restorable: Refactoring: Remove Clear

Fill now fills the whole texture.

internal/buffered/image.go

@@ -187,20 +187,6 @@ func (i *Image) Fill(clr color.RGBA) {
 	i.img.Fill(clr)
 }
 
-func (i *Image) ClearFramebuffer() {
-	delayedCommandsM.Lock()
-	if needsToDelayCommands {
-		delayedCommands = append(delayedCommands, func() {
-			i.img.ClearFramebuffer()
-		})
-		delayedCommandsM.Unlock()
-		return
-	}
-	delayedCommandsM.Unlock()
-
-	i.img.ClearFramebuffer()
-}
-
 func (i *Image) ReplacePixels(pix []byte) {
 	delayedCommandsM.Lock()
 	if needsToDelayCommands {

internal/restorable/image.go

@@ -144,7 +144,7 @@ func NewImage(width, height int, volatile bool) *Image {
 		height:   height,
 		volatile: volatile,
 	}
-	i.clear()
+	fillImage(i.image, color.RGBA{})
 	theImages.add(i)
 	return i
 }
@@ -196,16 +196,11 @@ func NewScreenFramebufferImage(width, height int) *Image {
 		height: height,
 		screen: true,
 	}
-	i.clear()
+	fillImage(i.image, color.RGBA{})
 	theImages.add(i)
 	return i
 }
 
-func (i *Image) Clear() {
-	theImages.makeStaleIfDependingOn(i)
-	i.clear()
-}
-
 // quadVertices returns vertices to render a quad. These values are passed to graphicscommand.Image.
 func quadVertices(dx0, dy0, dx1, dy1, sx0, sy0, sx1, sy1, cr, cg, cb, ca float32) []float32 {
 	return []float32{
@@ -216,39 +211,6 @@ func quadVertices(dx0, dy0, dx1, dy1, sx0, sy0, sx1, sy1, cr, cg, cb, ca float32
 	}
 }
 
-// clearImage clears a graphicscommand.Image.
-// This does nothing to do with a restorable.Image's rendering state.
-func clearImage(img *graphicscommand.Image) {
-	if img == emptyImage.image {
-		panic("restorable: clearImage cannot be called on emptyImage")
-	}
-
-	// There are not 'drawTrianglesHistoryItem's for this image and emptyImage.
-	// As emptyImage is a priority image, this is restored before other regular images are restored.
-
-	// The rendering target size needs to be its 'internal' size instead of the exposed size to avoid glitches on
-	// mobile platforms (See the change 1e1f309a).
-	dw, dh := img.InternalSize()
-	sw, sh := emptyImage.image.InternalSize()
-	vs := quadVertices(0, 0, float32(dw), float32(dh), 0, 0, float32(sw), float32(sh), 0, 0, 0, 0)
-	is := graphics.QuadIndices()
-	// The first DrawTriangles must be clear mode for initialization.
-	// TODO: Can the graphicscommand package hide this knowledge?
-	img.DrawTriangles(emptyImage.image, vs, is, nil, driver.CompositeModeClear, driver.FilterNearest, driver.AddressClampToZero)
-}
-
-func (i *Image) clear() {
-	if i.priority {
-		panic("restorable: clear cannot be called on a priority image")
-	}
-
-	clearImage(i.image)
-
-	i.basePixels = Pixels{}
-	i.drawTrianglesHistory = nil
-	i.stale = false
-}
-
 // Fill fills the specified part of the image with a solid color.
 func (i *Image) Fill(clr color.RGBA) {
 	i.basePixels = Pixels{
@@ -277,7 +239,10 @@ func fillImage(i *graphicscommand.Image, clr color.RGBA) {
 
 	// TODO: Use the previous composite mode if possible.
 	compositemode := driver.CompositeModeSourceOver
-	if af < 1.0 {
+	switch {
+	case af == 0.0:
+		compositemode = driver.CompositeModeClear
+	case af < 1.0:
 		compositemode = driver.CompositeModeCopy
 	}
 
@@ -538,7 +503,7 @@ func (i *Image) restore() {
 	}
 	if i.volatile {
 		i.image = graphicscommand.NewImage(w, h)
-		i.clear()
+		fillImage(i.image, color.RGBA{})
 		return
 	}
 	if i.stale {
@@ -548,9 +513,9 @@ func (i *Image) restore() {
 	gimg := graphicscommand.NewImage(w, h)
 	// Clear the image explicitly.
 	if i != emptyImage {
-		// As clearImage uses emptyImage, clearImage cannot be called on emptyImage.
+		// As fillImage uses emptyImage, fillImage cannot be called on emptyImage.
 		// It is OK to skip this since emptyImage has its entire pixel information.
-		clearImage(gimg)
+		fillImage(gimg, color.RGBA{})
 	}
 	i.basePixels.Apply(gimg)
 

internal/shareable/image.go

@@ -344,19 +344,6 @@ func (i *Image) Fill(clr color.RGBA) {
 	delete(imagesToMakeShared, i)
 }
 
-// ClearFramebuffer clears the image with a color. This affects not only the (0, 0)-(width, height) region but also
-// the whole framebuffer region.
-func (i *Image) ClearFramebuffer() {
-	backendsM.Lock()
-	defer backendsM.Unlock()
-	if i.disposed {
-		panic("shareable: the drawing target image must not be disposed (Fill)")
-	}
-	i.ensureNotShared()
-
-	i.backend.restorable.Clear()
-}
-
 func (i *Image) ReplacePixels(p []byte) {
 	backendsM.Lock()
 	defer backendsM.Unlock()

mipmap.go

@@ -285,10 +285,6 @@ func (m *mipmap) disposeMipmaps() {
 	}
 }
 
-func (m *mipmap) clearFramebuffer() {
-	m.orig.ClearFramebuffer()
-}
-
 // mipmapLevel returns an appropriate mipmap level for the given determinant of a geometry matrix.
 //
 // mipmapLevel panics if det is NaN or 0.

uicontext.go

@@ -98,7 +98,7 @@ func (c *uiContext) Update(afterFrameUpdate func()) error {
 	}
 
 	// This clear is needed for fullscreen mode or some mobile platforms (#622).
-	c.screen.mipmap.clearFramebuffer()
+	c.screen.Clear()
 
 	op := &DrawImageOptions{}