internal/buffered: separate ReplacePixels with the large-area and small-area versions

For the large-area version, this doesn't require a graphics driver.
This is necessary to ensure that ReplacePixels never needs a graphics
driver.

image.go

@@ -764,7 +764,7 @@ func (i *Image) Set(x, y int, clr color.Color) {
 
 	r, g, b, a := clr.RGBA()
 	pix := []byte{byte(r >> 8), byte(g >> 8), byte(b >> 8), byte(a >> 8)}
-	if err := i.image.ReplacePixels(pix, x, y, 1, 1); err != nil {
+	if err := i.image.ReplaceSmallAreaPixels(pix, x, y, 1, 1); err != nil {
 		ui.SetError(err)
 	}
 }
@@ -816,7 +816,7 @@ func (i *Image) ReplacePixels(pixels []byte) {
 	// Do not need to copy pixels here.
 	// * In internal/mipmap, pixels are copied when necessary.
 	// * In internal/shareable, pixels are copied to make its paddings.
-	if err := i.image.ReplacePixels(pixels, r.Min.X, r.Min.Y, r.Dx(), r.Dy()); err != nil {
+	if err := i.image.ReplaceLargeAreaPixels(pixels, r.Min.X, r.Min.Y, r.Dx(), r.Dy()); err != nil {
 		ui.SetError(err)
 	}
 }

image_test.go

@@ -1882,6 +1882,18 @@ func TestImageReplacePixelsOnSubImage(t *testing.T) {
 	r1 := image.Rect(11, 10, 16, 13)
 	dst.SubImage(r1).(*ebiten.Image).ReplacePixels(pix1)
 
+	// Clear the pixels. This should not affect the result.
+	idx = 0
+	for j := 0; j < 3; j++ {
+		for i := 0; i < 5; i++ {
+			pix1[4*idx] = 0
+			pix1[4*idx+1] = 0
+			pix1[4*idx+2] = 0
+			pix1[4*idx+3] = 0
+			idx++
+		}
+	}
+
 	for j := 0; j < 31; j++ {
 		for i := 0; i < 17; i++ {
 			got := dst.At(i, j).(color.RGBA)

internal/atlas/image.go

@@ -337,7 +337,7 @@ func (i *Image) putOnAtlas(graphicsDriver graphicsdriver.Graphics) error {
 				pixels[4*(i.width*y+x)+3] = a
 			}
 		}
-		newI.replacePixels(pixels)
+		newI.replacePixels(pixels, 0, 0, i.width, i.height)
 	} else {
 		// If the underlying graphics driver doesn't require restoring from the context lost, just a regular
 		// rendering works.
@@ -538,13 +538,13 @@ func (i *Image) drawTriangles(srcs [graphics.ShaderImageNum]*Image, vertices []f
 	}
 }
 
-func (i *Image) ReplacePixels(pix []byte) {
+func (i *Image) ReplacePixels(pix []byte, x, y, width, height int) {
 	backendsM.Lock()
 	defer backendsM.Unlock()
-	i.replacePixels(pix)
+	i.replacePixels(pix, x, y, width, height)
 }
 
-func (i *Image) replacePixels(pix []byte) {
+func (i *Image) replacePixels(pix []byte, x, y, width, height int) {
 	if i.disposed {
 		panic("atlas: the image must not be disposed at replacePixels")
 	}
@@ -558,25 +558,37 @@ func (i *Image) replacePixels(pix []byte) {
 		i.allocate(true)
 	}
 
-	x, y, w, h := i.regionWithPadding()
-	if pix == nil {
-		i.backend.restorable.ReplacePixels(nil, x, y, w, h)
+	// If the replacing area is small, replace the pixels without the padding.
+	if x != 0 || y != 0 || width != i.width || height != i.height {
+		ox, oy, _, _ := i.regionWithPadding()
+		x += ox + paddingSize
+		y += oy + paddingSize
+		copied := make([]byte, len(pix))
+		copy(copied, pix)
+		i.backend.restorable.ReplacePixels(copied, x, y, width, height)
 		return
 	}
 
-	ow, oh := w-2*paddingSize, h-2*paddingSize
+	// If the whole area is being replaced, add the padding.
+	px, py, pw, ph := i.regionWithPadding()
+	if pix == nil {
+		i.backend.restorable.ReplacePixels(nil, px, py, pw, ph)
+		return
+	}
+
+	ow, oh := pw-2*paddingSize, ph-2*paddingSize
 	if l := 4 * ow * oh; len(pix) != l {
 		panic(fmt.Sprintf("atlas: len(p) must be %d but %d", l, len(pix)))
 	}
 
-	pixb := theTemporaryPixels.alloc(4 * w * h)
+	pixb := theTemporaryPixels.alloc(4 * pw * ph)
 
 	// Clear the edges. pixb might not be zero-cleared.
-	rowPixels := 4 * w
+	rowPixels := 4 * pw
 	for i := 0; i < rowPixels; i++ {
 		pixb[i] = 0
 	}
-	for j := 1; j < h-1; j++ {
+	for j := 1; j < ph-1; j++ {
 		pixb[rowPixels*j] = 0
 		pixb[rowPixels*j+1] = 0
 		pixb[rowPixels*j+2] = 0
@@ -587,15 +599,15 @@ func (i *Image) replacePixels(pix []byte) {
 		pixb[rowPixels*(j+1)-1] = 0
 	}
 	for i := 0; i < rowPixels; i++ {
-		pixb[rowPixels*(h-1)+i] = 0
+		pixb[rowPixels*(ph-1)+i] = 0
 	}
 
 	// Copy the content.
 	for j := 0; j < oh; j++ {
-		copy(pixb[4*((j+paddingSize)*w+paddingSize):], pix[4*j*ow:4*(j+1)*ow])
+		copy(pixb[4*((j+paddingSize)*pw+paddingSize):], pix[4*j*ow:4*(j+1)*ow])
 	}
 
-	i.backend.restorable.ReplacePixels(pixb, x, y, w, h)
+	i.backend.restorable.ReplacePixels(pixb, px, py, pw, ph)
 }
 
 func (img *Image) Pixels(graphicsDriver graphicsdriver.Graphics, x, y, width, height int) ([]byte, error) {

internal/atlas/image_test.go

@@ -63,17 +63,17 @@ func TestEnsureIsolated(t *testing.T) {
 	img1 := atlas.NewImage(bigSize, 100)
 	defer img1.MarkDisposed()
 	// Ensure img1's region is allocated.
-	img1.ReplacePixels(make([]byte, 4*bigSize*100))
+	img1.ReplacePixels(make([]byte, 4*bigSize*100), 0, 0, bigSize, 100)
 
 	img2 := atlas.NewImage(100, bigSize)
 	defer img2.MarkDisposed()
-	img2.ReplacePixels(make([]byte, 4*100*bigSize))
+	img2.ReplacePixels(make([]byte, 4*100*bigSize), 0, 0, 100, bigSize)
 
 	const size = 32
 
 	img3 := atlas.NewImage(size/2, size/2)
 	defer img3.MarkDisposed()
-	img3.ReplacePixels(make([]byte, (size/2)*(size/2)*4))
+	img3.ReplacePixels(make([]byte, (size/2)*(size/2)*4), 0, 0, size/2, size/2)
 
 	img4 := atlas.NewImage(size, size)
 	defer img4.MarkDisposed()
@@ -87,7 +87,7 @@ func TestEnsureIsolated(t *testing.T) {
 			pix[4*(i+j*size)+3] = byte(i + j)
 		}
 	}
-	img4.ReplacePixels(pix)
+	img4.ReplacePixels(pix, 0, 0, size, size)
 
 	const (
 		dx0 = size / 4
@@ -142,11 +142,11 @@ func TestReputOnAtlas(t *testing.T) {
 
 	img0 := atlas.NewImage(size, size)
 	defer img0.MarkDisposed()
-	img0.ReplacePixels(make([]byte, 4*size*size))
+	img0.ReplacePixels(make([]byte, 4*size*size), 0, 0, size, size)
 
 	img1 := atlas.NewImage(size, size)
 	defer img1.MarkDisposed()
-	img1.ReplacePixels(make([]byte, 4*size*size))
+	img1.ReplacePixels(make([]byte, 4*size*size), 0, 0, size, size)
 	if got, want := img1.IsOnAtlasForTesting(), true; got != want {
 		t.Errorf("got: %v, want: %v", got, want)
 	}
@@ -162,12 +162,12 @@ func TestReputOnAtlas(t *testing.T) {
 			pix[4*(i+j*size)+3] = byte(i + j)
 		}
 	}
-	img2.ReplacePixels(pix)
+	img2.ReplacePixels(pix, 0, 0, size, size)
 
 	img3 := atlas.NewImage(size, size)
 	img3.SetVolatile(true)
 	defer img3.MarkDisposed()
-	img1.ReplacePixels(make([]byte, 4*size*size))
+	img1.ReplacePixels(make([]byte, 4*size*size), 0, 0, size, size)
 	if got, want := img3.IsOnAtlasForTesting(), false; got != want {
 		t.Errorf("got: %v, want: %v", got, want)
 	}
@@ -256,7 +256,7 @@ func TestReputOnAtlas(t *testing.T) {
 		if err := atlas.PutImagesOnAtlasForTesting(ui.GraphicsDriverForTesting()); err != nil {
 			t.Fatal(err)
 		}
-		img1.ReplacePixels(make([]byte, 4*size*size))
+		img1.ReplacePixels(make([]byte, 4*size*size), 0, 0, size, size)
 		img0.DrawTriangles([graphics.ShaderImageNum]*atlas.Image{img1}, vs, is, affine.ColorMIdentity{}, graphicsdriver.CompositeModeCopy, graphicsdriver.FilterNearest, graphicsdriver.AddressUnsafe, dr, graphicsdriver.Region{}, [graphics.ShaderImageNum - 1][2]float32{}, nil, nil, false)
 		if got, want := img1.IsOnAtlasForTesting(), false; got != want {
 			t.Errorf("got: %v, want: %v", got, want)
@@ -298,7 +298,7 @@ func TestExtend(t *testing.T) {
 		p0[4*i+2] = byte(i)
 		p0[4*i+3] = byte(i)
 	}
-	img0.ReplacePixels(p0)
+	img0.ReplacePixels(p0, 0, 0, w0, h0)
 
 	const w1, h1 = minImageSizeForTesting + 1, 100
 	img1 := atlas.NewImage(w1, h1)
@@ -312,7 +312,7 @@ func TestExtend(t *testing.T) {
 		p1[4*i+3] = byte(i)
 	}
 	// Ensure to allocate
-	img1.ReplacePixels(p1)
+	img1.ReplacePixels(p1, 0, 0, w1, h1)
 
 	pix0, err := img0.Pixels(ui.GraphicsDriverForTesting(), 0, 0, w0, h0)
 	if err != nil {
@@ -367,7 +367,7 @@ func TestReplacePixelsAfterDrawTriangles(t *testing.T) {
 		pix[4*i+2] = byte(i)
 		pix[4*i+3] = byte(i)
 	}
-	src.ReplacePixels(pix)
+	src.ReplacePixels(pix, 0, 0, w, h)
 
 	vs := quadVertices(w, h, 0, 0, 1)
 	is := graphics.QuadIndices()
@@ -378,7 +378,7 @@ func TestReplacePixelsAfterDrawTriangles(t *testing.T) {
 		Height: h,
 	}
 	dst.DrawTriangles([graphics.ShaderImageNum]*atlas.Image{src}, vs, is, affine.ColorMIdentity{}, graphicsdriver.CompositeModeCopy, graphicsdriver.FilterNearest, graphicsdriver.AddressUnsafe, dr, graphicsdriver.Region{}, [graphics.ShaderImageNum - 1][2]float32{}, nil, nil, false)
-	dst.ReplacePixels(pix)
+	dst.ReplacePixels(pix, 0, 0, w, h)
 
 	pix, err := dst.Pixels(ui.GraphicsDriverForTesting(), 0, 0, w, h)
 	if err != nil {
@@ -415,7 +415,7 @@ func TestSmallImages(t *testing.T) {
 		pix[4*i+2] = 0xff
 		pix[4*i+3] = 0xff
 	}
-	src.ReplacePixels(pix)
+	src.ReplacePixels(pix, 0, 0, w, h)
 
 	vs := quadVertices(w, h, 0, 0, 1)
 	is := graphics.QuadIndices()
@@ -462,7 +462,7 @@ func TestLongImages(t *testing.T) {
 		pix[4*i+2] = 0xff
 		pix[4*i+3] = 0xff
 	}
-	src.ReplacePixels(pix)
+	src.ReplacePixels(pix, 0, 0, w, h)
 
 	const scale = 120
 	vs := quadVertices(w, h, 0, 0, scale)
@@ -512,12 +512,12 @@ func TestExtendWithBigImage(t *testing.T) {
 	img0 := atlas.NewImage(1, 1)
 	defer img0.MarkDisposed()
 
-	img0.ReplacePixels(make([]byte, 4*1*1))
+	img0.ReplacePixels(make([]byte, 4*1*1), 0, 0, 1, 1)
 
 	img1 := atlas.NewImage(minImageSizeForTesting+1, minImageSizeForTesting+1)
 	defer img1.MarkDisposed()
 
-	img1.ReplacePixels(make([]byte, 4*(minImageSizeForTesting+1)*(minImageSizeForTesting+1)))
+	img1.ReplacePixels(make([]byte, 4*(minImageSizeForTesting+1)*(minImageSizeForTesting+1)), 0, 0, minImageSizeForTesting+1, minImageSizeForTesting+1)
 }
 
 // Issue #1217
@@ -526,7 +526,7 @@ func TestMaxImageSize(t *testing.T) {
 	s := maxImageSizeForTesting - 2*atlas.PaddingSize
 	img := atlas.NewImage(s, s)
 	defer img.MarkDisposed()
-	img.ReplacePixels(make([]byte, 4*s*s))
+	img.ReplacePixels(make([]byte, 4*s*s), 0, 0, s, s)
 }
 
 // Issue #1217 (disabled)
@@ -539,7 +539,7 @@ func Disable_TestMinImageSize(t *testing.T) {
 	s := minImageSizeForTesting
 	img := atlas.NewImage(s, s)
 	defer img.MarkDisposed()
-	img.ReplacePixels(make([]byte, 4*s*s))
+	img.ReplacePixels(make([]byte, 4*s*s), 0, 0, s, s)
 }
 
 // Issue #1421

internal/atlas/shader_test.go

@@ -65,9 +65,9 @@ func TestImageDrawTwice(t *testing.T) {
 
 	dst := atlas.NewImage(w, h)
 	src0 := atlas.NewImage(w, h)
-	src0.ReplacePixels([]byte{0xff, 0xff, 0xff, 0xff})
+	src0.ReplacePixels([]byte{0xff, 0xff, 0xff, 0xff}, 0, 0, w, h)
 	src1 := atlas.NewImage(w, h)
-	src1.ReplacePixels([]byte{0x80, 0x80, 0x80, 0xff})
+	src1.ReplacePixels([]byte{0x80, 0x80, 0x80, 0xff}, 0, 0, w, h)
 
 	vs := quadVertices(w, h, 0, 0, 1)
 	is := graphics.QuadIndices()

internal/buffered/image.go

@@ -117,7 +117,7 @@ func (i *Image) invalidatePendingPixels() {
 
 func (i *Image) resolvePendingPixels(keepPendingPixels bool) {
 	if i.needsToResolvePixels {
-		i.img.ReplacePixels(i.pixels)
+		i.img.ReplacePixels(i.pixels, 0, 0, i.width, i.height)
 		if !keepPendingPixels {
 			i.pixels = nil
 		}
@@ -166,7 +166,7 @@ func (i *Image) DumpScreenshot(graphicsDriver graphicsdriver.Graphics, name stri
 	return i.img.DumpScreenshot(graphicsDriver, name, blackbg)
 }
 
-func (i *Image) ReplacePixels(graphicsDriver graphicsdriver.Graphics, pix []byte, x, y, width, height int) error {
+func (i *Image) ReplaceLargeAreaPixels(pix []byte, x, y, width, height int) error {
 	if l := 4 * width * height; len(pix) != l {
 		panic(fmt.Sprintf("buffered: len(pix) was %d but must be %d", len(pix), l))
 	}
@@ -175,7 +175,29 @@ func (i *Image) ReplacePixels(graphicsDriver graphicsdriver.Graphics, pix []byte
 		copied := make([]byte, len(pix))
 		copy(copied, pix)
 		if tryAddDelayedCommand(func() error {
-			i.ReplacePixels(graphicsDriver, copied, x, y, width, height)
+			i.ReplaceLargeAreaPixels(copied, x, y, width, height)
+			return nil
+		}) {
+			return nil
+		}
+	}
+
+	i.invalidatePendingPixels()
+
+	i.img.ReplacePixels(pix, x, y, width, height)
+	return nil
+}
+
+func (i *Image) ReplaceSmallAreaPixels(graphicsDriver graphicsdriver.Graphics, pix []byte, x, y, width, height int) error {
+	if l := 4 * width * height; len(pix) != l {
+		panic(fmt.Sprintf("buffered: len(pix) was %d but must be %d", len(pix), l))
+	}
+
+	if maybeCanAddDelayedCommand() {
+		copied := make([]byte, len(pix))
+		copy(copied, pix)
+		if tryAddDelayedCommand(func() error {
+			i.ReplaceSmallAreaPixels(graphicsDriver, copied, x, y, width, height)
 			return nil
 		}) {
 			return nil
@@ -188,7 +210,7 @@ func (i *Image) ReplacePixels(graphicsDriver graphicsdriver.Graphics, pix []byte
 		// Call ReplacePixels immediately. Do not buffer the command.
 		// If a lot of new images are created but they are used at different timings,
 		// pixels are sent to GPU at different timings, which is very inefficient.
-		i.img.ReplacePixels(pix)
+		i.img.ReplacePixels(pix, x, y, width, height)
 		return nil
 	}
 

internal/mipmap/mipmap.go

@@ -71,8 +71,16 @@ func (m *Mipmap) DumpScreenshot(graphicsDriver graphicsdriver.Graphics, name str
 	return m.orig.DumpScreenshot(graphicsDriver, name, blackbg)
 }
 
-func (m *Mipmap) ReplacePixels(graphicsDriver graphicsdriver.Graphics, pix []byte, x, y, width, height int) error {
-	if err := m.orig.ReplacePixels(graphicsDriver, pix, x, y, width, height); err != nil {
+func (m *Mipmap) ReplaceLargeAreaPixels(pix []byte, x, y, width, height int) error {
+	if err := m.orig.ReplaceLargeAreaPixels(pix, x, y, width, height); err != nil {
+		return err
+	}
+	m.disposeMipmaps()
+	return nil
+}
+
+func (m *Mipmap) ReplaceSmallAreaPixels(graphicsDriver graphicsdriver.Graphics, pix []byte, x, y, width, height int) error {
+	if err := m.orig.ReplaceSmallAreaPixels(graphicsDriver, pix, x, y, width, height); err != nil {
 		return err
 	}
 	m.disposeMipmaps()

internal/ui/image.go

@@ -60,8 +60,12 @@ func (i *Image) DrawTriangles(srcs [graphics.ShaderImageNum]*Image, vertices []f
 	i.mipmap.DrawTriangles(srcMipmaps, vertices, indices, colorm, mode, filter, address, dstRegion, srcRegion, subimageOffsets, s, uniforms, evenOdd, canSkipMipmap)
 }
 
-func (i *Image) ReplacePixels(pix []byte, x, y, width, height int) error {
-	return i.mipmap.ReplacePixels(graphicsDriver(), pix, x, y, width, height)
+func (i *Image) ReplaceLargeAreaPixels(pix []byte, x, y, width, height int) error {
+	return i.mipmap.ReplaceLargeAreaPixels(pix, x, y, width, height)
+}
+
+func (i *Image) ReplaceSmallAreaPixels(pix []byte, x, y, width, height int) error {
+	return i.mipmap.ReplaceSmallAreaPixels(graphicsDriver(), pix, x, y, width, height)
 }
 
 func (i *Image) Pixels(x, y, width, height int) ([]byte, error) {