canvas/backend/software/fill.go
2019-05-12 13:06:23 +02:00

56 lines
1 KiB
Go

package softwarebackend
import (
"image/color"
"github.com/tfriedel6/canvas/backend/backendbase"
)
func (b *SoftwareBackend) Clear(pts [4][2]float64) {
iterateTriangles(pts[:], func(tri [][2]float64) {
b.fillTriangle(tri, func(x, y int) {
if b.clip.AlphaAt(x, y).A == 0 {
return
}
b.Image.SetRGBA(x, y, color.RGBA{})
})
})
}
func (b *SoftwareBackend) Fill(style *backendbase.FillStyle, pts [][2]float64) {
iterateTriangles(pts[:], func(tri [][2]float64) {
b.fillTriangle(tri, func(x, y int) {
if b.clip.AlphaAt(x, y).A == 0 {
return
}
b.Image.SetRGBA(x, y, style.Color)
})
})
}
func (b *SoftwareBackend) ClearClip() {
p := b.clip.Pix
for i := range p {
p[i] = 255
}
}
func (b *SoftwareBackend) Clip(pts [][2]float64) {
p2 := b.clip2.Pix
for i := range p2 {
p2[i] = 0
}
iterateTriangles(pts[:], func(tri [][2]float64) {
b.fillTriangle(tri, func(x, y int) {
b.clip2.SetAlpha(x, y, color.Alpha{A: 255})
})
})
p := b.clip.Pix
for i := range p {
if p2[i] == 0 {
p[i] = 0
}
}
}