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small improvements and fixes

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This commit is contained in:
Thomas Friedel 2018-02-11 16:50:50 +01:00
parent be6bd3a506
commit a3fc5eba89
1 changed files with 37 additions and 16 deletions
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53
paths.go
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@ -19,15 +19,30 @@ func (cv *Canvas) BeginPath() {
cv.polyPath = cv.polyPath[:0] cv.polyPath = cv.polyPath[:0]
} }
func isSamePoint(a, b lm.Vec2, maxDist float32) bool {
return fmath.Abs(b[0]-a[0]) <= maxDist && fmath.Abs(b[1]-a[1]) <= maxDist
}
func (cv *Canvas) MoveTo(x, y float32) { func (cv *Canvas) MoveTo(x, y float32) {
tf := cv.tf(lm.Vec2{x, y}) tf := cv.tf(lm.Vec2{x, y})
if len(cv.linePath) > 0 && isSamePoint(cv.linePath[len(cv.linePath)-1].tf, tf, 0.1) {
return
}
cv.linePath = append(cv.linePath, pathPoint{pos: lm.Vec2{x, y}, tf: tf, move: true}) cv.linePath = append(cv.linePath, pathPoint{pos: lm.Vec2{x, y}, tf: tf, move: true})
cv.polyPath = append(cv.polyPath, pathPoint{pos: lm.Vec2{x, y}, tf: tf, move: true}) cv.polyPath = append(cv.polyPath, pathPoint{pos: lm.Vec2{x, y}, tf: tf, move: true})
} }
func (cv *Canvas) LineTo(x, y float32) { func (cv *Canvas) LineTo(x, y float32) {
cv.strokeLineTo(x, y)
cv.fillLineTo(x, y)
}
func (cv *Canvas) strokeLineTo(x, y float32) {
if len(cv.linePath) > 0 && isSamePoint(cv.linePath[len(cv.linePath)-1].tf, cv.tf(lm.Vec2{x, y}), 0.1) {
return
}
if len(cv.linePath) == 0 { if len(cv.linePath) == 0 {
cv.MoveTo(x, y) cv.linePath = append(cv.linePath, pathPoint{pos: lm.Vec2{x, y}, tf: cv.tf(lm.Vec2{x, y}), move: true})
return return
} }
if len(cv.state.lineDash) > 0 { if len(cv.state.lineDash) > 0 {
@ -69,6 +84,16 @@ func (cv *Canvas) LineTo(x, y float32) {
cv.linePath[len(cv.linePath)-1].attach = true cv.linePath[len(cv.linePath)-1].attach = true
cv.linePath = append(cv.linePath, pathPoint{pos: lm.Vec2{x, y}, tf: tf, move: false}) cv.linePath = append(cv.linePath, pathPoint{pos: lm.Vec2{x, y}, tf: tf, move: false})
} }
}
func (cv *Canvas) fillLineTo(x, y float32) {
if len(cv.polyPath) > 0 && isSamePoint(cv.polyPath[len(cv.polyPath)-1].tf, cv.tf(lm.Vec2{x, y}), 0.1) {
return
}
if len(cv.polyPath) == 0 {
cv.polyPath = append(cv.polyPath, pathPoint{pos: lm.Vec2{x, y}, tf: cv.tf(lm.Vec2{x, y}), move: true})
return
}
tf := cv.tf(lm.Vec2{x, y}) tf := cv.tf(lm.Vec2{x, y})
cv.polyPath[len(cv.polyPath)-1].next = tf cv.polyPath[len(cv.polyPath)-1].next = tf
cv.polyPath[len(cv.polyPath)-1].attach = true cv.polyPath[len(cv.polyPath)-1].attach = true
@ -140,16 +165,12 @@ func (cv *Canvas) ClosePath() {
if len(cv.linePath) < 2 { if len(cv.linePath) < 2 {
return return
} }
if len(cv.state.lineDash) > 0 { if isSamePoint(cv.linePath[len(cv.linePath)-1].tf, cv.linePath[0].tf, 0.1) {
cv.LineTo(cv.linePath[0].pos[0], cv.linePath[0].pos[1])
return return
} }
cv.linePath[len(cv.linePath)-1].next = cv.linePath[0].pos cv.LineTo(cv.linePath[0].pos[0], cv.linePath[0].pos[1])
cv.linePath[len(cv.linePath)-1].attach = true cv.linePath[len(cv.linePath)-1].next = cv.linePath[0].tf
cv.linePath = append(cv.linePath, pathPoint{pos: cv.linePath[0].pos, move: false, tf: cv.linePath[0].tf, next: cv.linePath[1].pos, attach: true}) cv.polyPath[len(cv.polyPath)-1].next = cv.polyPath[0].tf
cv.polyPath[len(cv.polyPath)-1].next = cv.polyPath[0].pos
cv.polyPath[len(cv.polyPath)-1].attach = true
cv.polyPath = append(cv.polyPath, pathPoint{pos: cv.polyPath[0].pos, move: false, tf: cv.linePath[0].tf, next: cv.polyPath[1].pos, attach: true})
} }
func (cv *Canvas) Stroke() { func (cv *Canvas) Stroke() {
@ -268,8 +289,8 @@ func (cv *Canvas) lineJoint(p pathPoint, p0, p1, p2, l0p0, l0p1, l0p2, l0p3 lm.V
l1p2 := p2.Add(v3) l1p2 := p2.Add(v3)
l1p3 := p1.Add(v3) l1p3 := p1.Add(v3)
ip0 := lineIntersection(l0p0, l0p1, l1p1, l1p0) ip0, _ := lineIntersection(l0p0, l0p1, l1p1, l1p0)
ip1 := lineIntersection(l0p2, l0p3, l1p3, l1p2) ip1, _ := lineIntersection(l0p2, l0p3, l1p3, l1p2)
tris = append(tris, tris = append(tris,
p1[0], p1[1], l0p1[0], l0p1[1], ip0[0], ip0[1], p1[0], p1[1], l0p1[0], l0p1[1], ip0[0], ip0[1],
@ -307,17 +328,17 @@ func (cv *Canvas) addCircleTris(center lm.Vec2, radius float32, tris []float32)
return tris return tris
} }
func lineIntersection(a0, a1, b0, b1 lm.Vec2) lm.Vec2 { func lineIntersection(a0, a1, b0, b1 lm.Vec2) (lm.Vec2, float32) {
va := a1.Sub(a0) va := a1.Sub(a0)
vb := b1.Sub(b0) vb := b1.Sub(b0)
if vb[1] == 0 { if vb[1] == 0 {
q := (a0[0] + (b0[1]-a0[1])*(va[0]/va[1]) - b0[0]) / (vb[0] - vb[1]*(va[0]/va[1])) r := (b0[1] + (a0[0]-b0[0])*(vb[1]/vb[0]) - a0[1]) / (va[1] - va[0]*(vb[1]/vb[0]))
return b0.Add(vb.MulF(q)) return a0.Add(va.MulF(r)), r
} }
p := (b0[0] + (a0[1]-b0[1])*(vb[0]/vb[1]) - a0[0]) / (va[0] - va[1]*(vb[0]/vb[1])) r := (b0[0] + (a0[1]-b0[1])*(vb[0]/vb[1]) - a0[0]) / (va[0] - va[1]*(vb[0]/vb[1]))
return a0.Add(va.MulF(p)) return a0.Add(va.MulF(r)), r
} }
func (cv *Canvas) Fill() { func (cv *Canvas) Fill() {