Golang gl.Init函数代码示例

func main() {
	if err := glfw.Init(); err != nil {
		fmt.Fprintf(os.Stderr, "%s\n", err.Error())
		return
	}
	defer glfw.Terminate()

	glfw.OpenWindowHint(glfw.FsaaSamples, 4)
	glfw.OpenWindowHint(glfw.OpenGLVersionMajor, 3)
	glfw.OpenWindowHint(glfw.OpenGLVersionMinor, 3)
	glfw.OpenWindowHint(glfw.OpenGLProfile, glfw.OpenGLCoreProfile)

	if err := glfw.OpenWindow(1024, 768, 0, 0, 0, 0, 32, 0, glfw.Windowed); err != nil {
		fmt.Fprintf(os.Stderr, "%s\n", err.Error())
		return
	}

	gl.Init()
	gl.GetError() // Ignore error

	glfw.SetWindowTitle("Tutorial 01")
	glfw.Enable(glfw.StickyKeys)

	gl.ClearColor(0., 0., 0.4, 0.)
	// Equivalent to a do... while
	for ok := true; ok; ok = (glfw.Key(glfw.KeyEsc) != glfw.KeyPress && glfw.WindowParam(glfw.Opened) == gl.TRUE) {
		glfw.SwapBuffers()
	}

}

// Initialize the window. Returns an error if glfw or glew throws one.
func InitWindow(width, height int) error {
	Width, Height = width, height
	err := glfw.Init()
	if err != nil {
		return err
	}
	err = glfw.OpenWindow(Width, Height, 0, 0, 0, 32, 32, 32, glfw.Windowed)
	if err != nil {
		return err
	}
	WindowOpened = true
	glfw.SetWindowTitle("Goliath")
	glfw.Enable(glfw.KeyRepeat)
	if ret := gl.Init(); ret != 0 {
		return fmt.Errorf("failed to initialize GLEW: %d", ret)
	}
	// Set GL states
	gl.ClearColor(0.0, 0.0, 0.0, 1.0)
	gl.Enable(gl.CULL_FACE)
	gl.CullFace(gl.BACK)
	gl.FrontFace(gl.CCW)

	err = InitShaders()
	if err != nil {
		return err
	}
	InitCamera(Width, Height)
	return nil
}

// 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
}

func (v *Video) Init(w int, h int) {
	var err error
	if err = glfw.Init(); err != nil {
		log.Fatal(err)
	}

	glfw.OpenWindowHint(glfw.WindowNoResize, gl.TRUE)

	if err = glfw.OpenWindow(w, h, 8, 8, 8, 0, 24, 0, glfw.Windowed); err != nil {
		log.Fatal(err)
	}

	if gl.Init() != 0 {
		log.Fatal("ummm... hmmm")
	}

	glfw.SetWindowSizeCallback(resize)

	gl.Enable(gl.TEXTURE_2D)

	resize(w, h)

	v.Texture = gl.GenTexture()

}

func main() {
	glfw.SetErrorCallback(errorCallback)

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

	window, err := glfw.CreateWindow(Width, Height, Title, nil, nil)
	if err != nil {
		panic(err)
	}

	window.MakeContextCurrent()

	glfw.SwapInterval(1)

	gl.Init()

	if err := initScene(); err != nil {
		fmt.Fprintf(os.Stderr, "init: %s\n", err)
		return
	}
	defer destroyScene()

	for !window.ShouldClose() {
		drawScene()
		window.SwapBuffers()
		glfw.PollEvents()
	}
}

// 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
}

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

	err = glfw.OpenWindow(640, 480, 8, 8, 8, 8, 0, 0, glfw.Windowed)
	if err != nil {
		glfw.Terminate()
		return err
	}

	glfw.SetWindowTitle("go-gl/gltext: Bitmap font example")
	glfw.SetSwapInterval(1)
	glfw.SetWindowSizeCallback(onResize)
	glfw.SetKeyCallback(onKey)

	errno := gl.Init()
	if errno != gl.NO_ERROR {
		str, err := glu.ErrorString(errno)
		if err != nil {
			return fmt.Errorf("Unknown openGL error: %d", errno)
		}
		return fmt.Errorf(str)
	}

	gl.Disable(gl.DEPTH_TEST)
	gl.Disable(gl.LIGHTING)
	gl.ClearColor(0.2, 0.2, 0.23, 0.0)
	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 main() {
	if err := glfw.Init(); err != nil {
		fmt.Fprintf(os.Stderr, "[e] %v\n", err)
		return
	}
	defer glfw.Terminate()

	if err := glfw.OpenWindow(appWidth, appHeight, 8, 8, 8, 8, 24, 8, glfw.Windowed); err != nil {
		fmt.Fprintf(os.Stderr, "[e] %v\n", err)
		return
	}
	defer glfw.CloseWindow()

	if err := gl.Init(); err != 0 {
		fmt.Fprintf(os.Stderr, "[e] %v\n", err)
		return
	}
	glfw.SetWindowTitle(title)

	fps := fps.NewFPS(glfw.Time())

	blocks.Init(appWidth, appHeight)
	for glfw.WindowParam(glfw.Opened) == 1 {
		blocks.Tick()
		fps.Tick(glfw.Time())
		if glfw.WindowParam(glfw.Active) == 1 {
			glfw.Sleep(0.001)
		} else {
			glfw.Sleep(0.05)
		}
	}
}

func make_window(w, h int, title string) func() {
	// Required to make sure that the OpenGL go-routine doesn't get switched
	// to another thread (=> kerblammo)
	runtime.LockOSThread()

	if err := glfw.Init(); err != nil {
		log.Panic("glfw Error:", err)
	}

	err := glfw.OpenWindow(w, h, 0, 0, 0, 0, 0, 0, glfw.Windowed)
	if err != nil {
		log.Panic("Error:", err)
	}

	if gl.Init() != 0 {
		log.Panic("gl error")
	}

	if *vsync {
		glfw.SetSwapInterval(1)
	} else {
		glfw.SetSwapInterval(0)
	}

	glfw.SetWindowTitle(title)
	glfw.SetWindowSizeCallback(Reshape)

	Init()

	return func() {
		glfw.Terminate()
		glfw.CloseWindow()
		log.Print("Cleanup")
	}
}

func main() {
	runtime.LockOSThread()

	if !glfw.Init() {
		fmt.Fprintf(os.Stderr, "Can't open GLFW")
		return
	}
	defer glfw.Terminate()

	glfw.WindowHint(glfw.Samples, 4)
	glfw.WindowHint(glfw.ContextVersionMajor, 3)
	glfw.WindowHint(glfw.ContextVersionMinor, 3)
	glfw.WindowHint(glfw.OpenglProfile, glfw.OpenglCoreProfile)
	glfw.WindowHint(glfw.OpenglForwardCompatible, glfw.True) // needed for macs

	window, err := glfw.CreateWindow(1024, 768, "Tutorial 1", nil, nil)
	if err != nil {
		fmt.Fprintf(os.Stderr, "%v\n", err)
		return
	}

	window.MakeContextCurrent()

	gl.Init()
	gl.GetError() // Ignore error
	window.SetInputMode(glfw.StickyKeys, 1)

	gl.ClearColor(0., 0., 0.4, 0.)
	// Equivalent to a do... while
	for ok := true; ok; ok = (window.GetKey(glfw.KeyEscape) != glfw.Press && !window.ShouldClose()) {
		window.SwapBuffers()
		glfw.PollEvents()
	}

}

func RunIn3DContext(example func()) {
	if !glfw.Init() {
		log.Panic("glfw Error")
	}
	defer glfw.Terminate()

	glfw.WindowHint(glfw.ContextVersionMajor, 3)
	glfw.WindowHint(glfw.ContextVersionMinor, 3)
	glfw.WindowHint(glfw.OpenglForwardCompatible, glfw.True)
	glfw.WindowHint(glfw.OpenglProfile, glfw.OpenglCoreProfile)

	w, h := 100, 100
	window, err := glfw.CreateWindow(w, h, "Test", nil, nil)
	if err != nil {
		log.Panic(err)
	}
	window.MakeContextCurrent()

	if gl.Init() != 0 {
		log.Panic("gl error")
	}
	gl.GetError()

	vertexArray := gl.GenVertexArray()
	vertexArray.Bind()

	example()
}

func init() {
	go func() {
		runtime.LockOSThread()

		if err := glfw.Init(); err != nil {
			log.Panic("glfw Error:", err)
		}

		w, h := 100, 100
		err := glfw.OpenWindow(w, h, 0, 0, 0, 0, 0, 0, glfw.Windowed)
		if err != nil {
			log.Panic("Error:", err)
		}

		if gl.Init() != 0 {
			log.Panic("gl error")
		}

		glfw.SetWindowSizeCallback(Reshape)
		glfw.SwapBuffers()

		for {
			(<-main_thread_setup)()
			glfw.SwapBuffers()
			(<-main_thread_after)()
			main_thread_work_done <- true
		}
	}()
}

// 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 main() {

	if !glfw.Init() {
		log.Fatal("glfw failed to initialize")
	}
	defer glfw.Terminate()

	window, err := glfw.CreateWindow(640, 480, "Deformable", nil, nil)
	if err != nil {
		log.Fatal(err.Error())
	}

	window.MakeContextCurrent()
	glfw.SwapInterval(1)
	window.SetMouseButtonCallback(handleMouseButton)
	window.SetKeyCallback(handleKeyDown)
	window.SetInputMode(glfw.Cursor, glfw.CursorHidden)

	gl.Init()
	initGL()

	i := 16
	m = GenerateMap(1600/i, 1200/i, i)
	for running && !window.ShouldClose() {

		x, y := window.GetCursorPosition()

		if drawing != 0 {
			m.Add(int(x)+int(camera[0]), int(y)+int(camera[1]), drawing, brushSizes[currentBrushSize])
		}

		gl.Clear(gl.COLOR_BUFFER_BIT)
		gl.LoadIdentity()

		gl.PushMatrix()
		gl.PushAttrib(gl.CURRENT_BIT | gl.ENABLE_BIT | gl.LIGHTING_BIT | gl.POLYGON_BIT | gl.LINE_BIT)
		gl.Translatef(-camera[0], -camera[1], 0)
		m.Draw()
		gl.PopAttrib()
		gl.PopMatrix()

		gl.PushAttrib(gl.COLOR_BUFFER_BIT)
		gl.LineWidth(2)
		gl.Enable(gl.BLEND)
		gl.BlendFunc(gl.ONE_MINUS_DST_COLOR, gl.ZERO)
		// gl.Enable(gl.LINE_SMOOTH)
		// gl.Hint(gl.LINE_SMOOTH_HINT, gl.NICEST)

		gl.Translatef(float32(x), float32(y), 0)

		gl.EnableClientState(gl.VERTEX_ARRAY)
		gl.VertexPointer(2, gl.DOUBLE, 0, cursorVerts)
		gl.DrawArrays(gl.LINE_LOOP, 0, 24)
		gl.PopAttrib()

		window.SwapBuffers()
		glfw.PollEvents()
	}

}