ebiten: Remove user-defined vertex shaders

Fixes #1253

examples/shader/default.go

@@ -21,21 +21,12 @@ var Cursor vec2
 
 // viewportSize is a predefined function.
 
-func Vertex(position vec2, texCoord vec2, color vec4) vec4 {
-	return mat4(
-		2/viewportSize().x, 0, 0, 0,
-		0, 2/viewportSize().y, 0, 0,
-		0, 0, 1, 0,
-		-1, -1, 0, 1,
-	) * vec4(position, 0, 1)
-}
-
-func Fragment(position vec4) vec4 {
+func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
 	pos := position.xy/viewportSize() + Cursor/viewportSize()/4
-	color := 0.0
-	color += sin(pos.x*cos(Time/15)*80) + cos(pos.y*cos(Time/15)*10)
-	color += sin(pos.y*sin(Time/10)*40) + cos(pos.x*sin(Time/25)*40)
-	color += sin(pos.x*sin(Time/5)*10) + sin(pos.y*sin(Time/35)*80)
-	color *= sin(Time/10) * 0.5
-	return vec4(color, color*0.5, sin(color+Time/3)*0.75, 1)
+	clr := 0.0
+	clr += sin(pos.x*cos(Time/15)*80) + cos(pos.y*cos(Time/15)*10)
+	clr += sin(pos.y*sin(Time/10)*40) + cos(pos.x*sin(Time/25)*40)
+	clr += sin(pos.x*sin(Time/5)*10) + sin(pos.y*sin(Time/35)*80)
+	clr *= sin(Time/10) * 0.5
+	return vec4(clr, clr*0.5, sin(clr+Time/3)*0.75, 1)
 }

examples/shader/default_go.go

@@ -3,4 +3,4 @@
 
 package main
 
-var default_go = []byte("// Copyright 2020 The Ebiten Authors\n//\n// Licensed under the Apache License, Version 2.0 (the \"License\");\n// you may not use this file except in compliance with the License.\n// You may obtain a copy of the License at\n//\n//     http://www.apache.org/licenses/LICENSE-2.0\n//\n// Unless required by applicable law or agreed to in writing, software\n// distributed under the License is distributed on an \"AS IS\" BASIS,\n// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\n// See the License for the specific language governing permissions and\n// limitations under the License.\n\n// +build ignore\n\npackage main\n\nvar Time float\nvar Cursor vec2\n\n// viewportSize is a predefined function.\n\nfunc Vertex(position vec2, texCoord vec2, color vec4) vec4 {\n\treturn mat4(\n\t\t2/viewportSize().x, 0, 0, 0,\n\t\t0, 2/viewportSize().y, 0, 0,\n\t\t0, 0, 1, 0,\n\t\t-1, -1, 0, 1,\n\t) * vec4(position, 0, 1)\n}\n\nfunc Fragment(position vec4) vec4 {\n\tpos := position.xy/viewportSize() + Cursor/viewportSize()/4\n\tcolor := 0.0\n\tcolor += sin(pos.x*cos(Time/15)*80) + cos(pos.y*cos(Time/15)*10)\n\tcolor += sin(pos.y*sin(Time/10)*40) + cos(pos.x*sin(Time/25)*40)\n\tcolor += sin(pos.x*sin(Time/5)*10) + sin(pos.y*sin(Time/35)*80)\n\tcolor *= sin(Time/10) * 0.5\n\treturn vec4(color, color*0.5, sin(color+Time/3)*0.75, 1)\n}\n")
+var default_go = []byte("// Copyright 2020 The Ebiten Authors\n//\n// Licensed under the Apache License, Version 2.0 (the \"License\");\n// you may not use this file except in compliance with the License.\n// You may obtain a copy of the License at\n//\n//     http://www.apache.org/licenses/LICENSE-2.0\n//\n// Unless required by applicable law or agreed to in writing, software\n// distributed under the License is distributed on an \"AS IS\" BASIS,\n// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\n// See the License for the specific language governing permissions and\n// limitations under the License.\n\n// +build ignore\n\npackage main\n\nvar Time float\nvar Cursor vec2\n\n// viewportSize is a predefined function.\n\nfunc Fragment(position vec4, texCoord vec2, color vec4) vec4 {\n\tpos := position.xy/viewportSize() + Cursor/viewportSize()/4\n\tclr := 0.0\n\tclr += sin(pos.x*cos(Time/15)*80) + cos(pos.y*cos(Time/15)*10)\n\tclr += sin(pos.y*sin(Time/10)*40) + cos(pos.x*sin(Time/25)*40)\n\tclr += sin(pos.x*sin(Time/5)*10) + sin(pos.y*sin(Time/35)*80)\n\tclr *= sin(Time/10) * 0.5\n\treturn vec4(clr, clr*0.5, sin(clr+Time/3)*0.75, 1)\n}\n")

examples/shader/lighting.go

@@ -19,16 +19,7 @@ package main
 var Time float
 var Cursor vec2
 
-func Vertex(position vec2, texCoord vec2, color vec4) (vec4, vec2) {
-	return mat4(
-		2/viewportSize().x, 0, 0, 0,
-		0, 2/viewportSize().y, 0, 0,
-		0, 0, 1, 0,
-		-1, -1, 0, 1,
-	) * vec4(position, 0, 1), texCoord
-}
-
-func Fragment(position vec4, texCoord vec2) vec4 {
+func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
 	lightpos := vec3(Cursor, 50)
 	lightdir := normalize(lightpos - position.xyz)
 	normal := normalize(texture1At(texCoord) - 0.5)

examples/shader/lighting_go.go

@@ -3,4 +3,4 @@
 
 package main
 
-var lighting_go = []byte("// Copyright 2020 The Ebiten Authors\n//\n// Licensed under the Apache License, Version 2.0 (the \"License\");\n// you may not use this file except in compliance with the License.\n// You may obtain a copy of the License at\n//\n//     http://www.apache.org/licenses/LICENSE-2.0\n//\n// Unless required by applicable law or agreed to in writing, software\n// distributed under the License is distributed on an \"AS IS\" BASIS,\n// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\n// See the License for the specific language governing permissions and\n// limitations under the License.\n\n// +build ignore\n\npackage main\n\nvar Time float\nvar Cursor vec2\n\nfunc Vertex(position vec2, texCoord vec2, color vec4) (vec4, vec2) {\n\treturn mat4(\n\t\t2/viewportSize().x, 0, 0, 0,\n\t\t0, 2/viewportSize().y, 0, 0,\n\t\t0, 0, 1, 0,\n\t\t-1, -1, 0, 1,\n\t) * vec4(position, 0, 1), texCoord\n}\n\nfunc Fragment(position vec4, texCoord vec2) vec4 {\n\tlightpos := vec3(Cursor, 50)\n\tlightdir := normalize(lightpos - position.xyz)\n\tnormal := normalize(texture1At(texCoord) - 0.5)\n\tambient := 0.25\n\tdiffuse := 0.75 * max(0.0, dot(normal.xyz, lightdir))\n\treturn texture0At(texCoord) * (ambient + diffuse)\n}\n")
+var lighting_go = []byte("// Copyright 2020 The Ebiten Authors\n//\n// Licensed under the Apache License, Version 2.0 (the \"License\");\n// you may not use this file except in compliance with the License.\n// You may obtain a copy of the License at\n//\n//     http://www.apache.org/licenses/LICENSE-2.0\n//\n// Unless required by applicable law or agreed to in writing, software\n// distributed under the License is distributed on an \"AS IS\" BASIS,\n// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\n// See the License for the specific language governing permissions and\n// limitations under the License.\n\n// +build ignore\n\npackage main\n\nvar Time float\nvar Cursor vec2\n\nfunc Fragment(position vec4, texCoord vec2, color vec4) vec4 {\n\tlightpos := vec3(Cursor, 50)\n\tlightdir := normalize(lightpos - position.xyz)\n\tnormal := normalize(texture1At(texCoord) - 0.5)\n\tambient := 0.25\n\tdiffuse := 0.75 * max(0.0, dot(normal.xyz, lightdir))\n\treturn texture0At(texCoord) * (ambient + diffuse)\n}\n")

examples/shader/main.go

@@ -108,28 +108,44 @@ func (g *Game) Draw(screen *ebiten.Image) {
 	w, h := screen.Size()
 	vs := []ebiten.Vertex{
 		{
-			DstX: 0,
-			DstY: 0,
-			SrcX: 0,
-			SrcY: 0,
+			DstX:   0,
+			DstY:   0,
+			SrcX:   0,
+			SrcY:   0,
+			ColorR: 1,
+			ColorG: 1,
+			ColorB: 1,
+			ColorA: 1,
 		},
 		{
-			DstX: float32(w),
-			DstY: 0,
-			SrcX: float32(sw),
-			SrcY: 0,
+			DstX:   float32(w),
+			DstY:   0,
+			SrcX:   float32(sw),
+			SrcY:   0,
+			ColorR: 1,
+			ColorG: 1,
+			ColorB: 1,
+			ColorA: 1,
 		},
 		{
-			DstX: 0,
-			DstY: float32(h),
-			SrcX: 0,
-			SrcY: float32(sh),
+			DstX:   0,
+			DstY:   float32(h),
+			SrcX:   0,
+			SrcY:   float32(sh),
+			ColorR: 1,
+			ColorG: 1,
+			ColorB: 1,
+			ColorA: 1,
 		},
 		{
-			DstX: float32(w),
-			DstY: float32(h),
-			SrcX: float32(sw),
-			SrcY: float32(sh),
+			DstX:   float32(w),
+			DstY:   float32(h),
+			SrcX:   float32(sw),
+			SrcY:   float32(sh),
+			ColorR: 1,
+			ColorG: 1,
+			ColorB: 1,
+			ColorA: 1,
 		},
 	}
 	is := []uint16{0, 1, 2, 1, 2, 3}

internal/shader/shader.go

@@ -95,6 +95,9 @@ type block struct {
 	ir shaderir.Block
 }
 
+// TODO: Consider variable/attrbutes!
+// Probably creating a local variable for them automatically would be nice!
+// However, what if the name is shadowing arguments? -> cause the error!
 func (b *block) findLocalVariable(name string) (int, shaderir.Type, bool) {
 	idx := 0
 	for outer := b.outer; outer != nil; outer = outer.outer {

shader.go

@@ -34,6 +34,15 @@ var __viewportSize vec2
 func viewportSize() vec2 {
 	return __viewportSize
 }
+
+func __vertex(position vec2, texCoord vec2, color vec4) (vec4, vec2, vec4) {
+	return mat4(
+		2/viewportSize().x, 0, 0, 0,
+		0, 2/viewportSize().y, 0, 0,
+		0, 0, 1, 0,
+		-1, -1, 0, 1,
+	) * vec4(position, 0, 1), texCoord, color
+}
 `
 
 	for i := 1; i < graphics.ShaderImageNum; i++ {
@@ -72,7 +81,7 @@ func NewShader(src []byte) (*Shader, error) {
 	}
 
 	// TODO: Create a pseudo vertex entrypoint to treat the attribute values correctly.
-	s, err := shader.Compile(fs, f, "Vertex", "Fragment", graphics.ShaderImageNum)
+	s, err := shader.Compile(fs, f, "__vertex", "Fragment", graphics.ShaderImageNum)
 	if err != nil {
 		return nil, err
 	}