Added FPS.

cmd/tins2020/tins2020.go

@@ -72,7 +72,10 @@ func run() error {
 
 	ctx.Init(renderer)
 
-	err = ctx.Fonts.Load("default", "fonts/OpenSans-Regular.ttf", 12)
+	err = ctx.Fonts.LoadDesc(
+		tins2020.FontDescriptor{Name: "debug", Path: "fonts/OpenSans-Regular.ttf", Size: 12},
+		tins2020.FontDescriptor{Name: "default", Path: "fonts/FiraMono-Regular.ttf", Size: 10},
+	)
 	if err != nil {
 		return err
 	}
@@ -126,8 +129,15 @@ func run() error {
 	}
 
 	game := tins2020.NewGame()
-	control := tins2020.NewTerrainRenderer(game.Terrain)
-	err = control.Init(ctx)
+
+	app := tins2020.NewContainer()
+	overlays := tins2020.NewContainer()
+	overlays.AddChild(&tins2020.FPS{})
+	content := tins2020.NewContainer()
+	app.AddChild(content)
+	app.AddChild(overlays)
+	content.AddChild(tins2020.NewTerrainRenderer(game.Terrain))
+	err = app.Init(ctx)
 	if err != nil {
 		return err
 	}
@@ -153,7 +163,7 @@ func run() error {
 					ctx.Quit()
 				}
 			}
-			control.Handle(ctx, event)
+			app.Handle(ctx, event)
 		}
 
 		if ctx.ShouldQuit {
@@ -162,7 +172,7 @@ func run() error {
 
 		renderer.SetDrawColor(0, 0, 0, 255)
 		renderer.Clear()
-		control.Render(ctx)
+		app.Render(ctx)
 		renderer.Present()
 	}
 	return nil

container.go

@@ -0,0 +1,39 @@
+package tins2020
+
+import (
+	"github.com/veandco/go-sdl2/sdl"
+)
+
+type Container struct {
+	Children []Control
+}
+
+func NewContainer() *Container {
+	return &Container{}
+}
+
+func (c *Container) AddChild(child Control) {
+	c.Children = append(c.Children, child)
+}
+
+func (c *Container) Handle(ctx *Context, event sdl.Event) {
+	for _, child := range c.Children {
+		child.Handle(ctx, event)
+	}
+}
+
+func (c *Container) Render(ctx *Context) {
+	for _, child := range c.Children {
+		child.Render(ctx)
+	}
+}
+
+func (c *Container) Init(ctx *Context) error {
+	for _, child := range c.Children {
+		err := child.Init(ctx)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}

control.go

@@ -0,0 +1,18 @@
+package tins2020
+
+import "github.com/veandco/go-sdl2/sdl"
+
+type Control interface {
+	Init(*Context) error
+	Handle(*Context, sdl.Event)
+	Render(*Context)
+}
+
+type ControlBase struct {
+}
+
+func (b *ControlBase) Handle(*Context, sdl.Event) {}
+
+func (b *ControlBase) Render(*Context) {}
+
+func (b *ControlBase) Init(*Context) error { return nil }

fonts.go

@@ -1,6 +1,8 @@
 package tins2020
 
 import (
+	"fmt"
+
 	"github.com/veandco/go-sdl2/ttf"
 	"opslag.de/schobers/fs/vfs"
 )
@@ -15,6 +17,24 @@ func (f *Fonts) Init(dir vfs.CopyDir) {
 	f.fonts = map[string]*ttf.Font{}
 }
 
+func (f *Fonts) Font(name string) *ttf.Font { return f.fonts[name] }
+
+type FontDescriptor struct {
+	Name string
+	Path string
+	Size int
+}
+
+func (f *Fonts) LoadDesc(fonts ...FontDescriptor) error {
+	for _, desc := range fonts {
+		err := f.Load(desc.Name, desc.Path, desc.Size)
+		if err != nil {
+			return fmt.Errorf("error loading '%s'; error: %v", desc.Name, err)
+		}
+	}
+	return nil
+}
+
 func (f *Fonts) Load(name, path string, size int) error {
 	fontPath, err := f.dir.Retrieve(path)
 	if err != nil {

fpsrenderer.go

@@ -0,0 +1,51 @@
+package tins2020
+
+import (
+	"fmt"
+	"time"
+
+	"github.com/veandco/go-sdl2/sdl"
+)
+
+type FPS struct {
+	ControlBase
+
+	start time.Time
+	stamp time.Duration
+	slot  int
+	ticks []int
+	total int
+}
+
+func (f *FPS) Init(*Context) error {
+	f.start = time.Now()
+	f.stamp = 0
+	f.ticks = make([]int, 51)
+	return nil
+}
+
+func (f *FPS) Render(ctx *Context) {
+	elapsed := time.Since(f.start)
+	stamp := elapsed / (20 * time.Millisecond)
+	for f.stamp < stamp {
+		f.total += f.ticks[f.slot]
+		f.slot = (f.slot + 1) % len(f.ticks)
+		f.total -= f.ticks[f.slot]
+		f.ticks[f.slot] = 0
+		f.stamp++
+	}
+	f.ticks[f.slot]++
+
+	font := ctx.Fonts.Font("debug")
+	surface, err := font.RenderUTF8Solid(fmt.Sprintf("FPS: %d", f.total), sdl.Color{R: 255, G: 255, B: 255, A: 255})
+	if err != nil {
+		return
+	}
+	defer surface.Free()
+	texture, err := NewTextureFromSurface(ctx.Renderer, surface)
+	if err != nil {
+		return
+	}
+	defer texture.Destroy()
+	texture.Copy(ctx.Renderer, texture.RectOffset(Pt(5, 5)))
+}

renderer.go

@@ -1,9 +0,0 @@
-package tins2020
-
-import "github.com/veandco/go-sdl2/sdl"
-
-type Control interface {
-	Init(*Context) error
-	Handle(*Context, sdl.Event)
-	Render(*Context)
-}

textures.go

@@ -24,6 +24,10 @@ func NewTextureFromSurface(renderer *sdl.Renderer, surface *sdl.Surface) (*Textu
 
 func (t *Texture) Rect() *sdl.Rect { return t.rect }
 
+func (t *Texture) RectOffset(offset Point) *sdl.Rect {
+	return &sdl.Rect{X: offset.X, Y: offset.Y, W: t.rect.W, H: t.rect.H}
+}
+
 func (t *Texture) Copy(renderer *sdl.Renderer, target *sdl.Rect) {
 	renderer.Copy(t.texture, t.rect, target)
 }