examples/alphablending: Refactoring: Reduce draw calls

This commit is contained in:
Hajime Hoshi 2016-04-23 01:34:02 +09:00
parent a2689b8b8c
commit 5a1099db27

View File

@ -29,11 +29,30 @@ const (
)
var (
count int
tmpRenderTarget *ebiten.Image
ebitenImage *ebiten.Image
count int
ebitenImage *ebiten.Image
)
type imageParts struct {
diff float64
}
func (p *imageParts) Src(i int) (int, int, int, int) {
w, h := ebitenImage.Size()
return 0, 0, w, h
}
func (p *imageParts) Dst(i int) (int, int, int, int) {
x := int(float64(i%10)*p.diff + 15)
y := int(float64(i/10)*p.diff + 20)
w, h := ebitenImage.Size()
return x, y, x + w, y + h
}
func (p *imageParts) Len() int {
return 10 * 10
}
func update(screen *ebiten.Image) error {
count++
count %= ebiten.FPS * 10
@ -45,27 +64,15 @@ func update(screen *ebiten.Image) error {
diff = float64(480-count) * 0.2
}
if err := tmpRenderTarget.Clear(); err != nil {
screen.Fill(color.NRGBA{0x00, 0x00, 0x80, 0xff})
op := &ebiten.DrawImageOptions{}
op.ColorM.Scale(1.0, 1.0, 1.0, 0.5)
op.ImageParts = &imageParts{
diff: diff,
}
if err := screen.DrawImage(ebitenImage, op); err != nil {
return err
}
for i := 0; i < 10; i++ {
op := &ebiten.DrawImageOptions{}
op.GeoM.Translate(15+float64(i)*diff, 20)
op.ColorM.Scale(1.0, 1.0, 1.0, 0.5)
if err := tmpRenderTarget.DrawImage(ebitenImage, op); err != nil {
return err
}
}
screen.Fill(color.NRGBA{0x00, 0x00, 0x80, 0xff})
for i := 0; i < 10; i++ {
op := &ebiten.DrawImageOptions{}
op.GeoM.Translate(0, float64(i)*diff)
if err := screen.DrawImage(tmpRenderTarget, op); err != nil {
return err
}
}
return nil
}
@ -75,10 +82,6 @@ func main() {
if err != nil {
log.Fatal(err)
}
tmpRenderTarget, err = ebiten.NewImage(screenWidth, screenHeight, ebiten.FilterNearest)
if err != nil {
log.Fatal(err)
}
if err := ebiten.Run(update, screenWidth, screenHeight, 2, "Alpha Blending (Ebiten Demo)"); err != nil {
log.Fatal(err)
}