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arcs are now marked as convex to optimize performance

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This commit is contained in:
Thomas Friedel 2018-04-04 17:12:57 +02:00
parent 8502818b6f
commit 3854f40898
1 changed files with 29 additions and 8 deletions
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37
paths.go
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@ -18,6 +18,7 @@ const (
pathMove pathPointFlag = 1 << iota pathMove pathPointFlag = 1 << iota
pathAttach pathAttach
pathIsRect pathIsRect
pathIsConvex
) )
func (cv *Canvas) BeginPath() { func (cv *Canvas) BeginPath() {
@ -113,6 +114,9 @@ func (cv *Canvas) fillLineTo(x, y float64) {
} }
func (cv *Canvas) Arc(x, y, radius, startAngle, endAngle float64, anticlockwise bool) { func (cv *Canvas) Arc(x, y, radius, startAngle, endAngle float64, anticlockwise bool) {
lastLineWasMove := len(cv.linePath) == 0 || cv.linePath[len(cv.linePath)-1].flags&pathMove != 0
lastPolyWasMove := len(cv.polyPath) == 0 || cv.polyPath[len(cv.polyPath)-1].flags&pathMove != 0
startAngle = math.Mod(startAngle, math.Pi*2) startAngle = math.Mod(startAngle, math.Pi*2)
if startAngle < 0 { if startAngle < 0 {
startAngle += math.Pi * 2 startAngle += math.Pi * 2
@ -146,6 +150,13 @@ func (cv *Canvas) Arc(x, y, radius, startAngle, endAngle float64, anticlockwise
} }
s, c := math.Sincos(endAngle) s, c := math.Sincos(endAngle)
cv.LineTo(x+radius*c, y+radius*s) cv.LineTo(x+radius*c, y+radius*s)
if lastLineWasMove {
cv.linePath[len(cv.linePath)-1].flags |= pathIsConvex
}
if lastPolyWasMove {
cv.polyPath[len(cv.polyPath)-1].flags |= pathIsConvex
}
} }
func (cv *Canvas) ArcTo(x1, y1, x2, y2, radius float64) { func (cv *Canvas) ArcTo(x1, y1, x2, y2, radius float64) {
@ -460,29 +471,39 @@ func (cv *Canvas) Fill() {
continue continue
} }
if i >= start+3 { if i >= start+3 {
cv.fillPoly(start, i) cv.fillPoly(cv.polyPath[start:i])
} }
start = i start = i
} }
if len(cv.polyPath) >= start+3 { if len(cv.polyPath) >= start+3 {
cv.fillPoly(start, len(cv.polyPath)) cv.fillPoly(cv.polyPath[start:])
} }
} }
func (cv *Canvas) fillPoly(from, to int) { func (cv *Canvas) fillPoly(path []pathPoint) {
path := cv.polyPath[from:to]
if len(path) < 3 { if len(path) < 3 {
return return
} }
path = cv.cutIntersections(path)
cv.activate() cv.activate()
gli.BindBuffer(gl_ARRAY_BUFFER, buf) gli.BindBuffer(gl_ARRAY_BUFFER, buf)
var triBuf [1000]float32 var triBuf [1000]float32
tris := triangulatePath(path, triBuf[:0]) var tris []float32
if len(tris) == 0 { if path[len(path)-1].flags&pathIsConvex != 0 {
return p0, p1 := path[0].tf, path[1].tf
last := len(path)
for i := 2; i < last; i++ {
p2 := path[i].tf
tris = append(tris, float32(p0[0]), float32(p0[1]), float32(p1[0]), float32(p1[1]), float32(p2[0]), float32(p2[1]))
p1 = p2
}
} else {
path = cv.cutIntersections(path)
tris = triangulatePath(path, triBuf[:0])
if len(tris) == 0 {
return
}
} }
gli.BufferData(gl_ARRAY_BUFFER, len(tris)*4, unsafe.Pointer(&tris[0]), gl_STREAM_DRAW) gli.BufferData(gl_ARRAY_BUFFER, len(tris)*4, unsafe.Pointer(&tris[0]), gl_STREAM_DRAW)