Refactoring

example/main.go

@@ -96,19 +96,19 @@ func main() {
 		}
 	}()
 
-	frameTime := time.Duration(int64(time.Second) / 120)
-	tick := time.Tick(frameTime)
 	for {
 		ui.PollEvents()
 		select {
 		default:
 			drawing <- graphics.NewLazyCanvas()
 			canvas := <-drawing
+
 			window.Draw(func(actualCanvas graphics.Canvas) {
 				canvas.Flush(actualCanvas)
 			})
-			// To avoid a busy loop, take a rest after drawing.
-			<-tick
+			after := time.After(time.Duration(int64(time.Second) / 120))
+			ui.PollEvents()
+			<-after
 		case <-quit:
 			return
 		}

graphics/opengl/shader/draw_texture.go

@@ -9,14 +9,17 @@ import (
 	"github.com/hajimehoshi/go-ebiten/graphics/matrix"
 	"github.com/hajimehoshi/go-ebiten/graphics/opengl/texture"
 	gtexture "github.com/hajimehoshi/go-ebiten/graphics/texture"
+	"sync"
 	"unsafe"
 )
 
+var once sync.Once
+
 func DrawTexture(native texture.Native, projectionMatrix [16]float32, quads []gtexture.Quad,
 	geometryMatrix matrix.Geometry, colorMatrix matrix.Color) {
-	if !initialized {
+	once.Do(func() {
 		initialize()
-	}
+	})
 
 	if len(quads) == 0 {
 		return
@@ -28,14 +31,14 @@ func DrawTexture(native texture.Native, projectionMatrix [16]float32, quads []gt
 	defer C.glBindTexture(C.GL_TEXTURE_2D, 0)
 
 	vertexAttrLocation := getAttributeLocation(shaderProgram, "vertex")
-	textureAttrLocation := getAttributeLocation(shaderProgram, "texture")
+	texCoordAttrLocation := getAttributeLocation(shaderProgram, "tex_coord")
 
 	C.glEnableClientState(C.GL_VERTEX_ARRAY)
 	C.glEnableClientState(C.GL_TEXTURE_COORD_ARRAY)
 	C.glEnableVertexAttribArray(C.GLuint(vertexAttrLocation))
-	C.glEnableVertexAttribArray(C.GLuint(textureAttrLocation))
+	C.glEnableVertexAttribArray(C.GLuint(texCoordAttrLocation))
 	defer func() {
-		C.glDisableVertexAttribArray(C.GLuint(textureAttrLocation))
+		C.glDisableVertexAttribArray(C.GLuint(texCoordAttrLocation))
 		C.glDisableVertexAttribArray(C.GLuint(vertexAttrLocation))
 		C.glDisableClientState(C.GL_TEXTURE_COORD_ARRAY)
 		C.glDisableClientState(C.GL_VERTEX_ARRAY)
@@ -75,7 +78,7 @@ func DrawTexture(native texture.Native, projectionMatrix [16]float32, quads []gt
 	C.glVertexAttribPointer(C.GLuint(vertexAttrLocation), 2,
 		C.GL_FLOAT, C.GL_FALSE,
 		0, unsafe.Pointer(&vertices[0]))
-	C.glVertexAttribPointer(C.GLuint(textureAttrLocation), 2,
+	C.glVertexAttribPointer(C.GLuint(texCoordAttrLocation), 2,
 		C.GL_FLOAT, C.GL_FALSE,
 		0, unsafe.Pointer(&texCoords[0]))
 	C.glDrawElements(C.GL_TRIANGLES, C.GLsizei(len(indicies)),

graphics/opengl/shader/program.go

@@ -48,8 +48,6 @@ func (p *program) create() {
 	}
 }
 
-var initialized = false
-
 func initialize() {
 	for _, shader := range shaders {
 		shader.compile()
@@ -63,24 +61,24 @@ func initialize() {
 	for _, program := range programs {
 		program.create()
 	}
-
-	initialized = true
 }
 
+type qualifierVariableType int
+
 const (
-	qualifierVariableTypeAttribute = iota
+	qualifierVariableTypeAttribute qualifierVariableType = iota
 	qualifierVariableTypeUniform
 )
 
 var (
-	shaderLocationCache = map[int]map[string]C.GLint{
+	shaderLocationCache = map[qualifierVariableType]map[string]C.GLint{
 		qualifierVariableTypeAttribute: map[string]C.GLint{},
 		qualifierVariableTypeUniform:   map[string]C.GLint{},
 	}
 )
 
-func getLocation(program C.GLuint, name string, qualifierVariableType int) C.GLint {
-	if location, ok := shaderLocationCache[qualifierVariableType][name]; ok {
+func getLocation(program C.GLuint, name string, qvType qualifierVariableType) C.GLint {
+	if location, ok := shaderLocationCache[qvType][name]; ok {
 		return location
 	}
 
@@ -89,7 +87,7 @@ func getLocation(program C.GLuint, name string, qualifierVariableType int) C.GLi
 
 	location := C.GLint(-1)
 
-	switch qualifierVariableType {
+	switch qvType {
 	case qualifierVariableTypeAttribute:
 		location = C.glGetAttribLocation(program, (*C.GLchar)(locationName))
 	case qualifierVariableTypeUniform:
@@ -100,7 +98,7 @@ func getLocation(program C.GLuint, name string, qualifierVariableType int) C.GLi
 	if location == -1 {
 		panic("glGetUniformLocation failed")
 	}
-	shaderLocationCache[qualifierVariableType][name] = location
+	shaderLocationCache[qvType][name] = location
 
 	return location
 }

graphics/opengl/shader/shader.go

@@ -29,14 +29,14 @@ var shaders = map[shaderId]*shader{
 	shaderVertex: &shader{
 		shaderType: C.GL_VERTEX_SHADER,
 		source: `
-attribute vec2 vertex;
-attribute vec2 texture;
 uniform mat4 projection_matrix;
 uniform mat4 modelview_matrix;
-varying vec2 tex_coord;
+attribute vec2 vertex;
+attribute vec2 tex_coord;
+varying vec2 vertex_out_tex_coord;
 
 void main(void) {
-  tex_coord = texture;
+  vertex_out_tex_coord = tex_coord;
   gl_Position = projection_matrix * modelview_matrix * vec4(vertex, 0, 1);
 }
 `,
@@ -45,10 +45,10 @@ void main(void) {
 		shaderType: C.GL_FRAGMENT_SHADER,
 		source: `
 uniform sampler2D texture;
-varying vec2 tex_coord;
+varying vec2 vertex_out_tex_coord;
 
 void main(void) {
-  gl_FragColor = texture2D(texture, tex_coord);
+  gl_FragColor = texture2D(texture, vertex_out_tex_coord);
 }
 `,
 	},
@@ -58,10 +58,10 @@ void main(void) {
 uniform sampler2D texture;
 uniform mat4 color_matrix;
 uniform vec4 color_matrix_translation;
-varying vec2 tex_coord;
+varying vec2 vertex_out_tex_coord;
 
 void main(void) {
-  vec4 color = texture2D(texture, tex_coord);
+  vec4 color = texture2D(texture, vertex_out_tex_coord);
   gl_FragColor = (color_matrix * color) + color_matrix_translation;
 }
 `,