Added Resources abstraction.

addons/fs/afero.go

@@ -0,0 +1,76 @@
+package fs
+
+import (
+	"io"
+	"os"
+	"path/filepath"
+
+	"github.com/spf13/afero"
+	"opslag.de/schobers/zntg"
+	"opslag.de/schobers/zntg/ui"
+)
+
+type aferoResources struct {
+	dir  string
+	fs   afero.Fs
+	copy *zntg.Dir
+}
+
+var _ ui.Resources = &aferoResources{}
+
+// NewAferoResources provides resources from a afero file system. The prefix is used as a prefix of the temporary directory.
+func NewAferoResources(fs afero.Fs, prefix string) (ui.Resources, error) {
+	return NewAferoFallbackResources("", fs, prefix)
+}
+
+// NewAferoFallbackResources provides resources from the directory first and uses afero file system as a fallback if the resource in the directory doesn't exist. The prefix is used as a prefix of the temporary directory.
+func NewAferoFallbackResources(dir string, fs afero.Fs, prefix string) (ui.Resources, error) {
+	copy, err := zntg.NewTempDir(prefix)
+	if err != nil {
+		return nil, err
+	}
+	return &aferoResources{dir, fs, copy}, nil
+}
+
+func (r *aferoResources) fetchAferoResource(name string) (string, error) {
+	path := r.copy.FilePath(name)
+	if !zntg.FileExists(path) {
+		src, err := r.fs.Open(name)
+		if err != nil {
+			return "", err
+		}
+		defer src.Close()
+
+		err = r.copy.Write(name, src)
+		if err != nil {
+			return "", err
+		}
+	}
+	return path, nil
+}
+
+func (r *aferoResources) openAferoResource(name string) (io.ReadCloser, error) { return r.fs.Open(name) }
+
+func (r *aferoResources) Destroy() error { return r.copy.Destroy() }
+
+func (r *aferoResources) FetchResource(name string) (string, error) {
+	if r.dir == "" {
+		return r.fetchAferoResource(name)
+	}
+	path := filepath.Join(r.dir, name)
+	if zntg.FileExists(path) {
+		return path, nil
+	}
+	return r.fetchAferoResource(name)
+}
+
+func (r *aferoResources) OpenResource(name string) (io.ReadCloser, error) {
+	if r.dir == "" {
+		return r.openAferoResource(name)
+	}
+	path := filepath.Join(r.dir, name)
+	if zntg.FileExists(path) {
+		return os.Open(path)
+	}
+	return r.openAferoResource(name)
+}

allg5ui/renderer.go

@@ -47,7 +47,7 @@ func NewRenderer(w, h int, opts allg5.NewDisplayOptions) (*Renderer, error) {
 	})
 	clean = nil
 
-	return &Renderer{disp, eq, nil, map[string]*font{}, user, ui.KeyState{}, ui.KeyModifierNone, ui.MouseCursorDefault}, nil
+	return &Renderer{disp, eq, nil, map[string]*font{}, user, &ui.OSResources{}, ui.KeyState{}, ui.KeyModifierNone, ui.MouseCursorDefault}, nil
 }
 
 // Renderer implements ui.Renderer using Allegro 5.
@@ -57,6 +57,7 @@ type Renderer struct {
 	unh  func(allg5.Event)
 	ft   map[string]*font
 	user *allg5.UserEventSource
+	res  ui.Resources
 
 	keys      ui.KeyState
 	modifiers ui.KeyModifier
@@ -153,6 +154,7 @@ func (r *Renderer) Destroy() error {
 	}
 	r.ft = nil
 	r.disp.Destroy()
+	r.res.Destroy()
 	return nil
 }
 
@@ -182,10 +184,14 @@ func (r *Renderer) CreateTexture(source ui.ImageSource) (ui.Texture, error) {
 }
 
 func (r *Renderer) CreateTextureGo(im image.Image, source bool) (ui.Texture, error) {
-	return r.createTexture(ui.ImageGoSource{im}, true)
+	return r.createTexture(ui.ImageSourceGo{im}, true)
 }
 
 func (r *Renderer) CreateTexturePath(path string, source bool) (ui.Texture, error) {
+	path, err := r.res.FetchResource(path)
+	if err != nil {
+		return nil, err
+	}
 	bmp, err := allg5.LoadBitmap(path)
 	if err != nil {
 		return nil, err
@@ -250,7 +256,11 @@ func (r *Renderer) Rectangle(rect geom.RectangleF32, c color.Color, thickness fl
 }
 
 func (r *Renderer) RegisterFont(name, path string, size int) error {
-	var f, err = allg5.LoadTTFFont(path, size)
+	path, err := r.res.FetchResource(path)
+	if err != nil {
+		return err
+	}
+	font, err := allg5.LoadTTFFont(path, size)
 	if err != nil {
 		return err
 	}
@@ -258,7 +268,7 @@ func (r *Renderer) RegisterFont(name, path string, size int) error {
 	if prev != nil {
 		prev.Destroy()
 	}
-	r.ft[name] = newFont(f)
+	r.ft[name] = newFont(font)
 	return nil
 }
 
@@ -281,6 +291,8 @@ func (r *Renderer) RenderToDisplay() {
 	r.disp.SetAsTarget()
 }
 
+func (r *Renderer) Resources() ui.Resources { return r.res }
+
 func (r *Renderer) Size() geom.PointF32 {
 	return geom.PtF32(float32(r.disp.Width()), float32(r.disp.Height()))
 }
@@ -294,6 +306,13 @@ func (r *Renderer) SetMouseCursor(c ui.MouseCursor) {
 	r.cursor = c
 }
 
+func (r *Renderer) SetResourceProvider(factory func() ui.Resources) {
+	if r.res != nil {
+		r.res.Destroy()
+	}
+	r.res = factory()
+}
+
 func (r *Renderer) SetUnhandledEventHandler(handler func(allg5.Event)) {
 	r.unh = handler
 }

io.go

@@ -7,6 +7,7 @@ import (
 	_ "image/jpeg" // decoding of JPEG
 	"image/png"
 	"io"
+	"io/ioutil"
 	"os"
 	"path/filepath"
 )
@@ -47,6 +48,29 @@ func DecodeJSON(path string, value interface{}) error {
 	return err
 }
 
+// Dir is a convenience struct for representing a path to a directory.
+type Dir struct {
+	Path string
+}
+
+// FilePath returns the path of a file with the specified name in the directory.
+func (d *Dir) FilePath(name string) string {
+	return filepath.Join(d.Path, name)
+}
+
+// Write writes the content of the reader into a file with the specified name.
+func (d *Dir) Write(name string, r io.Reader) error {
+	path := d.FilePath(name)
+	dir := filepath.Dir(path)
+	os.MkdirAll(dir, 0777)
+	return EncodeFile(path, r, CopyReader)
+}
+
+// Destroy removes the directory.
+func (d *Dir) Destroy() error {
+	return os.RemoveAll(d.Path)
+}
+
 // EncoderFn describes a generic encoder.
 type EncoderFn func(io.Writer, interface{}) error
 
@@ -70,6 +94,14 @@ func EncodePNG(path string, im image.Image) error {
 	return EncodeFile(path, im, PNGEncoder)
 }
 
+// FileExists returns if file exists on specified path.
+func FileExists(path string) bool {
+	if _, err := os.Stat(path); os.IsNotExist(err) {
+		return false
+	}
+	return true
+}
+
 var _ DecoderFn = ImageDecoder
 
 // ImageDecoder is a generic image decoder.
@@ -91,6 +123,15 @@ var _ EncoderFn = PNGEncoder
 // PNGEncoder is a generic PNG encoder.
 func PNGEncoder(w io.Writer, value interface{}) error { return png.Encode(w, value.(image.Image)) }
 
+// NewTempDir creates a temporary directory.
+func NewTempDir(prefix string) (*Dir, error) {
+	path, err := ioutil.TempDir("", prefix)
+	if nil != err {
+		return nil, err
+	}
+	return &Dir{path}, nil
+}
+
 // UserDir gives back the user configuration directory with given name.
 func UserDir(name string) (string, error) {
 	config, err := os.UserConfigDir()
@@ -113,3 +154,11 @@ func UserFile(app, name string) (string, error) {
 	}
 	return filepath.Join(dir, name), nil
 }
+
+var _ EncoderFn = CopyReader
+
+// CopyReader copies the provided value to the output.
+func CopyReader(w io.Writer, value interface{}) error {
+	_, err := io.Copy(w, value.(io.Reader))
+	return err
+}

sdlui/renderer.go

@@ -23,6 +23,7 @@ type Renderer struct {
 	renderer  *sdl.Renderer
 	refresh   uint32
 	fonts     map[string]*Font
+	resources ui.Resources
 
 	mouse   geom.PointF32
 	cursor  ui.MouseCursor
@@ -88,6 +89,7 @@ func NewRenderer(title string, width, height int32, opts NewRendererOptions) (*R
 		renderer:  renderer,
 		refresh:   refresh,
 		fonts:     map[string]*Font{},
+		resources: &ui.OSResources{},
 		cursors:   map[sdl.SystemCursor]*sdl.Cursor{},
 	}, nil
 }
@@ -210,6 +212,7 @@ func (r *Renderer) Destroy() error {
 	r.window.Destroy()
 	ttf.Quit()
 	sdl.Quit()
+	r.resources.Destroy()
 	return nil
 }
 
@@ -253,11 +256,11 @@ func (r *Renderer) CreateTexture(source ui.ImageSource) (ui.Texture, error) {
 }
 
 func (r *Renderer) CreateTextureGo(m image.Image, source bool) (ui.Texture, error) {
-	return r.createTexture(ui.ImageGoSource{Image: m}, source)
+	return r.createTexture(ui.ImageSourceGo{Image: m}, source)
 }
 
 func (r *Renderer) CreateTexturePath(path string, source bool) (ui.Texture, error) {
-	return r.createTexture(ui.ImageFileSource(path), source)
+	return r.createTexture(ui.ImageSourceResource{Resources: r.resources, Name: path}, source)
 }
 
 func (r *Renderer) CreateTextureTarget(w, h float32) (ui.Texture, error) {
@@ -331,6 +334,10 @@ func (r *Renderer) Rectangle(rect geom.RectangleF32, c color.Color, thickness fl
 }
 
 func (r *Renderer) RegisterFont(name, path string, size int) error {
+	path, err := r.resources.FetchResource(path)
+	if err != nil {
+		return err
+	}
 	font, err := ttf.OpenFont(path, size)
 	if err != nil {
 		return err
@@ -420,6 +427,17 @@ func (r *Renderer) TextAlign(p geom.PointF32, font string, color color.Color, te
 	}
 }
 
+// Resources
+
+func (r *Renderer) Resources() ui.Resources { return r.resources }
+
+func (r *Renderer) SetResourceProvider(factory func() ui.Resources) {
+	if r.resources != nil {
+		r.resources.Destroy()
+	}
+	r.resources = factory()
+}
+
 // Texture
 
 func (r *Renderer) Image() image.Image { return nil }

ui/context.go

@@ -3,10 +3,10 @@ package ui
 type Context interface {
 	Animate()
 	HasQuit() bool
-	Textures() *Textures
 	Quit()
 	Renderer() Renderer
 	Style() *Style
+	Textures() *Textures
 }
 
 var _ Context = &context{}
@@ -32,7 +32,9 @@ func (c *context) HasQuit() bool {
 	}
 }
 
-func (c *context) Textures() *Textures { return c.textures }
+func (c *context) Renderer() Renderer { return c.r }
+
+func (c *context) Style() *Style { return c.style }
 
 func (c *context) Quit() {
 	if !c.HasQuit() {
@@ -40,9 +42,7 @@ func (c *context) Quit() {
 	}
 }
 
-func (c *context) Renderer() Renderer { return c.r }
+func (c *context) Textures() *Textures { return c.textures }
-
-func (c *context) Style() *Style { return c.style }
 
 // Handle implement EventTarget
 

ui/copyresources.go

@@ -0,0 +1,56 @@
+package ui
+
+import (
+	"io"
+	"os"
+
+	"opslag.de/schobers/zntg"
+)
+
+var _ Resources = &CopyResources{}
+
+// CopyResources copies and opens resources to a temporary directory.
+type CopyResources struct {
+	Source Resources
+
+	copy *zntg.Dir
+}
+
+// NewCopyResource creates a proxy that copied resources first to disk.
+func NewCopyResource(prefix string, source Resources) (*CopyResources, error) {
+	copy, err := zntg.NewTempDir(prefix)
+	if nil != err {
+		return nil, err
+	}
+	return &CopyResources{source, copy}, nil
+}
+
+// FetchResource copies the file from the source to disk and returns the path to it.
+func (r *CopyResources) FetchResource(name string) (string, error) {
+	path := r.copy.FilePath(name)
+	if !zntg.FileExists(path) {
+		src, err := r.Source.OpenResource(name)
+		if err != nil {
+			return "", err
+		}
+		defer src.Close()
+
+		err = r.copy.Write(name, src)
+		if nil != err {
+			return "", err
+		}
+	}
+	return path, nil
+}
+
+// OpenResource opens the (copied) resource on disk.
+func (r *CopyResources) OpenResource(name string) (io.ReadCloser, error) {
+	path := r.copy.FilePath(name)
+	src, err := os.Open(path)
+	return src, err
+}
+
+// Destroy destroy the copy of the resources.
+func (r *CopyResources) Destroy() error {
+	return r.copy.Destroy()
+}

ui/imagesource.go

@@ -2,36 +2,46 @@ package ui
 
 import (
 	"image"
-	"os"
+
+	"opslag.de/schobers/zntg"
 )
 
 type ImageSource interface {
 	CreateImage() (image.Image, error)
 }
 
-type ImageFileSource string
+type ImageSourceFile string
 
-var _ ImageSource = ImageFileSource("")
+var _ ImageSource = ImageSourceFile("")
 
-func (s ImageFileSource) CreateImage() (image.Image, error) {
+func (s ImageSourceFile) CreateImage() (image.Image, error) {
-	f, err := os.Open(string(s))
+	return zntg.DecodeImage(string(s))
-	if err != nil {
-		return nil, err
-	}
-	defer f.Close()
-	m, _, err := image.Decode(f)
-	if err != nil {
-		return nil, err
-	}
-	return m, nil
 }
 
-type ImageGoSource struct {
+type ImageSourceGo struct {
 	image.Image
 }
 
-var _ ImageSource = ImageGoSource{}
+var _ ImageSource = ImageSourceGo{}
 
-func (s ImageGoSource) CreateImage() (image.Image, error) {
+func (s ImageSourceGo) CreateImage() (image.Image, error) {
 	return s.Image, nil
 }
+
+type ImageSourceResource struct {
+	Resources Resources
+	Name      string
+}
+
+func (s ImageSourceResource) CreateImage() (image.Image, error) {
+	src, err := s.Resources.OpenResource(s.Name)
+	if err != nil {
+		return nil, err
+	}
+	defer src.Close()
+	value, err := zntg.ImageDecoder(src)
+	if err != nil {
+		return nil, err
+	}
+	return value.(image.Image), nil
+}

ui/osresources.go

@@ -0,0 +1,34 @@
+package ui
+
+import (
+	"io"
+	"os"
+)
+
+var _ Resources = &OSResources{}
+
+// DefaultResources returns the default Resources implementation (OSResources).
+func DefaultResources() Resources {
+	return &OSResources{}
+}
+
+// OSResources is Resources implementation that uses the default file system directly.
+type OSResources struct {
+}
+
+// FetchResource checks if file is available and returns the specified path.
+func (r *OSResources) FetchResource(name string) (string, error) {
+	_, err := os.Stat(name)
+	if err != nil {
+		return "", err
+	}
+	return name, nil
+}
+
+// OpenResource opens the specified file on disk.
+func (r *OSResources) OpenResource(name string) (io.ReadCloser, error) {
+	return os.Open(name)
+}
+
+// Destroy does nothing.
+func (r *OSResources) Destroy() error { return nil }

ui/renderer.go

@@ -35,4 +35,8 @@ type Renderer interface {
 	Target() Texture
 	Text(p geom.PointF32, font string, color color.Color, text string)
 	TextAlign(p geom.PointF32, font string, color color.Color, text string, align HorizontalAlignment)
+
+	// Resources
+	Resources() Resources
+	SetResourceProvider(factory func() Resources)
 }

ui/resources.go

@@ -0,0 +1,13 @@
+package ui
+
+import "io"
+
+// Resources is an abstraction on resources.
+type Resources interface {
+	// FetchResource should fetch the resource with the specified name and return a path (on disk) where the resource can be accessed.
+	FetchResource(name string) (string, error)
+	// OpenResource should open the resource with the specified name. The user is responsible for closing the resource.
+	OpenResource(name string) (io.ReadCloser, error)
+	// Destroy can be used for cleaning up at the end of the applications lifetime.
+	Destroy() error
+}