Golang gl.Enable函数代码示例

// initGL initializes GLFW and OpenGL.
func initGL() error {
	err := glfw.Init()
	if err != nil {
		return err
	}

	err = glfw.OpenWindow(AtlasSize, AtlasSize, 8, 8, 8, 8, 0, 0, glfw.Windowed)
	if err != nil {
		glfw.Terminate()
		return err
	}

	glfw.SetWindowTitle("Texture atlas example")
	glfw.SetSwapInterval(1)
	glfw.SetWindowSizeCallback(onResize)
	glfw.SetKeyCallback(onKey)

	gl.Init()
	if err = glh.CheckGLError(); err != nil {
		return err
	}

	gl.Disable(gl.DEPTH_TEST)
	gl.Disable(gl.LIGHTING)
	gl.Enable(gl.TEXTURE_2D)
	gl.Enable(gl.BLEND)
	gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
	gl.ClearColor(0.2, 0.2, 0.23, 1.0)
	return nil
}

// NewRenderer creates a new Renderer with the given window size and title.
func NewRenderer(window *Window) (*Renderer, error) {
	logger.Debug("Initializing GLEW")

	// Init glew
	if gl.Init() != 0 {
		return nil, errors.New("Could not initialise glew.")
	}
	gl.GetError()

	if window.Settings.ClearColor != nil {
		color := window.Settings.ClearColor
		gl.ClearColor(
			gl.GLclampf(color.R()),
			gl.GLclampf(color.G()),
			gl.GLclampf(color.B()),
			0.,
		)
	}

	gl.Enable(gl.DEPTH_TEST)
	gl.DepthFunc(gl.LESS)

	gl.Enable(gl.CULL_FACE)

	// Vertex buffers
	vertexArray := gl.GenVertexArray()
	vertexArray.Bind()

	renderer := Renderer{
		vertexArray: vertexArray,
		window:      window,
	}
	return &renderer, nil
}

func (m *Map) Draw() {

	// gl.Enable(gl.PRIMITIVE_RESTART)
	// gl.PrimitiveRestartIndex(PRIMITIVE_RESTART)
	gl.EnableClientState(gl.VERTEX_ARRAY)
	gl.Translatef(float32(m.gridSize/2), float32(m.gridSize/2), 0)

	if m.renderSmooth {
		gl.Enable(gl.BLEND)
		gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
		gl.Enable(gl.POLYGON_SMOOTH)
		gl.Hint(gl.POLYGON_SMOOTH_HINT, gl.NICEST)
	}

	if m.renderMode == 1 {
		gl.LineWidth(1)
		gl.VertexPointer(2, gl.FLOAT, 0, m.gridLines)
		gl.Color3f(0.2, 0.2, 0.2)
		gl.DrawArrays(gl.LINES, 0, len(m.gridLines)/2)
		gl.PolygonMode(gl.FRONT_AND_BACK, gl.LINE)
	}

	for _, vl := range m.vl {
		if len(vl.vertices) > 0 {
			gl.VertexPointer(2, gl.FLOAT, 0, vl.vertices)
			gl.Color3f(vl.colors[0], vl.colors[1], vl.colors[2])
			gl.DrawElements(gl.TRIANGLES, len(vl.indices), gl.UNSIGNED_INT, vl.indices)
		}
	}

}

func (r *RenderTarget) resetGlStates() {
	// Define the default OpenGL states
	gl.Disable(gl.CULL_FACE)
	gl.Disable(gl.LIGHTING)
	gl.Disable(gl.DEPTH_TEST)
	gl.Disable(gl.ALPHA_TEST)
	gl.Enable(gl.TEXTURE_2D)
	gl.Enable(gl.BLEND)
	gl.MatrixMode(gl.MODELVIEW)
	gl.EnableClientState(gl.VERTEX_ARRAY)
	gl.EnableClientState(gl.COLOR_ARRAY)
	gl.EnableClientState(gl.TEXTURE_COORD_ARRAY)
	r.glStatesSet = true

	// Apply the default SFML states
	r.applyBlendMode(BlendAlpha)
	r.applyTransform(IdentityTransform())
	r.applyTexture(nil)
	/*if (Shader::isAvailable()){
		r.applyShader(nil)
	}*/
	r.useVertexCache = false

	// Set the default view
	r.SetView(r.View())
}

func (pen *Pen) lineTo(x, y int) {
	gl.Enable(gl.BLEND)
	gl.Enable(gl.POINT_SMOOTH)
	gl.Enable(gl.LINE_SMOOTH)
	gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
	gl.Color4f(0.0, 0.0, 0.0, 0.1)
	gl.Begin(gl.LINES)

	var p [2]int
	for i := range pen.points {
		p = pen.points[i]
		if p[0] == 0 && p[1] == 0 {
			continue
		}

		if distanceTo(x, y, p[0], p[1]) < 10.0 {
			gl.Vertex2i(x, y)
			gl.Vertex2i(p[0], p[1])
		}
	}

	gl.End()

	pen.n = (pen.n + 1) % len(pen.points)
	pen.points[pen.n][0] = x
	pen.points[pen.n][1] = y
	pen.moveTo(x, y)
}

func initGL() (err error) {

	goph, err := os.Open(texturefiles[0])
	if err != nil {
		panic(err)
	}
	defer goph.Close()

	texture, err = createTexture(goph)

	gl.ShadeModel(gl.SMOOTH)
	gl.ClearColor(0, 0, 0, 0.5)
	gl.ClearDepth(1)
	gl.Hint(gl.PERSPECTIVE_CORRECTION_HINT, gl.NICEST)
	gl.BlendFunc(gl.SRC_ALPHA, gl.ONE) // 设置混色函数取得半透明效果
	gl.Enable(gl.BLEND)
	gl.Enable(gl.TEXTURE_2D)

	rand.Seed(time.Now().Unix())
	for loop = 0; loop < num; loop++ {
		star[loop].angle = 0.0
		star[loop].dist = float32(loop) / num * 5
		//fmt.Println(loop, star[loop].dist)
		star[loop].r = uint8(rand.Int() % 256)
		star[loop].g = uint8(rand.Int() % 256)
		star[loop].b = uint8(rand.Int() % 256)
	}

	return
}

// initGL initializes GLFW and OpenGL.
func initGL(c *cpu.CPU, width, height int) error {
	err := glfw.Init()
	if err != nil {
		return err
	}

	glfw.OpenWindowHint(glfw.WindowNoResize, 1)

	err = glfw.OpenWindow(width, height, 8, 8, 8, 8, 8, 0, glfw.Windowed)
	if err != nil {
		glfw.Terminate()
		return err
	}

	glfw.SetWindowTitle("DCPU")
	glfw.SetSwapInterval(1)
	glfw.SetWindowSizeCallback(onResize)

	gl.Init()
	err = glh.CheckGLError()
	if err != nil {
		return err
	}

	gl.Disable(gl.LIGHTING)
	gl.Disable(gl.DEPTH_TEST)
	gl.Enable(gl.TEXTURE_2D)
	gl.Enable(gl.BLEND)
	gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
	gl.ClearColor(0, 0, 0, 1)
	return err
}

func initScene() (err error) {
	gl.Enable(gl.TEXTURE_2D)
	gl.Enable(gl.DEPTH_TEST)
	gl.Enable(gl.LIGHTING)

	gl.ClearColor(0.5, 0.5, 0.5, 0.0)
	gl.ClearDepth(1)
	gl.DepthFunc(gl.LEQUAL)

	gl.Lightfv(gl.LIGHT0, gl.AMBIENT, ambient)
	gl.Lightfv(gl.LIGHT0, gl.DIFFUSE, diffuse)
	gl.Lightfv(gl.LIGHT0, gl.POSITION, lightpos)
	gl.Enable(gl.LIGHT0)

	gl.Viewport(0, 0, Width, Height)
	gl.MatrixMode(gl.PROJECTION)
	gl.LoadIdentity()
	gl.Frustum(-1, 1, -1, 1, 1.0, 10.0)
	gl.MatrixMode(gl.MODELVIEW)
	gl.LoadIdentity()

	goph, err := os.Open("../../data/gopher.png")
	if err != nil {
		panic(err)
	}
	defer goph.Close()

	texture, err = createTexture(goph)
	return
}

// Opens a new window.
func (c *Controller) Open(win *Window) (err error) {
	c.Win = win
	mode := glfw.Windowed
	if win.Fullscreen {
		mode = glfw.Fullscreen
	}
	if win.Resize == false {
		glfw.OpenWindowHint(glfw.WindowNoResize, 1)
	}
	if err = glfw.OpenWindow(win.Width, win.Height, 0, 0, 0, 0, 0, 0, mode); err != nil {
		return
	}
	gl.Init()
	gl.Enable(gl.TEXTURE_2D)
	gl.Enable(gl.BLEND)
	gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
	v1, v2, v3 := glfw.GLVersion()
	log.Printf("OpenGL version: %v %v %v\n", v1, v2, v3)
	fb_supported := glfw.ExtensionSupported("GL_EXT_framebuffer_object")
	log.Printf("Framebuffer supported: %v\n", fb_supported)
	c.SetClearColor(0, 0, 0, 0)
	if win.VSync == true {
		glfw.SetSwapInterval(1) // Limit to refresh
	}
	glfw.SetWindowTitle(win.Title)
	glfw.SetWindowSizeCallback(func(w, h int) {
		log.Printf("Resizing window to %v, %v\n", w, h)
		c.resize()
	})
	err = c.resize()
	return
}

func (s *System) draw() {
	s.cmds <- func() {
		gl.Enable(gl.DEPTH_TEST)
		gl.Enable(gl.BLEND)
		gl.DepthFunc(gl.LEQUAL)
		gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
		gl.PolygonMode(gl.FRONT_AND_BACK, gl.FILL)
		//s.shader.Use()
		//s.shader.AssignUniforms(uniforms)
	}
	for _, _ = range s.meshes.layouts {
		s.submit(renderState{})
	}
	for i := range s.buckets {
		list := &s.buckets[i]
		list.sort()
		s.cmds <- list.execute
	}
	return
	/*
		s.cmds <- func() {
			for _, geom := range geoms {
				// gl state
				// texture units
				// uniforms
				//shader.AssignUniforms()
				shader.SetGeometry(&geom)
				shader.Draw()
			}
		}
	*/
}

func initGL() (err error) {
	if err = loadTextures(); err != nil {
		return
	}

	gl.ShadeModel(gl.SMOOTH)
	gl.ClearColor(0, 0, 0, 0)
	gl.ClearDepth(1)
	gl.DepthFunc(gl.LEQUAL)
	gl.Hint(gl.PERSPECTIVE_CORRECTION_HINT, gl.NICEST)
	gl.Enable(gl.TEXTURE_2D)
	gl.Enable(gl.DEPTH_TEST)

	//alpha通道的值为 0.0意味着物体材质是完全透明的。1.0 则意味着完全不透明
	//以全亮度绘制此物体，并对其进行50%的alpha混合(半透明)。
	//当混合选项打开时，此物体将会产生50%的透明效果
	gl.Color4f(1, 1, 1, 0.5)           //全亮度， 50% Alpha 混合
	gl.BlendFunc(gl.SRC_ALPHA, gl.ONE) //基于源象素alpha通道值的半透明混合函数

	gl.Lightfv(gl.LIGHT1, gl.AMBIENT, ambient)
	gl.Lightfv(gl.LIGHT1, gl.AMBIENT, diffuse)
	gl.Lightfv(gl.LIGHT1, gl.POSITION, lightpos)
	gl.Enable(gl.LIGHT1)
	return
}

func initGL() (err error) {
	if err = loadTextures(); err != nil {
		return
	}

	gl.ShadeModel(gl.SMOOTH) /// 启用阴影平滑,设置平滑着色,阴影平滑通过多边形精细的混合色彩，并对外部光进行平滑

	/*
	  色彩值的范围从0.0f到1.0f。0.0f代表最黑的情况，1.0f就是最亮的情况。
	  glClearColor 后的第一个参数是Red Intensity(红色分量),第二个是绿色，第三个是蓝色。最大值也是1.0f，代表特定颜色分量的最亮情况。
	  最后一个参数是Alpha值。当它用来清除屏幕的时候，我们不用关心第四个数字。现在让它为0.0f.
	*/
	gl.ClearColor(0, 0, 0, 0) ///设置清除屏幕时所用的颜色,黑色背景

	/*
	  接下来的三行必须做的是关于depth buffer(深度缓存)的。将深度缓存设想为屏幕后面的层。
	  深度缓存不断的对物体进入屏幕内部有多深进行跟踪。
	  本程序其实没有真正使用深度缓存，但几乎所有在屏幕上显示3D场景OpenGL程序都使用深度缓存。
	  它的排序决定那个物体先画。这样您就不会将一个圆形后面的正方形画到圆形上来。深度缓存是OpenGL十分重要的部分。
	*/
	gl.ClearDepth(1)                                   ///设置深度缓存
	gl.DepthFunc(gl.LEQUAL)                            ///所作深度测试的类型
	gl.Hint(gl.PERSPECTIVE_CORRECTION_HINT, gl.NICEST) ///告诉系统对透视进行修正,这会十分轻微的影响性能。但使得透视图看起来好一点

	gl.Enable(gl.DEPTH_TEST) ///启用深度测试
	gl.Enable(gl.TEXTURE_2D) ///启用纹理映射
	return
}

// OpenGL draw function
func draw() {
	gl.Clear(gl.COLOR_BUFFER_BIT)
	gl.Enable(gl.BLEND)
	gl.Enable(gl.POINT_SMOOTH)
	gl.Enable(gl.LINE_SMOOTH)
	gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
	gl.LoadIdentity()

	gl.Begin(gl.LINES)
	gl.Color3f(.2, .2, .2)
	for i := range staticLines {
		x := staticLines[i].GetAsSegment().A.X
		y := staticLines[i].GetAsSegment().A.Y
		gl.Vertex3f(float32(x), float32(y), 0)
		x = staticLines[i].GetAsSegment().B.X
		y = staticLines[i].GetAsSegment().B.Y
		gl.Vertex3f(float32(x), float32(y), 0)
	}
	gl.End()

	gl.Color4f(.3, .3, 1, .8)
	// draw balls
	for _, ball := range balls {
		gl.PushMatrix()
		pos := ball.Body.Position()
		rot := ball.Body.Angle() * chipmunk.DegreeConst
		gl.Translatef(float32(pos.X), float32(pos.Y), 0.0)
		gl.Rotatef(float32(rot), 0, 0, 1)
		drawCircle(float64(ballRadius), 60)
		gl.PopMatrix()
	}
}

// Binds the framebuffer for drawing.
func (fb *Framebuffer) Bind() {
	fb.Buffer.Bind()
	gl.Viewport(0, 0, fb.Width, fb.Height)
	gl.Enable(gl.TEXTURE_2D)
	gl.Disable(gl.DEPTH_TEST)
	gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
	gl.Enable(gl.BLEND)
}

func main() {
	_ = fmt.Sprint()

	if !glfw.Init() {
		panic("Can't init glfw!")
	}
	defer glfw.Terminate()

	// antialiasing
	//glfw.WindowHint(glfw.Samples, 4)

	window, err = glfw.CreateWindow(WindowWidth, WindowHeight, "Mozaik", nil, nil)
	if err != nil {
		panic(err)
	}
	defer window.Destroy()

	// Ensure thread context
	window.MakeContextCurrent()
	//glfw.SwapInterval(1)

	window.SetKeyCallback(keyCb)
	window.SetMouseButtonCallback(mouseCb)

	gl.Init()
	gl.ClearColor(0.9, 0.85, 0.46, 0.0)
	// useless in 2D
	gl.Disable(gl.DEPTH_TEST)
	// antialiasing
	gl.Enable(gl.BLEND)
	gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
	gl.Enable(gl.LINE_SMOOTH)

	for i := int32(32); i < 72; i++ {
		font := loadFonts(i)
		defer font.Release()
		fonts = append(fonts, font)
	}

	// Compute window radius
	windowRadius = math.Sqrt(math.Pow(WindowHeight, 2) + math.Pow(WindowWidth, 2))

	// Use window coordinates
	gl.MatrixMode(gl.PROJECTION)
	gl.LoadIdentity()
	gl.Ortho(0, WindowWidth, WindowHeight, 0, 0, 1)
	gl.MatrixMode(gl.MODELVIEW)
	gl.LoadIdentity()

	g = NewGame()

	g.Start()
	go eventLoop(g)
	go renderLoop(g)
	Main()
	g.Stop()
}