#_#_._._._._._._._._
+._._#_#B#_#B#@#_#_._._._
+._._#_#_#_#_#B#_#_._._._
+._._._._._._#_._._._._._
+._._._._._._#_._._._._._
+._._._._._._#B._._._._._
+._._._#_#_._#_._#_#_._._
+._#_#_#_#_~_#_#_#_#_#_._
+._#_._._#_._#_._#_._#_._
+._#_._#X~_._~_._~_._#_._
+._#_._._#_._#_._#_._#_._
+._#_#_#_#_#_~_#_#_#_#_._
+._._._._._._._._._._._._
+:level

cmd/krampus19/res/sprites/brick.txt

@@ -0,0 +1,11 @@
+sprite:
+texture: brick
+
+part:
+name: brick
+sub_texture: 0,0,1020,1140
+anchor: 510,870
+scale: 6
+:part
+
+:sprite

cmd/krampus19/res/sprites/dragon.txt

@@ -2,27 +2,10 @@ sprite:
 texture: dragon
 
 part:
-name: body
-sub_texture: 0,0,2107,1284
-anchor: 1065,594
-:part
-
-part:
-name: foot
-sub_texture: 42,1345,529,856
-anchor: 386,1283
-:part
-
-part:
-name: upper_wing
-sub_texture: 2112,39,1080,651
-anchor: 2413,644
-:part
-
-part:
-name: lower_wing
-sub_texture: 2170,764,1030,736
-anchor: 2658,799
+name: dragon
+sub_texture: 0,0,1140,1980
+anchor: 570,1920
+scale: 5
 :part
 
 :sprite

cmd/krampus19/res/sprites/egg.txt

@@ -0,0 +1,11 @@
+sprite:
+texture: egg
+
+part:
+name: egg
+sub_texture: 0,0,1140,1980
+anchor: 570,1860
+scale: 6
+:part
+
+:sprite

cmd/krampus19/res/sprites/lava_brick.txt

@@ -0,0 +1,18 @@
+sprite:
+texture: lava_brick
+
+part:
+name: lava_brick
+sub_texture: 0,0,1020,1140
+anchor: 510,270
+scale: 6
+:part
+
+part:
+name: magma
+sub_texture: 0,1140,1020,1140
+anchor: 510,1410
+scale: 6
+:part
+
+:sprite

cmd/krampus19/res/sprites/magma.txt

@@ -0,0 +1,18 @@
+sprite:
+texture: magma
+
+part:
+name: magma
+sub_texture: 0,0,1020,1140
+anchor: 510,270
+scale: 6
+:part
+
+part:
+name: sunken_overlay
+sub_texture: 0,1140,1020,1140
+anchor: 510,1410
+scale: 6
+:part
+
+:sprite

cmd/krampus19/res/sprites/particles.txt

@@ -0,0 +1,11 @@
+sprite:
+texture: particles
+
+part:
+name: splash
+sub_texture: 0,0,96,96
+anchor: 48,48
+scale: 6
+:part
+
+:sprite

cmd/krampus19/res/sprites/ui.txt

@@ -0,0 +1,32 @@
+sprite:
+texture: ui
+
+part:
+name: square
+sub_texture: 0,0,448,512
+anchor: 224,256
+scale: 16
+:part
+
+part:
+name: check-square
+sub_texture: 0,512,448,512
+anchor: 224,768
+scale: 16
+:part
+
+part:
+name: angle-left
+sub_texture: 768,0,192,512
+anchor: 848,196
+scale: 16
+:part
+
+part:
+name: angle-right
+sub_texture: 768,512,192,512
+anchor: 848,720
+scale: 16
+:part
+
+:sprite

cmd/krampus19/settings.go

@@ -1,10 +1,8 @@
 package main
 
-import "opslag.de/schobers/allg5"
-
-type settings struct {
-	Controls controls
-}
+import (
+	"opslag.de/schobers/allg5"
+)
 
 func newDefaultSettings() settings {
 	return settings{
@@ -14,9 +12,48 @@ func newDefaultSettings() settings {
 			MoveDown:  allg5.KeyDown,
 			MoveLeft:  allg5.KeyLeft,
 		},
+		Video: video{
+			Windowed:    true,
+			DisplayMode: "",
+		},
 	}
 }
 
+type settings struct {
+	Controls controls
+	Video    video
+}
+
+func (s *settings) DefaultPath() (string, error) { return userFile("settings.json") }
+
+func (s *settings) Load(path string) error {
+	var fromFile settings
+	err := decodeJSON(path, &fromFile)
+	if err != nil {
+		return err
+	}
+	*s = fromFile
+	return nil
+}
+
+func (s *settings) LoadDefault() error {
+	path, err := s.DefaultPath()
+	if err != nil {
+		return err
+	}
+	return s.Load(path)
+}
+
+func (s *settings) Store(path string) error { return encodeJSON(path, s) }
+
+func (s *settings) StoreDefault() error {
+	path, err := s.DefaultPath()
+	if err != nil {
+		return err
+	}
+	return s.Store(path)
+}
+
 type controls struct {
 	MoveUp    allg5.Key
 	MoveRight allg5.Key
@@ -24,6 +61,11 @@ type controls struct {
 	MoveLeft  allg5.Key
 }
 
+type video struct {
+	Windowed    bool
+	DisplayMode string
+}
+
 func (c controls) MovementKeys() []allg5.Key {
 	return []allg5.Key{c.MoveUp, c.MoveRight, c.MoveDown, c.MoveLeft}
 }

cmd/krampus19/splash.go

@@ -1,11 +1,8 @@
 package main
 
 import (
-	"math"
 	"time"
 
-	"opslag.de/schobers/allg5"
-
 	"opslag.de/schobers/geom"
 	"opslag.de/schobers/krampus19/alui"
 )
@@ -20,26 +17,5 @@ type splash struct {
 }
 
 func (s *splash) Render(ctx *alui.Context, bounds geom.RectangleF32) {
-	var dragon = s.ctx.Sprites["dragon"]
-
-	var texture = s.ctx.Textures[dragon.texture]
-	var body = texture.Subs["body"]
-	var upperWing = texture.Subs["upper_wing"]
-	var lowerWing = texture.Subs["lower_wing"]
-	var foot = texture.Subs["foot"]
-
-	scale := bounds.Dy() / 1600
-
-	var repeat = 2 * time.Second / time.Millisecond
-	var tick = float64((s.ctx.Tick / time.Millisecond) % repeat)
-	flap := .5*float32(math.Cos(tick*2*math.Pi/float64(repeat))) + .5 // [0..1]
-	upperFlap := flap*.75 + .25                                       // [.25..1]
-	lowerFlap := flap*.5 + .5                                         // [.5..1]
-
-	body.DrawOptions(0, 0, allg5.DrawOptions{Scale: allg5.NewUniformScale(scale)})
-	foot.DrawOptions(750*scale, 500*scale, allg5.DrawOptions{Scale: allg5.NewUniformScale(scale)})
-
-	var upperWingOffset = float32(upperWing.Height()) * scale * (1 - flap) * .8
-	upperWing.DrawOptions(750*scale, -100*scale+upperWingOffset, allg5.DrawOptions{Scale: allg5.NewScale(scale, scale*upperFlap)})
-	lowerWing.DrawOptions(750*scale, -100*scale+upperWingOffset*.95, allg5.DrawOptions{Scale: allg5.NewScale(scale, scale*lowerFlap)})
+	s.atEnd = true
 }

cmd/krampus19/sprite.go

@@ -7,6 +7,7 @@ import (
 	"strings"
 
 	"opslag.de/schobers/geom"
+	"opslag.de/schobers/krampus19/gut"
 )
 
 type sprite struct {
@@ -14,16 +15,26 @@ type sprite struct {
 	parts   []spritePart
 }
 
+func (s sprite) FindPartByName(name string) spritePart {
+	for _, part := range s.parts {
+		if part.name == name {
+			return part
+		}
+	}
+	return spritePart{}
+}
+
 type spritePart struct {
 	name   string
 	sub    geom.Rectangle
 	anchor geom.Point
+	scale  float32
 }
 
 func loadSpriteAsset(r io.Reader) (sprite, error) {
 	var l sprite
 	ctx := spriteContext{&l, nil}
-	err := parseLines(r, ctx.parse)
+	err := gut.ParseLines(r, ctx.parse)
 	if err != nil {
 		return sprite{}, err
 	}
@@ -35,51 +46,51 @@ type spriteContext struct {
 	part   *spritePart
 }
 
-func (c *spriteContext) parse(p *lineParser) parseLineFn {
-	if p.skipSpaceEOF() {
+func (c *spriteContext) parse(p *gut.LineParser) gut.ParseLineFn {
+	if p.SkipSpaceEOF() {
 		return nil
 	}
-	line := p.peek()
+	line := p.Peek()
 	switch {
 	case strings.HasPrefix(line, "sprite:"):
-		p.next()
+		p.Next()
 		return c.parseContent
 	default:
 		return nil
 	}
 }
 
-func (c *spriteContext) parseContent(p *lineParser) parseLineFn {
+func (c *spriteContext) parseContent(p *gut.LineParser) gut.ParseLineFn {
 	const partTag = "part:"
 	const textureTag = "texture:"
 	const spriteEndTag = ":sprite"
-	if p.skipSpaceEOF() {
-		return p.emitErr(errUnexpectedEnd)
+	if p.SkipSpaceEOF() {
+		return p.EmitErr(gut.ErrUnexpectedEnd)
 	}
-	line := p.peek()
+	line := p.Peek()
 	switch {
 	case strings.HasPrefix(line, textureTag):
 		c.sprite.texture = strings.TrimSpace(line[len(textureTag):])
-		p.next()
+		p.Next()
 		return c.parseContent
 	case line == partTag:
-		p.next()
+		p.Next()
 		c.part = &spritePart{}
 		return c.parsePart
 	case line == spriteEndTag:
 		return nil
 	}
-	return p.emitErr(errors.New("unexpected content of sprite"))
+	return p.EmitErr(errors.New("unexpected content of sprite"))
 }
 
-func (c *spriteContext) parsePart(p *lineParser) parseLineFn {
+func (c *spriteContext) parsePart(p *gut.LineParser) gut.ParseLineFn {
 	mustAtois := func(s ...string) []int {
 		res := make([]int, len(s))
 		var err error
 		for i, s := range s {
 			res[i], err = strconv.Atoi(s)
 			if err != nil {
-				panic("string does not represent an integer")
+				panic("string does not represent an integer number")
 			}
 		}
 		return res
@@ -88,18 +99,26 @@ func (c *spriteContext) parsePart(p *lineParser) parseLineFn {
 		coords := strings.Split(strings.TrimSpace(s), ",")
 		return mustAtois(coords...)
 	}
+	mustAtof := func(s string) float32 {
+		f, err := strconv.ParseFloat(strings.TrimSpace(s), 32)
+		if err != nil {
+			panic("string does not represent an floating point number")
+		}
+		return float32(f)
+	}
 	const nameTag = "name:"
 	const subTextureTag = "sub_texture:"
 	const anchorTag = "anchor:"
+	const scaleTag = "scale:"
 	const partEndTag = ":part"
-	if p.skipSpaceEOF() {
-		return p.emitErr(errUnexpectedEnd)
+	if p.SkipSpaceEOF() {
+		return p.EmitErr(gut.ErrUnexpectedEnd)
 	}
-	line := p.peek()
+	line := p.Peek()
 	switch {
 	case strings.HasPrefix(line, nameTag):
 		c.part.name = strings.TrimSpace(line[len(nameTag):])
-		p.next()
+		p.Next()
 		return c.parsePart
 	case strings.HasPrefix(line, subTextureTag):
 		var coords = mustCoords(line[len(subTextureTag):])
@@ -107,7 +126,7 @@ func (c *spriteContext) parsePart(p *lineParser) parseLineFn {
 			panic("expected four coordinates (min x, min y, size x, size y)")
 		}
 		c.part.sub = geom.Rect(coords[0], coords[1], coords[0]+coords[2], coords[1]+coords[3])
-		p.next()
+		p.Next()
 		return c.parsePart
 	case strings.HasPrefix(line, anchorTag):
 		var coords = mustCoords(line[len(anchorTag):])
@@ -115,12 +134,16 @@ func (c *spriteContext) parsePart(p *lineParser) parseLineFn {
 			panic("expected two coordinates (min x, min y)")
 		}
 		c.part.anchor = geom.Pt(coords[0], coords[1])
-		p.next()
+		p.Next()
+		return c.parsePart
+	case strings.HasPrefix(line, scaleTag):
+		c.part.scale = mustAtof(line[len(scaleTag):])
+		p.Next()
 		return c.parsePart
 	case line == partEndTag:
 		c.sprite.parts = append(c.sprite.parts, *c.part)
-		p.next()
+		p.Next()
 		return c.parseContent
 	}
-	return p.emitErr(errors.New("unexpected content of part"))
+	return p.EmitErr(errors.New("unexpected content of part"))
 }

cmd/krampus19/spritedrawer.go

@@ -0,0 +1,69 @@
+package main
+
+import (
+	"opslag.de/schobers/allg5"
+	"opslag.de/schobers/geom"
+)
+
+type DrawSpriteOptions struct {
+	Scale float32
+	Tint  *allg5.Color
+}
+
+type SpriteDrawer struct {
+	ctx *Context
+}
+
+func (d SpriteDrawer) scale(sprite, user float32) float32 {
+	var scale float32 = 1
+	if sprite != 0 {
+		scale *= 1 / sprite
+	}
+	if user != 0 {
+		scale *= user
+	}
+	return scale
+}
+
+func (d SpriteDrawer) Draw(name, partName string, pos geom.PointF32, opts DrawSpriteOptions) bool {
+	sprite, ok := d.ctx.Sprites[name]
+	if !ok {
+		return false
+	}
+	text, ok := d.ctx.Textures[sprite.texture]
+	if !ok {
+		return false
+	}
+	partText, ok := text.Subs[partName]
+	if !ok {
+		return false
+	}
+	part := sprite.FindPartByName(partName)
+	scale := d.scale(part.scale, opts.Scale)
+	anchor := part.sub.Min.Sub(part.anchor).ToF32().Mul(scale)
+	scrPos := pos.Add(anchor)
+	left, top := scrPos.X, scrPos.Y
+	var drawOpts allg5.DrawOptions
+	if scale != 1 {
+		drawOpts.Scale = allg5.NewUniformScale(scale)
+	}
+	if opts.Tint != nil {
+		drawOpts.Tint = opts.Tint
+	}
+	partText.DrawOptions(left, top, drawOpts)
+	return true
+}
+
+func (d SpriteDrawer) Size(name, partName string) geom.PointF32 {
+	return d.SizeScale(name, partName, 0)
+}
+
+func (d SpriteDrawer) SizeScale(name, partName string, scale float32) geom.PointF32 {
+	sprite, ok := d.ctx.Sprites[name]
+	if !ok {
+		return geom.PointF32{}
+	}
+	part := sprite.FindPartByName(partName)
+	scale = d.scale(part.scale, scale)
+	return part.sub.Size().ToF32().Mul(scale)
+}

cmd/tilewarp/tilewarp.go

@@ -0,0 +1,148 @@
+package main
+
+import (
+	"image"
+	"image/color"
+	"image/png"
+	"log"
+	"os"
+)
+
+func main() {
+	err := run()
+	if err != nil {
+		log.Fatal(err)
+	}
+}
+
+func loadPNG(path string) (image.Image, error) {
+	f, err := os.Open(path)
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+	return png.Decode(f)
+}
+
+func storePNG(path string, im image.Image) error {
+	f, err := os.Create(path)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	return png.Encode(f, im)
+}
+
+type warpFn func(image.Image) image.Image
+
+func warp(path string, warp warpFn) error {
+	im, err := loadPNG(path)
+	if err != nil {
+		return err
+	}
+	warped := warp(im)
+	return storePNG(path, warped)
+}
+
+type warpTile struct {
+	im image.Image
+
+	right    int
+	farRight int
+	top      int
+	farTop   int
+
+	src tile
+	dst tile
+
+	yOffset int
+}
+
+type tile struct {
+	width  int
+	height int
+}
+
+func (w warpTile) ColorModel() color.Model { return w.im.ColorModel() }
+
+func (w warpTile) Bounds() image.Rectangle {
+	bounds := w.im.Bounds()
+	bounds.Max.Y = bounds.Dy() * w.dst.height / w.src.height
+	return bounds
+}
+
+func (w warpTile) At(x, y int) color.Color {
+	offset := image.Point{}
+	for x >= w.dst.width {
+		x -= w.dst.width
+		offset.X += w.src.width
+	}
+	for y >= w.dst.height {
+		y -= w.dst.height
+		offset.Y += w.src.height
+	}
+	y += w.yOffset
+
+	if y >= w.top && x < w.right {
+		return w.im.At(x+offset.X, y-6*30+offset.Y)
+	}
+
+	isTopSide := func() bool {
+		if y >= w.top {
+			return false
+		}
+		if x < w.right {
+			return true
+		}
+		sideX := w.farRight - (w.farRight-w.right)*(y-w.farTop)/(w.top-w.farTop)
+		return x < sideX
+	}
+	if isTopSide() {
+		srcY := w.farTop + (6*40)*(y-w.farTop)/(w.top-w.farTop)
+		return w.im.At(x+offset.X, srcY+offset.Y)
+	}
+	srcY := y - (6*30)*(w.farRight-x)/(w.farRight-w.right)
+	srcBottom := 6 * 160
+	if srcY > srcBottom {
+		srcY = srcBottom
+	}
+	return w.im.At(x+offset.X, srcY+offset.Y)
+}
+
+func run() error {
+	warp("../krampus19/res/tile_lava_brick.png", func(im image.Image) image.Image {
+		return &warpTile{
+			im:       im,
+			dst:      tile{width: 6 * 170, height: 6 * 190},
+			src:      tile{width: 6 * 170, height: 6 * 160},
+			right:    6 * 110,
+			farRight: 6 * 160,
+			top:      6 * 80,
+			farTop:   6 * 10,
+		}
+	})
+	warp("../krampus19/res/tile_magma.png", func(im image.Image) image.Image {
+		return &warpTile{
+			im:       im,
+			dst:      tile{width: 6 * 170, height: 6 * 190},
+			src:      tile{width: 6 * 170, height: 6 * 160},
+			right:    6 * 110,
+			farRight: 6 * 160,
+			top:      6 * 100,
+			farTop:   6 * 30,
+		}
+	})
+	warp("../krampus19/res/entity_brick.png", func(im image.Image) image.Image {
+		return &warpTile{
+			im:       im,
+			dst:      tile{width: 6 * 170, height: 6 * 190},
+			src:      tile{width: 6 * 170, height: 6 * 160},
+			yOffset:  18,
+			right:    6 * 100,
+			farRight: 6 * 150,
+			top:      6 * 100,
+			farTop:   6 * 30,
+		}
+	})
+	return nil
+}

gut/animation.go

@@ -18,10 +18,6 @@ type animation struct {
 	done  AnimationDoneFn
 }
 
-func (a *Animations) Idle() bool {
-	return len(a.anis) == 0
-}
-
 func (a *Animations) Start(now time.Duration, ani Animation) {
 	a.StartFn(now, ani, nil)
 }

gut/console.go

@@ -13,6 +13,9 @@ type Console struct {
 
 func (c *Console) Write(p []byte) (int, error) {
 	c.messages = append(c.messages, string(bytes.TrimRight(p, "\r\n")))
+	if len(c.messages) > 1000 {
+		c.messages = c.messages[1:]
+	}
 	return len(p), nil
 }
 

gut/lineparser.go

@@ -0,0 +1,66 @@
+package gut
+
+import (
+	"errors"
+	"io"
+	"io/ioutil"
+	"strings"
+)
+
+type LineParser struct {
+	lines []string
+	i     int
+	err   error
+}
+
+var ErrUnexpectedEnd = errors.New("unexpected end of file")
+
+func (p *LineParser) EOF() bool { return p.i == len(p.lines) }
+
+func (p *LineParser) EmitErr(err error) ParseLineFn {
+	p.err = err
+	return nil
+}
+
+func (p *LineParser) Next() string {
+	i := p.i
+	p.i++
+	return p.lines[i]
+}
+
+func (p *LineParser) Peek() string { return p.lines[p.i] }
+
+func (p *LineParser) SkipSpaceEOF() bool {
+	for !p.EOF() && len(strings.TrimSpace(p.Peek())) == 0 {
+		p.Next()
+	}
+	return p.EOF()
+}
+
+func SkipSpaceBeforeContent(next ParseLineFn) ParseLineFn {
+	return func(p *LineParser) ParseLineFn {
+		if p.SkipSpaceEOF() {
+			return p.EmitErr(ErrUnexpectedEnd)
+		}
+		return next
+	}
+}
+
+type ParseLineFn func(p *LineParser) ParseLineFn
+
+func ParseLines(r io.Reader, fn ParseLineFn) error {
+	content, err := ioutil.ReadAll(r)
+	if err != nil {
+		return err
+	}
+	lines := strings.Split(string(content), "\n")
+	for i, line := range lines {
+		lines[i] = strings.TrimRight(line, "\r\n")
+	}
+
+	parser := &LineParser{lines: lines}
+	for fn != nil {
+		fn = fn(parser)
+	}
+	return parser.err
+}

soko/direction.go

@@ -0,0 +1,64 @@
+package soko
+
+import "opslag.de/schobers/geom"
+
+type Direction int
+
+const (
+	DirectionUp Direction = iota
+	DirectionRight
+	DirectionDown
+	DirectionLeft
+)
+
+var Directions = [4]Direction{DirectionUp, DirectionRight, DirectionDown, DirectionLeft}
+
+func (d Direction) Invert() Direction {
+	switch d {
+	case DirectionUp:
+		return DirectionDown
+	case DirectionRight:
+		return DirectionLeft
+	case DirectionDown:
+		return DirectionUp
+	case DirectionLeft:
+		return DirectionRight
+	}
+	panic("invalid direction")
+}
+
+func (d Direction) String() string {
+	switch d {
+	case DirectionUp:
+		return "up"
+	case DirectionRight:
+		return "right"
+	case DirectionDown:
+		return "down"
+	case DirectionLeft:
+		return "left"
+	}
+	return "invalid"
+}
+
+func (d Direction) ToPoint() geom.Point {
+	switch d {
+	case DirectionUp:
+		return geom.Pt(0, -1)
+	case DirectionRight:
+		return geom.Pt(1, 0)
+	case DirectionDown:
+		return geom.Pt(0, 1)
+	case DirectionLeft:
+		return geom.Pt(-1, 0)
+	}
+	return geom.Point{}
+}
+
+func Neighbours(p geom.Point) []geom.Point {
+	neighbours := make([]geom.Point, 4)
+	for i, dir := range Directions {
+		neighbours[i] = p.Add(dir.ToPoint())
+	}
+	return neighbours
+}

soko/entity.go

@@ -0,0 +1,48 @@
+package soko
+
+type Entity struct {
+	ID  int
+	Pos int
+	Typ EntityType
+}
+
+type Entities []Entity
+
+func (e Entities) ByID(id int) Entity {
+	idx := e.IdxById(id)
+	if idx == -1 {
+		return Entity{ID: -1}
+	}
+	return e[idx]
+}
+
+func (e Entities) Clone() Entities {
+	clone := make(Entities, len(e))
+	copy(clone, e)
+	return clone
+}
+
+func (e Entities) IdxById(id int) int {
+	for i, e := range e {
+		if e.ID == id {
+			return i
+		}
+	}
+	return -1
+}
+
+type Ints []int
+
+func NewInts(n int) Ints {
+	ids := make(Ints, n)
+	for i := range ids {
+		ids[i] = -1
+	}
+	return ids
+}
+
+func (e Ints) Clone() Ints {
+	clone := make(Ints, len(e))
+	copy(clone, e)
+	return clone
+}

soko/entitylocations.go

@@ -0,0 +1,31 @@
+package soko
+
+import "opslag.de/schobers/geom"
+
+type EntityLocations map[geom.Point]int
+
+func (l EntityLocations) Add(p geom.Point, id int) { l[p] = id }
+
+func (l EntityLocations) Clone() EntityLocations {
+	clone := EntityLocations{}
+	for p, id := range l {
+		clone[p] = id
+	}
+	return clone
+}
+
+func (l EntityLocations) Has(p geom.Point) bool {
+	_, ok := l[p]
+	return ok
+}
+
+func (l EntityLocations) Move(from, to geom.Point) {
+	id, ok := l[from]
+	if !ok {
+		panic("no entitiy at position")
+	}
+	l.Remove(from)
+	l.Add(to, id)
+}
+
+func (l EntityLocations) Remove(p geom.Point) { delete(l, p) }

soko/entitytype.go

@@ -0,0 +1,23 @@
+package soko
+
+type EntityType byte
+
+const (
+	EntityTypeInvalid EntityType = EntityType(0)
+	EntityTypeNone               = '_'
+	EntityTypePlayer             = '@'
+	EntityTypeTarget             = 'X'
+	EntityTypeBrick              = 'B'
+)
+
+func (e EntityType) IsValid() bool {
+	switch e {
+	case EntityTypeNone:
+	case EntityTypePlayer:
+	case EntityTypeTarget:
+	case EntityTypeBrick:
+	default:
+		return false
+	}
+	return true
+}

soko/level.go

@@ -0,0 +1,91 @@
+package soko
+
+import (
+	"opslag.de/schobers/geom"
+)
+
+type Level struct {
+	Width  int
+	Height int
+
+	Tiles    []TileType
+	Entities []EntityType
+}
+
+func (l Level) IdxToPos(i int) geom.Point { return geom.Pt(i%l.Width, i/l.Width) }
+
+func (l Level) PosToIdx(p geom.Point) int {
+	if p.X < 0 || p.Y < 0 || p.X >= l.Width || p.Y >= l.Height {
+		return -1
+	}
+	return p.Y*l.Width + p.X
+}
+
+func (l Level) Moves() []Moves {
+	moves := make([]Moves, len(l.Tiles))
+	w := l.Width
+	for y := 0; y < l.Height; y++ {
+		for x := 0; x < w; x++ {
+			var m Moves
+			idx := y*w + x
+			if y > 0 {
+				m.Valid = append(m.Valid, idx-w)
+				m.All[DirectionUp] = idx - w
+			} else {
+				m.All[DirectionUp] = -1
+			}
+			if y < (l.Height - 1) {
+				m.Valid = append(m.Valid, idx+w)
+				m.All[DirectionDown] = idx + w
+			} else {
+				m.All[DirectionDown] = -1
+			}
+			if x > 0 {
+				m.Valid = append(m.Valid, idx-1)
+				m.All[DirectionLeft] = idx - 1
+			} else {
+				m.All[DirectionLeft] = idx - 1
+			}
+			if x < (w - 1) {
+				m.Valid = append(m.Valid, idx+1)
+				m.All[DirectionRight] = idx + 1
+			} else {
+				m.All[DirectionRight] = idx + 1
+			}
+			moves[idx] = m
+		}
+	}
+	return moves
+}
+
+func (l Level) MoveIdx(idx int, dir Direction) int {
+	switch dir {
+	case DirectionUp:
+		if idx < l.Width {
+			return -1
+		}
+		return idx - l.Width
+	case DirectionRight:
+		if (idx+1)%l.Width == 0 {
+			return -1
+		}
+		return idx + 1
+	case DirectionDown:
+		if idx >= (l.Width*l.Height)-l.Width {
+			return -1
+		}
+		return idx + l.Width
+	case DirectionLeft:
+		if idx%l.Width == 0 {
+			return -1
+		}
+		return idx - 1
+	}
+	return -1
+}
+
+func (l Level) Size() int { return l.Width * l.Height }
+
+func (l Level) State() State {
+	return NewState(l)
+}

soko/levelparser.go

@@ -0,0 +1,85 @@
+package soko
+
+import (
+	"errors"
+	"fmt"
+	"io"
+
+	"opslag.de/schobers/krampus19/gut"
+)
+
+func ParseLevel(r io.Reader) (Level, error) {
+	var l Level
+	ctx := levelContext{&l}
+	err := gut.ParseLines(r, ctx.parse)
+	if err != nil {
+		return Level{}, err
+	}
+	return l, nil
+}
+
+type levelContext struct {
+	level *Level
+}
+
+func (c *levelContext) parse(p *gut.LineParser) gut.ParseLineFn {
+	if p.EOF() {
+		return nil
+	}
+	switch p.Peek() {
+	case "level:":
+		return c.parseContent
+	case "":
+		p.Next() // skip
+		return c.parse
+	default:
+		return nil
+	}
+}
+
+func (c *levelContext) parseContent(p *gut.LineParser) gut.ParseLineFn {
+	if p.Next() != "level:" {
+		return p.EmitErr(errors.New("expected level start"))
+	}
+	return c.parseRow
+}
+
+func (c *levelContext) parseRow(p *gut.LineParser) gut.ParseLineFn {
+	if p.EOF() {
+		return p.EmitErr(errors.New("unexpected end of file"))
+	}
+	line := p.Next()
+	if line == ":level" {
+		return c.parse
+	}
+	if c.level.Height == 0 {
+		c.level.Width = len(line) / 2
+	}
+	return c.addRow(p, line)
+}
+
+func (c *levelContext) addRow(p *gut.LineParser, line string) gut.ParseLineFn {
+	var tiles []TileType
+	var entities []EntityType
+	for i := 0; i < len(line); i += 2 {
+		tiles = append(tiles, TileType(line[i]))
+		entities = append(entities, EntityType(line[i+1]))
+	}
+
+	for i, t := range tiles {
+		if !t.IsValid() {
+			return p.EmitErr(fmt.Errorf("level contains invalid TileType at (%d, %d)", i, c.level.Height))
+		}
+	}
+	for i, e := range entities {
+		if !e.IsValid() {
+			return p.EmitErr(fmt.Errorf("level contains invalid entity type at (%d, %d)", i, c.level.Height))
+		}
+	}
+
+	c.level.Height++
+	c.level.Tiles = append(c.level.Tiles, tiles...)
+	c.level.Entities = append(c.level.Entities, entities...)
+
+	return c.parseRow
+}

soko/locations.go

@@ -0,0 +1,17 @@
+package soko
+
+import "opslag.de/schobers/geom"
+
+type Locations map[geom.Point]bool
+
+func (l Locations) Add(p geom.Point) { l[p] = true }
+
+func (l Locations) Clone() Locations {
+	clone := Locations{}
+	for p := range l {
+		clone[p] = true
+	}
+	return clone
+}
+
+func (l Locations) Remove(p geom.Point) { delete(l, p) }

soko/moves.go

@@ -0,0 +1,6 @@
+package soko
+
+type Moves struct {
+	All   [4]int
+	Valid []int
+}

soko/pathfinder.go

@@ -0,0 +1,133 @@
+package soko
+
+import (
+	"sort"
+)
+
+type PathFinder struct {
+	state *State
+	moves []Moves
+}
+
+func NewPathFinder(s *State) PathFinder {
+	return PathFinder{s, nil}
+}
+
+func NewPathFinderMoves(s *State, moves []Moves) PathFinder {
+	return PathFinder{s, moves}
+}
+
+func (p PathFinder) Find(target int) []int {
+	source := p.state.Player.Pos
+	level := p.state.Level
+	size := level.Size()
+	distances := NewInts(size)
+	distances[source] = 0
+	moves := NewInts(size)
+	moves[source] = source
+	state := p.newPathFinderState(source)
+
+	heuristic := func(i int) int {
+		idx := state.frontier[i]
+		return distances[idx] + p.state.IdxToPos[idx].DistInt(p.state.IdxToPos[target])
+	}
+	for {
+		curr := state.frontier[0]
+		if curr == target {
+			break
+		}
+		state.frontier = state.frontier[1:]
+
+		state.findBetterNeighbours(distances, curr, func(nextIdx, newDistance int) {
+			moves[nextIdx] = curr
+		})
+
+		if len(state.frontier) == 0 {
+			return nil // no path
+		}
+
+		// apply heuristic to frontier (favor points closer to target)
+		sort.Slice(state.frontier, func(i, j int) bool { return heuristic(i) < heuristic(j) })
+	}
+
+	// build reverse path
+	curr := target
+	path := []int{curr}
+	for {
+		curr = moves[curr]
+		if curr == source {
+			break
+		}
+		path = append(path, curr)
+	}
+	// reverse path
+	n := len(path)
+	for i := 0; i < n/2; i++ {
+		path[i], path[n-i-1] = path[n-i-1], path[i]
+	}
+	return path
+}
+
+func (p PathFinder) FindDistances() Ints {
+	source := p.state.Player.Pos
+	level := p.state.Level
+	size := level.Size()
+	distances := NewInts(size)
+	distances[source] = 0
+	state := p.newPathFinderState(source)
+
+	for {
+		curr := state.frontier[0]
+		state.frontier = state.frontier[1:]
+
+		state.findBetterNeighbours(distances, curr, nil)
+
+		if len(state.frontier) == 0 {
+			return distances
+		}
+	}
+}
+
+func (p PathFinder) newPathFinderState(source int) *pathFinderState {
+	return &pathFinderState{p.state, append(make([]int, 0, p.state.Level.Size()), source), p.moves}
+}
+
+type pathFinderState struct {
+	state    *State
+	frontier []int
+	moves    []Moves
+}
+
+type betterNeighbourFn func(int, int)
+
+func (s *pathFinderState) findBetterNeighbours(distances []int, curr int, better betterNeighbourFn) {
+	currDistance := distances[curr]
+	newDistance := currDistance + 1
+
+	var moves []int
+	if s.moves == nil {
+		for _, dir := range Directions {
+			nextIdx := s.state.Level.MoveIdx(curr, dir)
+			if nextIdx == -1 {
+				continue
+			}
+			moves = append(moves, nextIdx)
+		}
+	} else {
+		moves = s.moves[curr].Valid
+	}
+	for _, nextIdx := range moves {
+		if distance := distances[nextIdx]; distance != -1 && distance <= newDistance { // skip when shorter path exists
+			continue
+		}
+		if !s.state.Walkable[nextIdx] || s.state.Bricks[nextIdx] != -1 { // filter neighbours
+			continue
+		}
+		distances[nextIdx] = newDistance
+		s.frontier = append(s.frontier, nextIdx)
+		if better == nil {
+			continue
+		}
+		better(nextIdx, newDistance)
+	}
+}

soko/solver.go

@@ -0,0 +1,94 @@
+package soko
+
+func Solve(l Level) int {
+	state := l.State()
+	return solve(state)
+}
+
+func solve(state State) int {
+	level := state.Level
+	target := state.Target.Pos
+	costs := &stateCostQueue{}
+	costs.Put(&stateCost{&state, 0, nil})
+	costsByPlayerIdx := make([][]*stateCost, level.Size())
+	findCost := func(s *State) *stateCost {
+		costs := costsByPlayerIdx[s.Player.Pos]
+		for i := 0; i < len(costs); i++ {
+			if !costs[i].state.Equal(s) {
+				continue
+			}
+			return costs[i]
+		}
+		return nil
+	}
+	addCost := func(next *State, nextCost int) {
+		cost := findCost(next)
+		if cost == nil {
+			newCost := &stateCost{next, nextCost, nil}
+			costs.Put(newCost)
+			player := next.Player.Pos
+			costsByPlayerIdx[player] = append(costsByPlayerIdx[player], newCost)
+		} else if nextCost < cost.cost {
+			cost.cost = nextCost
+			costs.Update(cost)
+		}
+	}
+	moves := level.Moves()
+	type direction struct {
+		dir     Direction
+		inverse Direction
+	}
+	dirs := make([]direction, 4)
+	for _, dir := range Directions {
+		dirs[dir] = direction{dir, dir.Invert()}
+	}
+	for {
+		curr := costs.Get()
+		currPlayerPos := curr.state.Player.Pos
+		if currPlayerPos == target {
+			return curr.cost
+		}
+
+		if curr.distances == nil {
+			curr.distances = NewPathFinderMoves(curr.state, moves).FindDistances()
+		}
+		distances := curr.distances
+		for _, e := range curr.state.Entities {
+			idx := e.Pos
+			if e.Typ != EntityTypeBrick || curr.state.SunkenBricks[idx] == e.ID {
+				continue
+			}
+			for i := 0; i < 4; i++ {
+				player := moves[e.Pos].All[dirs[i].inverse]
+				if player == -1 {
+					continue
+				}
+				walk := distances[player]
+				if walk == -1 {
+					continue
+				}
+				if !curr.state.IsOpenForBrick(curr.state.IdxToPos[moves[e.Pos].All[i]]) {
+					continue
+				}
+				curr.state.Player.Pos = player
+				next, ok := curr.state.MovePlayer(dirs[i].dir)
+				if !ok {
+					panic("should be a valid move")
+				}
+				nextCost := curr.cost + walk + 1
+				addCost(&next, nextCost)
+			}
+		}
+		curr.state.Player.Pos = currPlayerPos
+		if walk := distances[target]; walk != -1 {
+			next := curr.state.Clone()
+			next.Player.Pos = target
+			nextCost := curr.cost + walk
+			addCost(&next, nextCost)
+		}
+
+		if costs.Empty() {
+			return -1
+		}
+	}
+}

soko/solver_test.go

@@ -0,0 +1,111 @@
+package soko
+
+import (
+	"bytes"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+var levelBenchmark = `level:
+._._._._._._._._._._._._._._._._._._._._
+._._._._._#_#_#_._._._._._._._._._._._._
+._._._._._#_#_#_._._._._._._._._._._._._
+._._._._._#_#_#_._._._._._._._._._._._._
+._._._#_#_#_#_#_#_._._._._._._._._._._._
+._._._#_._#_._._#_._._._._#X#_#_~_#_#_._
+._#_#_#_._#_._._#_._._._._._._._~_#_#_._
+._#_#B#_#_#B#_#_#_#_#_#_#_#_#_#_#_#_#_._
+._._._._._#_._._._#_._#@._._._._#_#_._._
+._._._._._#_#_#_#_#_._._._._._._._._._._
+._._._._._._._._._._._._._._._._._._._._
+:level`
+
+var levelEasy = `level:
+._._._._._._._._._._
+._#@#_#_#B#_~_#_#X._
+._._._._._._._._._._
+:level`
+
+var level1 = `level:
+._._._._._._._._._._
+._#_#_#_#_~_~_~_#_._
+._#_#_._#B~_~_#_#_._
+._#_#_#_#_~_~_~_#_._
+._#_#_._#B~_~_#_#_._
+._#@#_#_#_~_~_#_#X._
+._#_#_~_~_~_#_#_#_._
+._#_#_~_~_~_#_#_#_._
+._._._._._._._._._._
+:level`
+
+var level2 = `level:
+._._._._._._._._._._._._._._._._._._._._
+._._._._._#_#_#_._._._._._._._._._._._._
+._._._._._#B#_#_._._._._._._._._._._._._
+._._._._._#_#_#B._._._._._._._._._._._._
+._._._#_#_#B#_#B#_._._._._._._._._._._._
+._._._#_._#_._._#_._._._._#X#_~_~_~_#_._
+._#_#_#_._#_._._#_._._._._._._._~_~_#_._
+._#_#B#_#_#B#_#_#_#_#_#_#_#_#_#_~_#_#_._
+._._._._._#_._._._#_._#@._._._._#_#_._._
+._._._._._#_#_#_#_#_._._._._._._._._._._
+._._._._._._._._._._._._._._._._._._._._
+:level`
+
+var level3 = `level:
+._._._._._._._._._._
+._._._._._._._._._._
+._~_#_#_#_#B#_._._._
+._~_#B#_#_._#_._._._
+._~_._#_~_#_#_._._._
+._#X._#_~_#_._._._._
+._._#_#B#_#_._._._._
+._._#@#_._._._._._._
+._._._._._._._._._._
+:level`
+
+var level4 = `level:
+._._._._._._._._._._._._
+._._#_#_._._._._._._._._
+._._#_#B#_#B#@#_#_._._._
+._._#_#_#_#_#B#_#_._._._
+._._._._._._#_._._._._._
+._._._._._._#_._._._._._
+._._._._._._#B._._._._._
+._._._#_#_._#_._#_#_._._
+._#_#_#_#_~_#_#_#_#_#_._
+._#_._._#_._#_._#_._#_._
+._#_._#X~_._~_._~_._#_._
+._#_._._#_._#_._#_._#_._
+._#_#_#_#_#_~_#_#_#_#_._
+._._._._._._._._._._._._
+:level`
+
+func mustParseLevel(s string) Level {
+	l, err := ParseLevel(bytes.NewBufferString(s))
+	if err != nil {
+		panic("couldn't parse level")
+	}
+	return l
+}
+
+func TestSolver(t *testing.T) {
+	solve := func(s string) int {
+		l := mustParseLevel(s)
+		steps := Solve(l)
+		return steps
+	}
+	assert.Equal(t, 7, solve(levelEasy))
+	assert.Equal(t, 35, solve(level1))
+	// assert.Equal(t, -1, solve(level2))
+	assert.Equal(t, 49, solve(level3))
+	// assert.Equal(t, -1, solve(level4))
+}
+
+func BenchmarkSolver(b *testing.B) {
+	l := mustParseLevel(levelBenchmark)
+	for n := 0; n < b.N; n++ {
+		Solve(l)
+	}
+}

soko/state.go

@@ -0,0 +1,240 @@
+package soko
+
+import "opslag.de/schobers/geom"
+
+type State struct {
+	Player Entity
+	Target Entity
+
+	Entities Entities
+
+	Level        Level
+	IdxToPos     []geom.Point
+	Bricks       Ints
+	SunkenBricks Ints
+	Walkable     []bool
+
+	nextEntityID int
+}
+
+func NewState(l Level) State {
+	size := l.Size()
+	s := State{
+		Entities:     Entities{},
+		Level:        l,
+		IdxToPos:     make([]geom.Point, size),
+		Bricks:       NewInts(size),
+		SunkenBricks: NewInts(size),
+		Walkable:     make([]bool, size),
+	}
+
+	for idx, t := range l.Tiles {
+		switch t {
+		case TileTypeBasic:
+			s.Walkable[idx] = true
+		}
+		s.IdxToPos[idx] = s.Level.IdxToPos(idx)
+	}
+
+	for idx, e := range l.Entities {
+		pos := s.IdxToPos[idx]
+		switch e {
+		case EntityTypeBrick:
+			s.addBrick(pos)
+		case EntityTypePlayer:
+			s.initPlayer(pos)
+		case EntityTypeTarget:
+			s.initTarget(pos)
+		}
+	}
+	return s
+}
+
+// Clone creates and returns a clone of the state.
+func (s State) Clone() State {
+	return State{
+		Player:       s.Player,
+		Target:       s.Target,
+		Entities:     s.Entities.Clone(),
+		Level:        s.Level,
+		IdxToPos:     s.IdxToPos,
+		Bricks:       s.Bricks.Clone(),
+		SunkenBricks: s.SunkenBricks.Clone(),
+		Walkable:     append(s.Walkable[:0:0], s.Walkable...),
+		nextEntityID: s.nextEntityID,
+	}
+}
+
+func (s State) All(pred func(State, geom.Point) bool, p ...geom.Point) bool {
+	for _, p := range p {
+		if !pred(s, p) {
+			return false
+		}
+	}
+	return true
+}
+
+func (s State) Any(pred func(State, geom.Point) bool, p ...geom.Point) bool {
+	for _, p := range p {
+		if pred(s, p) {
+			return true
+		}
+	}
+	return false
+}
+
+func (s *State) Equal(other *State) bool {
+	for i := 0; i < len(s.Entities); i++ {
+		if other.Entities[i].Pos != s.Entities[i].Pos {
+			return false
+		}
+	}
+	return true
+}
+
+func (s State) IsOpenForBrick(p geom.Point) bool {
+	idx := s.Level.PosToIdx(p)
+	if idx == -1 {
+		return false
+	}
+	return s.isOpenForBrick(idx)
+}
+
+// IsWalkable indicates that a player could walk over this tile regardless of any Bricks that might be there.
+func (s State) IsWalkable(p geom.Point) bool {
+	idx := s.Level.PosToIdx(p)
+	if idx == -1 {
+		return false
+	}
+	return s.Walkable[idx]
+}
+
+// IsWalkableAndFree indicates that a player can walk over this tile (no brick is at the tile).
+func (s State) IsWalkableAndFree(p geom.Point) bool {
+	idx := s.Level.PosToIdx(p)
+	if idx == -1 {
+		return false
+	}
+	return s.Walkable[idx] && s.Bricks[idx] == -1
+}
+
+// MovePlayer tries to move the player in the specified direction. Returns the new state and true if the move is valid. Returns the current state and false is the move was invalid.
+func (s State) MovePlayer(dir Direction) (State, bool) {
+	to := s.Level.MoveIdx(s.Player.Pos, dir)
+	if to == -1 {
+		return s, false
+	}
+
+	if !s.Walkable[to] {
+		return s, false
+	}
+
+	brickID := s.Bricks[to]
+	if brickID == -1 {
+		return s.Mutate(func(s *State) {
+			s.movePlayer(to)
+		}), true
+	}
+
+	brickTo := s.Level.MoveIdx(to, dir)
+	if brickTo == -1 {
+		return s, false
+	}
+	if !s.isOpenForBrick(brickTo) {
+		return s, false
+	}
+	return s.Mutate(func(s *State) {
+		s.movePlayer(to)
+
+		if s.Level.Tiles[brickTo] == TileTypeMagma && s.SunkenBricks[brickTo] == -1 {
+			s.SunkenBricks[brickTo] = brickID
+			s.Walkable[brickTo] = true
+			s.Bricks[to] = -1
+		} else {
+			s.Bricks[brickTo] = brickID
+			s.Bricks[to] = -1
+		}
+		s.updateEntity(brickID, Entity{brickID, brickTo, EntityTypeBrick})
+	}), true
+}
+
+func (s State) SetPlayer(to geom.Point) (State, bool) {
+	toIdx := s.Level.PosToIdx(to)
+	if toIdx == -1 {
+		return s, false
+	}
+	if !s.Walkable[toIdx] {
+		return s, false
+	}
+	if s.Bricks[toIdx] != -1 {
+		return s, false
+	}
+	return s.Mutate(func(s *State) {
+		s.movePlayer(toIdx)
+	}), true
+
+}
+
+// Mutate clones the state, applies the mutation on the clone and returns the clone.
+func (s State) Mutate(fn func(s *State)) State {
+	clone := s.Clone()
+	fn(&clone)
+	return clone
+}
+
+func (s *State) addBrick(pos geom.Point) {
+	s.addEntity(pos, EntityTypeBrick, func(e Entity) {
+		idx := s.Level.PosToIdx(pos)
+		if idx != -1 {
+			s.Bricks[idx] = e.ID
+		}
+	})
+}
+
+func (s *State) addEntity(pos geom.Point, typ EntityType, add func(Entity)) {
+	id := s.nextEntityID
+	e := Entity{id, s.Level.PosToIdx(pos), typ}
+	add(e)
+	s.Entities = append(s.Entities, e)
+	s.nextEntityID++
+}
+
+func (s *State) initPlayer(pos geom.Point) {
+	s.addEntity(pos, EntityTypePlayer, func(e Entity) {
+		s.Player = e
+	})
+}
+
+func (s *State) initTarget(pos geom.Point) {
+	s.addEntity(pos, EntityTypeTarget, func(e Entity) {
+		s.Target = e
+	})
+}
+
+func (s State) isOpenForBrick(idx int) bool {
+	if s.Walkable[idx] {
+		return s.Bricks[idx] == -1
+	}
+	return s.Level.Tiles[idx] == TileTypeMagma
+}
+
+func (s *State) updateEntity(id int, e Entity) {
+	idx := s.Entities.IdxById(id)
+	if idx == -1 {
+		return
+	}
+	s.Entities[idx] = e
+}
+
+func (s *State) movePlayer(to int) {
+	s.Player.Pos = to
+	s.updateEntity(s.Player.ID, Entity{s.Player.ID, to, EntityTypePlayer})
+}
+
+func IsMagma(s State, p geom.Point) bool {
+	idx := s.Level.PosToIdx(p)
+	if idx == -1 {
+		return false
+	}
+	return s.Level.Tiles[idx] == TileTypeMagma
+}

soko/statecost.go

@@ -0,0 +1,71 @@
+package soko
+
+type stateCost struct {
+	state     *State
+	cost      int
+	distances Ints
+}
+
+type stateCostQueue struct {
+	first *stateCostQueueItem
+}
+
+type stateCostQueueItem struct {
+	Value *stateCost
+	Next  *stateCostQueueItem
+}
+
+func (q *stateCostQueue) Empty() bool {
+	return q.first == nil
+}
+
+func (q *stateCostQueue) Get() *stateCost {
+	if q.Empty() {
+		panic("nothing in queue")
+	}
+	first := q.first
+	q.first = first.Next
+	return first.Value
+}
+
+func (q *stateCostQueue) Put(value *stateCost) {
+	priority := value.cost
+	item := &stateCostQueueItem{value, nil}
+	if q.Empty() {
+		q.first = item
+		return
+	}
+	if priority < q.first.Value.cost {
+		item.Next = q.first
+		q.first = item
+		return
+	}
+	curr := q.first
+	for curr.Next != nil {
+		if priority < curr.Next.Value.cost {
+			item.Next = curr.Next
+			curr.Next = item
+			return
+		}
+		curr = curr.Next
+	}
+	curr.Next = item
+}
+
+func (q *stateCostQueue) Update(value *stateCost) {
+	var prev *stateCostQueueItem
+	curr := q.first
+	for curr.Value != value {
+		prev = curr
+		curr = curr.Next
+		if curr == nil {
+			panic("not in queue")
+		}
+	}
+	if prev == nil {
+		q.first = curr.Next
+	} else {
+		prev.Next = curr.Next
+	}
+	q.Put(value)
+}

soko/tiletype.go

@@ -0,0 +1,21 @@
+package soko
+
+type TileType byte
+
+const (
+	TileTypeInvalid TileType = TileType(0)
+	TileTypeNothing          = '.'
+	TileTypeBasic            = '#'
+	TileTypeMagma            = '~'
+)
+
+func (t TileType) IsValid() bool {
+	switch t {
+	case TileTypeNothing:
+	case TileTypeBasic:
+	case TileTypeMagma:
+	default:
+		return false
+	}
+	return true
+}