func handleCursor(screen *ebiten.Image) error {
mx, my := ebiten.CursorPosition()
cursorMoved := image.Point{mx, my}.In(screen.Bounds()) && (mx != oldMouseCursorPosition.X || my != oldMouseCursorPosition.Y)
oldMouseCursorPosition = image.Point{mx, my}
if cursorMoved {
cursorPosition = oldMouseCursorPosition
} else {
const cursorInterval = 6
switch {
case keyStates[ebiten.KeyUp]%cursorInterval == 0:
cursorPosition = cursorPosition.Add(image.Point{0, -1})
cursorMoved = true
case keyStates[ebiten.KeyDown]%cursorInterval == 0:
cursorPosition = cursorPosition.Add(image.Point{0, +1})
cursorMoved = true
case keyStates[ebiten.KeyLeft]%cursorInterval == 0:
cursorPosition = cursorPosition.Add(image.Point{-1, 0})
cursorMoved = true
case keyStates[ebiten.KeyRight]%cursorInterval == 0:
cursorPosition = cursorPosition.Add(image.Point{+1, 0})
cursorMoved = true
}
}
if cursorBlinking == 127 {
cursorBlinking = 0
} else {
cursorBlinking++
}
op := &ebiten.DrawImageOptions{}
op.GeoM.Scale(0.25, .25)
op.GeoM.Translate(float64(cursorPosition.X), float64(cursorPosition.Y))
if cursorBlinking > 64 {
op.ColorM.Scale(1, 1, 1, 0.25+float64(127-cursorBlinking)/255.0)
} else {
op.ColorM.Scale(1, 1, 1, 0.25+float64(cursorBlinking)/255.0)
}
if err := screen.DrawImage(cursorImage, op); err != nil {
return err
}
if keyStates[ebiten.KeySpace] >= 0 ||
ebiten.IsMouseButtonPressed(ebiten.MouseButtonLeft) {
if cursorMoved || !wasMouseButtonPressed {
if err := togglePixel(cursorPosition); err != nil {
return err
}
wasMouseButtonPressed = true
}
} else {
wasMouseButtonPressed = false
}
return nil
}
func (r *recorder) update(screen *ebiten.Image) error {
if err := r.inner(screen); err != nil {
return err
}
if r.currentFrame == r.frameNum {
return nil
}
if r.currentFrame%r.skips == 0 {
if r.gif == nil {
num := (r.frameNum-1)/r.skips + 1
r.gif = &gif.GIF{
Image: make([]*image.Paletted, num),
Delay: make([]int, num),
LoopCount: -1,
}
}
s := image.NewNRGBA(screen.Bounds())
draw.Draw(s, s.Bounds(), screen, screen.Bounds().Min, draw.Src)
img := image.NewPaletted(s.Bounds(), r.palette())
f := r.currentFrame / r.skips
r.wg.Add(1)
go func() {
defer r.wg.Done()
draw.FloydSteinberg.Draw(img, img.Bounds(), s, s.Bounds().Min)
r.gif.Image[f] = img
r.gif.Delay[f] = r.delay()
}()
}
r.currentFrame++
if r.currentFrame == r.frameNum {
r.wg.Wait()
if err := gif.EncodeAll(r.writer, r.gif); err != nil {
return err
}
}
return nil
}