internal/graphics: reland: change the definition of MaxVerticesCount

Updates #2612

image.go

@@ -438,9 +438,6 @@ func (i *Image) DrawTriangles(vertices []Vertex, indices []uint16, img *Image, o
 		if int(idx) >= len(vertices) {
 			panic(fmt.Sprintf("ebiten: indices[%d] must be less than len(vertices) (%d) but was %d", i, len(vertices), idx))
 		}
-		if idx >= MaxVerticesCount {
-			panic(fmt.Sprintf("ebiten: indices[%d] must be less than MaxVerticesCount %d but was %d", i, MaxVerticesCount, idx))
-		}
 	}
 
 	if options == nil {
@@ -603,9 +600,6 @@ func (i *Image) DrawTrianglesShader(vertices []Vertex, indices []uint16, shader
 		if int(idx) >= len(vertices) {
 			panic(fmt.Sprintf("ebiten: indices[%d] must be less than len(vertices) (%d) but was %d", i, len(vertices), idx))
 		}
-		if idx >= MaxVerticesCount {
-			panic(fmt.Sprintf("ebiten: indices[%d] must be less than MaxVerticesCount %d but was %d", i, MaxVerticesCount, idx))
-		}
 	}
 
 	if options == nil {

image_test.go

@@ -2805,7 +2805,7 @@ func BenchmarkColorMScale(b *testing.B) {
 	}
 }
 
-func TestIndicesOverflow(t *testing.T) {
+func TestImageMoreIndicesThanMaxUint16(t *testing.T) {
 	const (
 		w = 16
 		h = 16
@@ -2817,10 +2817,10 @@ func TestIndicesOverflow(t *testing.T) {
 
 	op := &ebiten.DrawTrianglesOptions{}
 	vs := make([]ebiten.Vertex, 3)
-	is := make([]uint16, graphics.MaxVerticesCount/3*3)
+	is := make([]uint16, 65538)
 	dst.DrawTriangles(vs, is, src, op)
 
-	// Cause an overflow for indices.
+	// The next draw call should work well (and this is likely batched).
 	vs = []ebiten.Vertex{
 		{
 			DstX:   0,
@@ -2877,7 +2877,7 @@ func TestIndicesOverflow(t *testing.T) {
 	}
 }
 
-func TestVerticesOverflow(t *testing.T) {
+func TestImageMoreVerticesThanMaxUint16(t *testing.T) {
 	const (
 		w = 16
 		h = 16
@@ -2888,11 +2888,11 @@ func TestVerticesOverflow(t *testing.T) {
 	src.Fill(color.White)
 
 	op := &ebiten.DrawTrianglesOptions{}
-	vs := make([]ebiten.Vertex, graphics.MaxVerticesCount-1)
+	vs := make([]ebiten.Vertex, math.MaxUint16+1)
 	is := make([]uint16, 3)
 	dst.DrawTriangles(vs, is, src, op)
 
-	// Cause an overflow for vertices.
+	// The next draw call should work well (and this is likely batched).
 	vs = []ebiten.Vertex{
 		{
 			DstX:   0,
@@ -2949,26 +2949,6 @@ func TestVerticesOverflow(t *testing.T) {
 	}
 }
 
-func TestTooManyVertices(t *testing.T) {
-	const (
-		w = 16
-		h = 16
-	)
-
-	dst := ebiten.NewImage(w, h)
-	src := ebiten.NewImage(w, h)
-	src.Fill(color.White)
-
-	op := &ebiten.DrawTrianglesOptions{}
-	vs := make([]ebiten.Vertex, graphics.MaxVerticesCount+1)
-	is := make([]uint16, 3)
-	dst.DrawTriangles(vs, is, src, op)
-
-	// Force to cause flushing the graphics commands.
-	// Confirm this doesn't freeze.
-	dst.At(0, 0)
-}
-
 func TestImageNewImageFromEbitenImage(t *testing.T) {
 	const (
 		w = 16
@@ -4318,48 +4298,6 @@ func TestImageDrawTrianglesShaderWithGreaterIndexThanVerticesCount(t *testing.T)
 	dst.DrawTrianglesShader(vs, is, shader, nil)
 }
 
-// Issue #2611
-func TestImageDrawTrianglesWithTooBigIndex(t *testing.T) {
-	defer func() {
-		if r := recover(); r == nil {
-			t.Errorf("DrawTriangles must panic but not")
-		}
-	}()
-
-	const w, h = 16, 16
-	dst := ebiten.NewImage(w, h)
-	src := ebiten.NewImage(w, h)
-
-	vs := make([]ebiten.Vertex, ebiten.MaxVerticesCount+1)
-	is := []uint16{0, 1, 2, 1, 2, ebiten.MaxVerticesCount}
-	dst.DrawTriangles(vs, is, src, nil)
-}
-
-// Issue #2611
-func TestImageDrawTrianglesShaderWithTooBigIndex(t *testing.T) {
-	defer func() {
-		if r := recover(); r == nil {
-			t.Errorf("DrawTrianglesShader must panic but not")
-		}
-	}()
-
-	const w, h = 16, 16
-	dst := ebiten.NewImage(w, h)
-
-	vs := make([]ebiten.Vertex, ebiten.MaxVerticesCount+1)
-	is := []uint16{0, 1, 2, 1, 2, ebiten.MaxVerticesCount}
-	shader, err := ebiten.NewShader([]byte(`
-		package main
-		func Fragment(dstPos vec4, srcPos vec2, color vec4) vec4 {
-			return color
-		}
-	`))
-	if err != nil {
-		t.Fatalf("could not compile shader: %v", err)
-	}
-	dst.DrawTrianglesShader(vs, is, shader, nil)
-}
-
 // Issue #2733
 func TestImageGeoMAfterDraw(t *testing.T) {
 	src := ebiten.NewImage(1, 1)

internal/graphics/vertex.go

@@ -45,13 +45,18 @@ const (
 const (
 	VertexFloatCount = 8
 
+	is32bit = 1 >> (^uint(0) >> 63)
+	is64bit = 1 - is32bit
+
 	// MaxVerticesCount is the maximum number of vertices for one draw call.
-	// This value is 2^16 - 1 = 65535, as the index type is uint16.
+	//
-	// This value cannot be exactly 2^16 == 65536 especially with WebGL 2, as 65536th vertex is not rendered correctly.
+	// On 64bit architectures, this value is 2^32-1, as the index type is uint32.
+	// This value cannot be exactly 2^32 especially with WebGL 2, as 2^32th vertex is not rendered correctly.
 	// See https://registry.khronos.org/webgl/specs/latest/2.0/#5.18 .
 	//
-	// TODO: Use MaxUint32 and move these values to internal/graphicscommand (#2612)
+	// On 32bit architectures, this value is an adjusted number so that MaxVertexFloatsCount doesn't overflow int.
-	MaxVerticesCount     = math.MaxUint16
+	MaxVerticesCount = is64bit*math.MaxUint32 + is32bit*(math.MaxInt32/VertexFloatCount)
+
 	MaxVertexFloatsCount = MaxVerticesCount * VertexFloatCount
 )
 

internal/ui/image.go

@@ -139,8 +139,7 @@ func (i *Image) WritePixels(pix []byte, region image.Rectangle) {
 		copy(clr[:], pix)
 		i.dotsBuffer[region.Min] = clr
 
-		// One square requires 6 indices (= 2 triangles).
+		if len(i.dotsBuffer) >= 10000 {
-		if len(i.dotsBuffer) >= graphics.MaxVerticesCount/6 {
 			i.flushDotsBufferIfNeeded()
 		}
 		return