func (c *Context) SetViewport(f Framebuffer, width, height int) error {
gl.Flush()
gl.BindFramebuffer(gl.FRAMEBUFFER, uint32(f))
if err := gl.CheckFramebufferStatus(gl.FRAMEBUFFER); err != gl.FRAMEBUFFER_COMPLETE {
if e := gl.GetError(); e != 0 {
return errors.New(fmt.Sprintf("glBindFramebuffer failed: %d", e))
}
return errors.New("glBindFramebuffer failed: the context is different?")
}
gl.Viewport(0, 0, int32(width), int32(height))
return nil
}
func (c *Context) FramebufferPixels(f Framebuffer, width, height int) ([]uint8, error) {
gl.Flush()
gl.BindFramebuffer(gl.FRAMEBUFFER, uint32(f))
pixels := make([]uint8, 4*width*height)
gl.ReadPixels(0, 0, int32(width), int32(height), gl.RGBA, gl.UNSIGNED_BYTE, gl.Ptr(pixels))
if e := gl.GetError(); e != gl.NO_ERROR {
return nil, errors.New(fmt.Sprintf("glReadPixels: %d", e))
}
return pixels, nil
}
func display() {
gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT)
gl.LineWidth(1)
gc := draw2dgl.NewGraphicContext(width, height)
gc.SetFontData(draw2d.FontData{
Name: "luxi",
Family: draw2d.FontFamilyMono,
Style: draw2d.FontStyleBold | draw2d.FontStyleItalic})
gc.BeginPath()
draw2dkit.RoundedRectangle(gc, 200, 200, 600, 600, 100, 100)
gc.SetFillColor(color.RGBA{0, 0, 0, 0xff})
gc.Fill()
gl.Flush() /* Single buffered, so needs a flush. */
}
func display() {
gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT)
lastTime := time.Now()
gl.LineWidth(1)
gc := draw2dgl.NewGraphicContext(width, height)
gc.Translate(380, 400)
gc.Scale(1, -1)
rotate = (rotate + 1) % 360
gc.Rotate(float64(rotate) * math.Pi / 180)
gc.Translate(-380, -400)
interpreter := ps.NewInterpreter(gc)
reader := strings.NewReader(postscriptContent)
interpreter.Execute(reader)
dt := time.Now().Sub(lastTime)
log.Printf("Redraw in : %f ms\n", float64(dt)*1e-6)
gl.Flush() /* Single buffered, so needs a flush. */
}
func (c *Context) FramebufferPixels(f Framebuffer, width, height int) ([]uint8, error) {
var pixels []uint8
if err := c.runOnContextThread(func() error {
gl.Flush()
return nil
}); err != nil {
return nil, err
}
if err := c.bindFramebuffer(f); err != nil {
return nil, err
}
if err := c.runOnContextThread(func() error {
pixels = make([]uint8, 4*width*height)
gl.ReadPixels(0, 0, int32(width), int32(height), gl.RGBA, gl.UNSIGNED_BYTE, gl.Ptr(pixels))
if e := gl.GetError(); e != gl.NO_ERROR {
pixels = nil
return fmt.Errorf("opengl: glReadPixels: %d", e)
}
return nil
}); err != nil {
return nil, err
}
return pixels, nil
}
// Flush empties all buffers. It does not block.
//
// An OpenGL implementation may buffer network communication,
// the command stream, or data inside the graphics accelerator.
//
// http://www.khronos.org/opengles/sdk/docs/man3/html/glFlush.xhtml
func Flush() {
gl.Flush()
}
func (w *Window) Show() {
if err := glfw.Init(); err != nil {
log.Fatalln("failed to initialize glfw:", err)
}
defer glfw.Terminate()
glfw.WindowHint(glfw.Resizable, glfw.False)
glfw.WindowHint(glfw.Resizable, glfw.True)
window, err := glfw.CreateWindow(w.W, w.H, w.Title, nil, nil)
if err != nil {
panic(err)
}
if err := gl.Init(); err != nil {
panic(err)
}
window.MakeContextCurrent()
if len(w.Icon) == 1 {
window.SetIcon(w.Icon)
}
if w.RestrictionsEnabled {
window.SetSizeLimits(w.MinW, w.MinH, w.MaxW, w.MaxH)
}
if w.Blend {
gl.Enable(gl.BLEND)
gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
} else if w.Smooth {
gl.Enable(gl.SMOOTH)
gl.Enable(gl.POINT_SMOOTH)
gl.Enable(gl.LINE_SMOOTH)
gl.Enable(gl.POLYGON_SMOOTH)
gl.Enable(gl.RELATIVE_SMOOTH_CUBIC_CURVE_TO_NV)
gl.Enable(gl.RELATIVE_SMOOTH_QUADRATIC_CURVE_TO_NV)
} else if w.Multisample {
gl.Enable(gl.MULTISAMPLE)
}
reshape(w.W, w.H)
window.SetRefreshCallback(func(g *glfw.Window) { reshape(w.W, w.H) })
window.SetSizeCallback(func(g *glfw.Window, width int, height int) {
reshape(width, height)
w.W = width
w.H = height
})
version := gl.GoStr(gl.GetString(gl.VERSION))
if !silentMode {
fmt.Println("OpenGL version", version)
}
for !window.ShouldClose() {
//Reset?
gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT)
if w.DrawFunc != nil {
w.DrawFunc()
}
// Maintenance
gl.Flush()
window.SwapBuffers()
glfw.PollEvents()
}
}
func (c *Context) Flush() {
_ = c.runOnContextThread(func() error {
gl.Flush()
return nil
})
}