Example #1
0
// InitGraphics creates an OpenGL window and initializes the required graphics libraries.
// It will either succeed or panic.
func (app *ExampleApp) InitGraphics(title string, w int, h int) {
	err := glfw.Init()
	if err != nil {
		panic("Can't init glfw! " + err.Error())
	}

	// request a OpenGL 3.3 core context
	glfw.WindowHint(glfw.Samples, 0)
	glfw.WindowHint(glfw.ContextVersionMajor, 3)
	glfw.WindowHint(glfw.ContextVersionMinor, 3)
	glfw.WindowHint(glfw.OpenGLForwardCompatible, glfw.True)
	glfw.WindowHint(glfw.OpenGLProfile, glfw.OpenGLCoreProfile)

	// do the actual window creation
	app.MainWindow, err = glfw.CreateWindow(w, h, title, nil, nil)
	if err != nil {
		panic("Failed to create the main window! " + err.Error())
	}
	app.MainWindow.MakeContextCurrent()
	glfw.SwapInterval(0)

	// make sure that all of the GL functions are initialized
	err = gl.Init()
	if err != nil {
		panic("Failed to initialize GL! " + err.Error())
	}

	// set the app window dimensions
	app.Width = w
	app.Height = h

	gl.FrontFace(gl.CCW)
	gl.CullFace(gl.BACK)
	gl.Enable(gl.CULL_FACE)
}
Example #2
0
func InitGL() error {
	defer tlog.FuncLog(tlog.Func("InitGL"))

	err := gl.Init()
	if err != nil {
		return err
	}
	gl.GetError() // cleanup gl error state

	version := gl.GoStr(gl.GetString(gl.VERSION))
	tlog.Println("OpenGL version", version)

	gl.PolygonMode(gl.FRONT_AND_BACK, gl.FILL)
	Check()
	gl.ReadBuffer(gl.BACK)
	Check()
	gl.DrawBuffer(gl.BACK)
	Check()

	gl.FrontFace(gl.CW)
	Check()
	gl.CullFace(gl.BACK)
	Check()
	gl.Disable(gl.CULL_FACE)
	Check()

	gl.ClearColor(1, 1, 0.5, 0)
	Check()
	gl.ClearDepth(1.0)
	Check()
	gl.ClearStencil(0)
	Check()

	gl.Disable(gl.STENCIL_TEST)
	Check()
	gl.StencilMask(0xFFFFFFFF)
	Check()
	gl.StencilFunc(gl.EQUAL, 0x00000000, 0x00000001)
	Check()
	gl.StencilOp(gl.KEEP, gl.KEEP, gl.KEEP)
	Check()

	gl.Disable(gl.DITHER)
	Check()

	gl.Enable(gl.DEPTH_TEST)
	Check()
	gl.DepthFunc(gl.LEQUAL)
	Check()
	gl.DepthMask(true)
	Check()
	gl.DepthRange(0., 1.)
	Check()
	gl.Enable(gl.DEPTH_CLAMP)
	Check()

	gl.Enable(gl.BLEND)
	Check()
	gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)

	ForceCheck()
	return nil
}