func main() { sdl.Init(sdl.INIT_VIDEO) sdl.SetVideoMode(800, 600, 32, sdl.OPENGL|sdl.DOUBLEBUF|sdl.HWSURFACE) gl.Init() gl.Enable(gl.DEPTH_TEST) gl.Viewport(0, 0, 800, 600) tick := time.Tick(time.Second / 50) timer := 0.0 posbuf := gl.NewBuffer(gl.ARRAY_BUFFER, Vertices, gl.STATIC_DRAW) prog, err := gl.MakeProgram([]string{vertexShader}, []string{fragmentShader}) if err != nil { fmt.Println(err) return } f, err := os.Open("glenda.png") if err != nil { fmt.Println(err) return } img, _, err := image.Decode(f) if err != nil { fmt.Println(err) return } tex := gl.NewTexture2D(img, 0) for { select { case ev := <-sdl.Events: if _, ok := ev.(sdl.QuitEvent); ok { return } case <-tick: gl.ClearColor(0, 0, 0, 1) gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT) prog.Use() mat := gl.Mul4(gl.Frustum(45, 800./600, 0.01, 100), gl.Translate(0, 0, -8), gl.RotX(timer), gl.RotY(2*timer), gl.RotZ(3*timer)) prog.EnableAttrib("position", posbuf, 0, 3, 5, false) prog.EnableAttrib("texcoord", posbuf, 3, 2, 5, false) prog.SetUniform("tex", 0) prog.SetUniform("matrix", mat) tex.Enable(0, gl.TEXTURE_2D) gl.DrawArrays(gl.TRIANGLE_STRIP, 0, len(Vertices)/5) prog.DisableAttrib("position") prog.Unuse() sdl.GL_SwapBuffers() timer += 1 } } }
func Quad(cx, cy, d, r float64, tex string) { t, ok := texs[tex] if !ok { panic("no such texture " + tex) } prog.Use() prog.EnableAttrib("pos", quadBuf, 0, 2, 0, false) t.Enable(0, gl.TEXTURE_2D) prog.SetUniform("matrix", gl.Mul4(winscale, gl.Translate(cx-d/2, cy-d/2, 0), gl.Scale(d, d, 1), gl.Translate(0.5, 0.5, 0), gl.RotZ(r), gl.Translate(-0.5, -0.5, 0))) prog.SetUniform("tex", 0) gl.DrawArrays(gl.TRIANGLE_STRIP, 0, 4) prog.DisableAttrib("pos") prog.Unuse() }