Simplify shaders

image.go

@@ -65,9 +65,8 @@ func (i *innerImage) drawImage(image *innerImage, parts []ImagePart, geo Geometr
 	if i.texture != nil {
 		targetNativeTexture = i.texture.Native()
 	}
-	w2, h2 := i.size()
 	projectionMatrix := i.renderTarget.ProjectionMatrix()
-	shader.DrawTexture(image.texture.Native(), targetNativeTexture, w2, h2, projectionMatrix, quads, &geo, &color)
+	shader.DrawTexture(image.texture.Native(), targetNativeTexture, projectionMatrix, quads, &geo, &color)
 	return nil
 }
 

internal/opengl/internal/shader/drawtexture.go

@@ -18,7 +18,6 @@ package shader
 
 import (
 	"github.com/go-gl/gl"
-	"github.com/hajimehoshi/ebiten/internal"
 	"sync"
 )
 
@@ -39,7 +38,7 @@ type Matrix interface {
 }
 
 // TODO: Use VBO
-func DrawTexture(native gl.Texture, target gl.Texture, width, height int, projectionMatrix [4][4]float64, quads []TextureQuad, geo Matrix, color Matrix) {
+func DrawTexture(native gl.Texture, target gl.Texture, projectionMatrix [4][4]float64, quads []TextureQuad, geo Matrix, color Matrix) {
 	once.Do(func() {
 		initialize()
 	})
@@ -50,7 +49,7 @@ func DrawTexture(native gl.Texture, target gl.Texture, width, height int, projec
 	// TODO: Check performance
 	program := gl.Program(0)
 	if 0 < target {
-		program = useProgramColorMatrix(glMatrix(projectionMatrix), width, height, geo, color)
+		program = useProgramColorMatrix(glMatrix(projectionMatrix), geo, color)
 	} else {
 		program = useProgramColorFinal(glMatrix(projectionMatrix), geo)
 	}
@@ -64,32 +63,21 @@ func DrawTexture(native gl.Texture, target gl.Texture, width, height int, projec
 	}
 
 	vertexAttrLocation := getAttributeLocation(program, "vertex")
-	texCoord0AttrLocation := getAttributeLocation(program, "tex_coord0")
+	texCoordAttrLocation := getAttributeLocation(program, "tex_coord")
-	texCoord1AttrLocation := gl.AttribLocation(0)
-	if program == programColorMatrix.native {
-		texCoord1AttrLocation = getAttributeLocation(program, "tex_coord1")
-	}
 
 	gl.EnableClientState(gl.VERTEX_ARRAY)
 	gl.EnableClientState(gl.TEXTURE_COORD_ARRAY)
 	vertexAttrLocation.EnableArray()
-	texCoord0AttrLocation.EnableArray()
+	texCoordAttrLocation.EnableArray()
-	if program == programColorMatrix.native {
-		texCoord1AttrLocation.EnableArray()
-	}
 	defer func() {
-		if program == programColorMatrix.native {
+		texCoordAttrLocation.DisableArray()
-			texCoord1AttrLocation.DisableArray()
-		}
-		texCoord0AttrLocation.DisableArray()
 		vertexAttrLocation.DisableArray()
 		gl.DisableClientState(gl.TEXTURE_COORD_ARRAY)
 		gl.DisableClientState(gl.VERTEX_ARRAY)
 	}()
 
 	vertices := []float32{}
-	texCoords0 := []float32{}
+	texCoords := []float32{}
-	texCoords1 := []float32{}
 	indicies := []uint32{}
 	// TODO: Check len(quads) and gl.MAX_ELEMENTS_INDICES?
 	for i, quad := range quads {
@@ -107,26 +95,12 @@ func DrawTexture(native gl.Texture, target gl.Texture, width, height int, projec
 		u1 := quad.TextureCoordU1
 		v0 := quad.TextureCoordV0
 		v1 := quad.TextureCoordV1
-		texCoords0 = append(texCoords0,
+		texCoords = append(texCoords,
 			u0, v0,
 			u1, v0,
 			u0, v1,
 			u1, v1,
 		)
-		if program == programColorMatrix.native {
-			w := float32(internal.NextPowerOf2Int(width))
-			h := float32(internal.NextPowerOf2Int(height))
-			xx0 := x0 / w
-			xx1 := x1 / w
-			yy0 := y0 / h
-			yy1 := y1 / h
-			texCoords1 = append(texCoords1,
-				xx0, yy0,
-				xx1, yy0,
-				xx0, yy1,
-				xx1, yy1,
-			)
-		}
 		base := uint32(i * 4)
 		indicies = append(indicies,
 			base, base+1, base+2,
@@ -134,10 +108,7 @@ func DrawTexture(native gl.Texture, target gl.Texture, width, height int, projec
 		)
 	}
 	vertexAttrLocation.AttribPointer(2, gl.FLOAT, false, 0, vertices)
-	texCoord0AttrLocation.AttribPointer(2, gl.FLOAT, false, 0, texCoords0)
+	texCoordAttrLocation.AttribPointer(2, gl.FLOAT, false, 0, texCoords)
-	if program == programColorMatrix.native {
-		texCoord1AttrLocation.AttribPointer(2, gl.FLOAT, false, 0, texCoords1)
-	}
 	gl.DrawElements(gl.TRIANGLES, len(indicies), gl.UNSIGNED_INT, indicies)
 
 	gl.Flush()

internal/opengl/internal/shader/program.go

@@ -18,7 +18,6 @@ package shader
 
 import (
 	"github.com/go-gl/gl"
-	"github.com/hajimehoshi/ebiten/internal"
 )
 
 type program struct {
@@ -31,7 +30,7 @@ var programColorMatrix = program{
 }
 
 var programColorFinal = program{
-	shaderIds: []shaderId{shaderVertexFinal, shaderColorFinal},
+	shaderIds: []shaderId{shaderVertex, shaderColorFinal},
 }
 
 func (p *program) create() {
@@ -73,7 +72,7 @@ func getUniformLocation(program gl.Program, name string) gl.UniformLocation {
 
 var lastProgram gl.Program = 0
 
-func useProgramColorMatrix(projectionMatrix [16]float32, width, height int, geo Matrix, color Matrix) gl.Program {
+func useProgramColorMatrix(projectionMatrix [16]float32, geo Matrix, color Matrix) gl.Program {
 	if lastProgram != programColorMatrix.native {
 		programColorMatrix.native.Use()
 		lastProgram = programColorMatrix.native
@@ -97,18 +96,7 @@ func useProgramColorMatrix(projectionMatrix [16]float32, width, height int, geo
 	}
 	getUniformLocation(program.native, "modelview_matrix").UniformMatrix4fv(false, glModelviewMatrix)
 
-	txn := tx / float32(internal.NextPowerOf2Int(width))
+	getUniformLocation(program.native, "texture").Uniform1i(0)
-	tyn := ty / float32(internal.NextPowerOf2Int(height))
-	glModelviewMatrixN := [...]float32{
-		a, c, 0, 0,
-		b, d, 0, 0,
-		0, 0, 1, 0,
-		txn, tyn, 0, 1,
-	}
-	getUniformLocation(program.native, "modelview_matrix_n").UniformMatrix4fv(false, glModelviewMatrixN)
-
-	getUniformLocation(program.native, "texture0").Uniform1i(0)
-	getUniformLocation(program.native, "texture1").Uniform1i(1)
 
 	e := [4][5]float32{}
 	for i := 0; i < 4; i++ {
@@ -156,7 +144,7 @@ func useProgramColorFinal(projectionMatrix [16]float32, geo Matrix) gl.Program {
 	}
 	getUniformLocation(program.native, "modelview_matrix").UniformMatrix4fv(false, glModelviewMatrix)
 
-	getUniformLocation(program.native, "texture0").Uniform1i(0)
+	getUniformLocation(program.native, "texture").Uniform1i(0)
 
 	return program.native
 }

internal/opengl/internal/shader/shader.go

@@ -42,31 +42,12 @@ var shaders = map[shaderId]*shader{
 		source: `
 uniform mat4 projection_matrix;
 uniform mat4 modelview_matrix;
-uniform mat4 modelview_matrix_n;
 attribute vec2 vertex;
-attribute vec2 tex_coord0;
+attribute vec2 tex_coord;
-attribute vec2 tex_coord1;
+varying vec2 vertex_out_tex_coord;
-varying vec2 vertex_out_tex_coord0;
-varying vec2 vertex_out_tex_coord1;
 
 void main(void) {
-  vertex_out_tex_coord0 = tex_coord0;
+  vertex_out_tex_coord = tex_coord;
-  vertex_out_tex_coord1 = (modelview_matrix_n * vec4(tex_coord1, 0, 1)).xy;
-  gl_Position = projection_matrix * modelview_matrix * vec4(vertex, 0, 1);
-}
-`,
-	},
-	shaderVertexFinal: {
-		shaderType: gl.VERTEX_SHADER,
-		source: `
-uniform mat4 projection_matrix;
-uniform mat4 modelview_matrix;
-attribute vec2 vertex;
-attribute vec2 tex_coord0;
-varying vec2 vertex_out_tex_coord0;
-
-void main(void) {
-  vertex_out_tex_coord0 = tex_coord0;
   gl_Position = projection_matrix * modelview_matrix * vec4(vertex, 0, 1);
 }
 `,
@@ -74,37 +55,33 @@ void main(void) {
 	shaderColorMatrix: {
 		shaderType: gl.FRAGMENT_SHADER,
 		source: `
-uniform sampler2D texture0;
+uniform sampler2D texture;
-uniform sampler2D texture1;
 uniform mat4 color_matrix;
 uniform vec4 color_matrix_translation;
-varying vec2 vertex_out_tex_coord0;
+varying vec2 vertex_out_tex_coord;
-varying vec2 vertex_out_tex_coord1;
 
 void main(void) {
-  vec4 color0 = texture2D(texture0, vertex_out_tex_coord0);
+  vec4 color = texture2D(texture, vertex_out_tex_coord);
-  vec4 color1 = texture2D(texture1, vertex_out_tex_coord1);
   // Un-premultiply alpha
-  color0.rgb /= color0.a;
+  color.rgb /= color.a;
   // Apply the color matrix
-  color0 = (color_matrix * color0) + color_matrix_translation;
+  color = (color_matrix * color) + color_matrix_translation;
   // Premultiply alpha
-  color0 = clamp(color0, 0.0, 1.0);
+  color = clamp(color, 0.0, 1.0);
-  color0.rgb *= color0.a;
+  color.rgb *= color.a;
 
-  gl_FragColor = color0 + (1.0 - color0.a) * color1;
+  gl_FragColor = color;
 }
 `,
 	},
 	shaderColorFinal: {
 		shaderType: gl.FRAGMENT_SHADER,
 		source: `
-uniform sampler2D texture0;
+uniform sampler2D texture;
-varying vec2 vertex_out_tex_coord0;
+varying vec2 vertex_out_tex_coord;
 
 void main(void) {
-  vec4 color0 = texture2D(texture0, vertex_out_tex_coord0);
+  gl_FragColor = texture2D(texture, vertex_out_tex_coord);
-  gl_FragColor = color0;
 }
 `,
 	},

ui.go

@@ -52,6 +52,9 @@ func init() {
 	currentUI.use(func() {
 		gl.Init()
 		gl.Enable(gl.TEXTURE_2D)
+		// Textures' pixel formats are alpha premultiplied.
+		gl.Enable(gl.BLEND)
+		gl.BlendFunc(gl.ONE, gl.ONE_MINUS_SRC_ALPHA)
 	})
 }