From 9b6b5372ef1fd36f4badc0d54dd01f87206b99ce Mon Sep 17 00:00:00 2001
From: Hajime Hoshi <hajimehoshi@gmail.com>
Date: Wed, 27 Jul 2016 12:24:30 +0900
Subject: [PATCH] pixels: Remove image member

---
 imageimpl.go              | 13 +++++--------
 internal/pixels/pixels.go | 21 ++++++---------------
 2 files changed, 11 insertions(+), 23 deletions(-)

diff --git a/imageimpl.go b/imageimpl.go
index 4a3baf220..257e8b30a 100644
--- a/imageimpl.go
+++ b/imageimpl.go
@@ -34,7 +34,7 @@ type imageImpl struct {
 	width    int
 	height   int
 	filter   Filter
-	pixels   *pixels.Pixels
+	pixels   pixels.Pixels
 	volatile bool
 	screen   bool
 	m        sync.Mutex
@@ -51,7 +51,6 @@ func newImageImpl(width, height int, filter Filter, volatile bool) (*imageImpl,
 		height:   height,
 		filter:   filter,
 		volatile: volatile,
-		pixels:   pixels.NewPixels(img),
 	}
 	runtime.SetFinalizer(i, (*imageImpl).Dispose)
 	return i, nil
@@ -83,7 +82,6 @@ func newImageImplFromImage(source image.Image, filter Filter) (*imageImpl, error
 		width:  w,
 		height: h,
 		filter: filter,
-		pixels: pixels.NewPixels(img),
 	}
 	i.pixels.ReplacePixels(p)
 	runtime.SetFinalizer(i, (*imageImpl).Dispose)
@@ -101,7 +99,6 @@ func newScreenImageImpl(width, height int) (*imageImpl, error) {
 		height:   height,
 		volatile: true,
 		screen:   true,
-		pixels:   pixels.NewPixels(img),
 	}
 	runtime.SetFinalizer(i, (*imageImpl).Dispose)
 	return i, nil
@@ -181,7 +178,7 @@ func (i *imageImpl) At(x, y int, context *opengl.Context) color.Color {
 		return color.Transparent
 	}
 	idx := 4*x + 4*y*i.width
-	clr, err := i.pixels.At(idx, context)
+	clr, err := i.pixels.At(idx, i.image, context)
 	if err != nil {
 		panic(err)
 	}
@@ -197,7 +194,7 @@ func (i *imageImpl) ensurePixels(context *opengl.Context) error {
 	if i.volatile {
 		return nil
 	}
-	if err := i.pixels.ReadPixelsFromVRAMIfStale(context); err != nil {
+	if err := i.pixels.ReadPixelsFromVRAMIfStale(i.image, context); err != nil {
 		return err
 	}
 	return nil
@@ -225,7 +222,7 @@ func (i *imageImpl) resetPixelsIfDependingOn(target *imageImpl, context *opengl.
 		i.pixels.MakeStale()
 		return nil
 	}
-	if err := i.pixels.ReadPixelsFromVRAM(context); err != nil {
+	if err := i.pixels.ReadPixelsFromVRAM(i.image, context); err != nil {
 		return err
 	}
 	return nil
@@ -282,7 +279,7 @@ func (i *imageImpl) Dispose() error {
 	}
 	i.image = nil
 	i.disposed = true
-	i.pixels = nil
+	i.pixels.Clear()
 	runtime.SetFinalizer(i, nil)
 	return nil
 }
diff --git a/internal/pixels/pixels.go b/internal/pixels/pixels.go
index 0c71729cc..c1189786d 100644
--- a/internal/pixels/pixels.go
+++ b/internal/pixels/pixels.go
@@ -33,8 +33,6 @@ type drawImageHistoryItem struct {
 
 // Pixels represents pixels of an image for restoring when GL context is lost.
 type Pixels struct {
-	image *graphics.Image
-
 	// basePixels and baseColor are exclusive.
 	basePixels       []uint8
 	baseColor        color.Color
@@ -42,12 +40,6 @@ type Pixels struct {
 	stale            bool
 }
 
-func NewPixels(image *graphics.Image) *Pixels {
-	return &Pixels{
-		image: image,
-	}
-}
-
 func (p *Pixels) MakeStale() {
 	p.basePixels = nil
 	p.baseColor = nil
@@ -97,9 +89,9 @@ func (p *Pixels) AppendDrawImageHistory(image *graphics.Image, vertices []int16,
 //
 // Note that this must not be called until context is available.
 // This means Pixels members must match with acutal state in VRAM.
-func (p *Pixels) At(idx int, context *opengl.Context) (color.Color, error) {
+func (p *Pixels) At(idx int, image *graphics.Image, context *opengl.Context) (color.Color, error) {
 	if p.basePixels == nil || p.drawImageHistory != nil || p.stale {
-		if err := p.ReadPixelsFromVRAM(context); err != nil {
+		if err := p.ReadPixelsFromVRAM(image, context); err != nil {
 			return nil, err
 		}
 	}
@@ -119,9 +111,9 @@ func (p *Pixels) DependsOn(target *graphics.Image) bool {
 	return false
 }
 
-func (p *Pixels) ReadPixelsFromVRAM(context *opengl.Context) error {
+func (p *Pixels) ReadPixelsFromVRAM(image *graphics.Image, context *opengl.Context) error {
 	var err error
-	p.basePixels, err = p.image.Pixels(context)
+	p.basePixels, err = image.Pixels(context)
 	if err != nil {
 		return err
 	}
@@ -131,11 +123,11 @@ func (p *Pixels) ReadPixelsFromVRAM(context *opengl.Context) error {
 	return nil
 }
 
-func (p *Pixels) ReadPixelsFromVRAMIfStale(context *opengl.Context) error {
+func (p *Pixels) ReadPixelsFromVRAMIfStale(image *graphics.Image, context *opengl.Context) error {
 	if !p.stale {
 		return nil
 	}
-	return p.ReadPixelsFromVRAM(context)
+	return p.ReadPixelsFromVRAM(image, context)
 }
 
 func (p *Pixels) HasDependency() bool {
@@ -177,7 +169,6 @@ func (p *Pixels) CreateImage(context *opengl.Context, width, height int, filter
 			return nil, err
 		}
 	}
-	p.image = gimg
 	p.basePixels, err = gimg.Pixels(context)
 	if err != nil {
 		return nil, err