Rename LineTracer and VertexConverter to LineBuilder

This commit is contained in:
Laurent Le Goff 2015-04-23 15:36:56 +02:00
parent 4b3ba53f4c
commit ceb331894d
16 changed files with 180 additions and 177 deletions

4
arc.go
View file

@ -9,7 +9,7 @@ import (
"code.google.com/p/freetype-go/freetype/raster"
)
func arc(t VertexConverter, x, y, rx, ry, start, angle, scale float64) (lastX, lastY float64) {
func arc(t LineBuilder, x, y, rx, ry, start, angle, scale float64) (lastX, lastY float64) {
end := start + angle
clockWise := true
if angle < 0 {
@ -33,7 +33,7 @@ func arc(t VertexConverter, x, y, rx, ry, start, angle, scale float64) (lastX, l
curY = y + math.Sin(angle)*ry
angle += da
t.AddPoint(curX, curY)
t.LineTo(curX, curY)
}
return curX, curY
}

View file

@ -7,8 +7,8 @@ import (
"math"
)
// TraceArc trace an arc using a LineTracer
func TraceArc(t LineTracer, x, y, rx, ry, start, angle, scale float64) {
// TraceArc trace an arc using a LineBuilder
func TraceArc(t LineBuilder, x, y, rx, ry, start, angle, scale float64) {
end := start + angle
clockWise := true
if angle < 0 {
@ -32,7 +32,7 @@ func TraceArc(t LineTracer, x, y, rx, ry, start, angle, scale float64) {
curY = y + math.Sin(angle)*ry
angle += da
t.AddPoint(curX, curY)
t.LineTo(curX, curY)
}
t.AddPoint(curX, curY)
t.LineTo(curX, curY)
}

View file

@ -46,9 +46,9 @@ func SubdivideCubic(c, c1, c2 []float64) {
c2[0], c2[1] = c1[6], c1[7]
}
// TraceCubic generate lines subdividing the cubic curve using a LineTracer
// TraceCubic generate lines subdividing the cubic curve using a LineBuilder
// flattening_threshold helps determines the flattening expectation of the curve
func TraceCubic(t LineTracer, cubic []float64, flattening_threshold float64) {
func TraceCubic(t LineBuilder, cubic []float64, flattening_threshold float64) {
// Allocation curves
var curves [CurveRecursionLimit * 8]float64
copy(curves[0:8], cubic[0:8])
@ -69,7 +69,7 @@ func TraceCubic(t LineTracer, cubic []float64, flattening_threshold float64) {
// if it's flat then trace a line
if (d2+d3)*(d2+d3) < flattening_threshold*(dx*dx+dy*dy) || i == len(curves)-1 {
t.AddPoint(c[6], c[7])
t.LineTo(c[6], c[7])
i--
} else {
// second half of bezier go lower onto the stack

View file

@ -38,7 +38,11 @@ type Path struct {
points []float64
}
func (p *Path) AddPoint(x, y float64) {
func (p *Path) MoveTo(x, y float64) {
p.points = append(p.points, x, y)
}
func (p *Path) LineTo(x, y float64) {
p.points = append(p.points, x, y)
}
@ -82,7 +86,7 @@ func drawPoints(img draw.Image, c color.Color, s ...float64) image.Image {
func TestCubicCurve(t *testing.T) {
for i := 0; i < len(testsCubicFloat64); i += 8 {
var p Path
p.AddPoint(testsCubicFloat64[i], testsCubicFloat64[i+1])
p.MoveTo(testsCubicFloat64[i], testsCubicFloat64[i+1])
TraceCubic(&p, testsCubicFloat64[i:], flattening_threshold)
img := image.NewNRGBA(image.Rect(0, 0, 300, 300))
raster.PolylineBresenham(img, color.NRGBA{0xff, 0, 0, 0xff}, testsCubicFloat64[i:i+8]...)
@ -98,7 +102,7 @@ func TestCubicCurve(t *testing.T) {
func TestQuadCurve(t *testing.T) {
for i := 0; i < len(testsQuadFloat64); i += 6 {
var p Path
p.AddPoint(testsQuadFloat64[i], testsQuadFloat64[i+1])
p.MoveTo(testsQuadFloat64[i], testsQuadFloat64[i+1])
TraceQuad(&p, testsQuadFloat64[i:], flattening_threshold)
img := image.NewNRGBA(image.Rect(0, 0, 300, 300))
raster.PolylineBresenham(img, color.NRGBA{0xff, 0, 0, 0xff}, testsQuadFloat64[i:i+6]...)
@ -115,7 +119,7 @@ func BenchmarkCubicCurve(b *testing.B) {
for i := 0; i < b.N; i++ {
for i := 0; i < len(testsCubicFloat64); i += 8 {
var p Path
p.AddPoint(testsCubicFloat64[i], testsCubicFloat64[i+1])
p.MoveTo(testsCubicFloat64[i], testsCubicFloat64[i+1])
TraceCubic(&p, testsCubicFloat64[i:], flattening_threshold)
}
}

7
curve/line.go Normal file
View file

@ -0,0 +1,7 @@
package curve
// LineBuilder is an interface that help segmenting curve into small lines
type LineBuilder interface {
// LineTo a point
LineTo(x, y float64)
}

View file

@ -29,9 +29,9 @@ func SubdivideQuad(c, c1, c2 []float64) {
return
}
// Trace generate lines subdividing the curve using a LineTracer
// Trace generate lines subdividing the curve using a LineBuilder
// flattening_threshold helps determines the flattening expectation of the curve
func TraceQuad(t LineTracer, quad []float64, flattening_threshold float64) {
func TraceQuad(t LineBuilder, quad []float64, flattening_threshold float64) {
// Allocates curves stack
var curves [CurveRecursionLimit * 6]float64
copy(curves[0:6], quad[0:6])
@ -49,7 +49,7 @@ func TraceQuad(t LineTracer, quad []float64, flattening_threshold float64) {
// if it's flat then trace a line
if (d*d) < flattening_threshold*(dx*dx+dy*dy) || i == len(curves)-1 {
t.AddPoint(c[4], c[5])
t.LineTo(c[4], c[5])
i--
} else {
// second half of bezier go lower onto the stack

View file

@ -1,7 +0,0 @@
package curve
// LineTracer is an interface that help segmenting curve into small lines
type LineTracer interface {
// AddPoint a point
AddPoint(x, y float64)
}

View file

@ -33,7 +33,7 @@ var (
The more this value is the less sharp turns will be cut.
Typically it should not exceed 10-15 degrees.
*/
func cubicBezier(v VertexConverter, x1, y1, x2, y2, x3, y3, x4, y4, approximationScale, angleTolerance, cuspLimit float64) {
func cubicBezier(v LineBuilder, x1, y1, x2, y2, x3, y3, x4, y4, approximationScale, angleTolerance, cuspLimit float64) {
cuspLimit = computeCuspLimit(cuspLimit)
distanceToleranceSquare := 0.5 / approximationScale
distanceToleranceSquare = distanceToleranceSquare * distanceToleranceSquare
@ -43,7 +43,7 @@ func cubicBezier(v VertexConverter, x1, y1, x2, y2, x3, y3, x4, y4, approximatio
/*
* see cubicBezier comments for approximationScale and angleTolerance definition
*/
func quadraticBezier(v VertexConverter, x1, y1, x2, y2, x3, y3, approximationScale, angleTolerance float64) {
func quadraticBezier(v LineBuilder, x1, y1, x2, y2, x3, y3, approximationScale, angleTolerance float64) {
distanceToleranceSquare := 0.5 / approximationScale
distanceToleranceSquare = distanceToleranceSquare * distanceToleranceSquare
@ -62,7 +62,7 @@ func computeCuspLimit(v float64) (r float64) {
/**
* http://www.antigrain.com/research/adaptive_bezier/index.html
*/
func recursiveQuadraticBezierBezier(v VertexConverter, x1, y1, x2, y2, x3, y3 float64, level int, distanceToleranceSquare, angleTolerance float64) {
func recursiveQuadraticBezierBezier(v LineBuilder, x1, y1, x2, y2, x3, y3 float64, level int, distanceToleranceSquare, angleTolerance float64) {
if level > CurveRecursionLimit {
return
}
@ -88,7 +88,7 @@ func recursiveQuadraticBezierBezier(v VertexConverter, x1, y1, x2, y2, x3, y3 fl
// we tend to finish subdivisions.
//----------------------
if angleTolerance < CurveAngleToleranceEpsilon {
v.AddPoint(x123, y123)
v.LineTo(x123, y123)
return
}
@ -102,7 +102,7 @@ func recursiveQuadraticBezierBezier(v VertexConverter, x1, y1, x2, y2, x3, y3 fl
if da < angleTolerance {
// Finally we can stop the recursion
//----------------------
v.AddPoint(x123, y123)
v.LineTo(x123, y123)
return
}
}
@ -128,7 +128,7 @@ func recursiveQuadraticBezierBezier(v VertexConverter, x1, y1, x2, y2, x3, y3 fl
}
}
if d < distanceToleranceSquare {
v.AddPoint(x2, y2)
v.LineTo(x2, y2)
return
}
}
@ -142,7 +142,7 @@ func recursiveQuadraticBezierBezier(v VertexConverter, x1, y1, x2, y2, x3, y3 fl
/**
* http://www.antigrain.com/research/adaptive_bezier/index.html
*/
func recursiveCubicBezier(v VertexConverter, x1, y1, x2, y2, x3, y3, x4, y4 float64, level int, distanceToleranceSquare, angleTolerance, cuspLimit float64) {
func recursiveCubicBezier(v LineBuilder, x1, y1, x2, y2, x3, y3, x4, y4 float64, level int, distanceToleranceSquare, angleTolerance, cuspLimit float64) {
if level > CurveRecursionLimit {
return
}
@ -209,12 +209,12 @@ func recursiveCubicBezier(v VertexConverter, x1, y1, x2, y2, x3, y3, x4, y4 floa
}
if d2 > d3 {
if d2 < distanceToleranceSquare {
v.AddPoint(x2, y2)
v.LineTo(x2, y2)
return
}
} else {
if d3 < distanceToleranceSquare {
v.AddPoint(x3, y3)
v.LineTo(x3, y3)
return
}
}
@ -225,7 +225,7 @@ func recursiveCubicBezier(v VertexConverter, x1, y1, x2, y2, x3, y3, x4, y4 floa
//----------------------
if d3*d3 <= distanceToleranceSquare*(dx*dx+dy*dy) {
if angleTolerance < CurveAngleToleranceEpsilon {
v.AddPoint(x23, y23)
v.LineTo(x23, y23)
return
}
@ -237,14 +237,14 @@ func recursiveCubicBezier(v VertexConverter, x1, y1, x2, y2, x3, y3, x4, y4 floa
}
if da1 < angleTolerance {
v.AddPoint(x2, y2)
v.AddPoint(x3, y3)
v.LineTo(x2, y2)
v.LineTo(x3, y3)
return
}
if cuspLimit != 0.0 {
if da1 > cuspLimit {
v.AddPoint(x3, y3)
v.LineTo(x3, y3)
return
}
}
@ -256,7 +256,7 @@ func recursiveCubicBezier(v VertexConverter, x1, y1, x2, y2, x3, y3, x4, y4 floa
//----------------------
if d2*d2 <= distanceToleranceSquare*(dx*dx+dy*dy) {
if angleTolerance < CurveAngleToleranceEpsilon {
v.AddPoint(x23, y23)
v.LineTo(x23, y23)
return
}
@ -268,14 +268,14 @@ func recursiveCubicBezier(v VertexConverter, x1, y1, x2, y2, x3, y3, x4, y4 floa
}
if da1 < angleTolerance {
v.AddPoint(x2, y2)
v.AddPoint(x3, y3)
v.LineTo(x2, y2)
v.LineTo(x3, y3)
return
}
if cuspLimit != 0.0 {
if da1 > cuspLimit {
v.AddPoint(x2, y2)
v.LineTo(x2, y2)
return
}
}
@ -290,7 +290,7 @@ func recursiveCubicBezier(v VertexConverter, x1, y1, x2, y2, x3, y3, x4, y4 floa
// we tend to finish subdivisions.
//----------------------
if angleTolerance < CurveAngleToleranceEpsilon {
v.AddPoint(x23, y23)
v.LineTo(x23, y23)
return
}
@ -309,18 +309,18 @@ func recursiveCubicBezier(v VertexConverter, x1, y1, x2, y2, x3, y3, x4, y4 floa
if da1+da2 < angleTolerance {
// Finally we can stop the recursion
//----------------------
v.AddPoint(x23, y23)
v.LineTo(x23, y23)
return
}
if cuspLimit != 0.0 {
if da1 > cuspLimit {
v.AddPoint(x2, y2)
v.LineTo(x2, y2)
return
}
if da2 > cuspLimit {
v.AddPoint(x3, y3)
v.LineTo(x3, y3)
return
}
}

View file

@ -4,15 +4,15 @@
package draw2d
type DashVertexConverter struct {
command VertexCommand
next VertexConverter
command LineMarker
next LineBuilder
x, y, distance float64
dash []float64
currentDash int
dashOffset float64
}
func NewDashConverter(dash []float64, dashOffset float64, converter VertexConverter) *DashVertexConverter {
func NewDashConverter(dash []float64, dashOffset float64, converter LineBuilder) *DashVertexConverter {
var dasher DashVertexConverter
dasher.dash = dash
dasher.currentDash = 0
@ -21,26 +21,20 @@ func NewDashConverter(dash []float64, dashOffset float64, converter VertexConver
return &dasher
}
func (dasher *DashVertexConverter) NextCommand(cmd VertexCommand) {
func (dasher *DashVertexConverter) NextCommand(cmd LineMarker) {
dasher.command = cmd
if dasher.command == VertexStopCommand {
dasher.next.NextCommand(VertexStopCommand)
if dasher.command == LineEndMarker {
dasher.next.NextCommand(LineEndMarker)
}
}
func (dasher *DashVertexConverter) AddPoint(x, y float64) {
switch dasher.command {
case VertexStartCommand:
dasher.start(x, y)
default:
func (dasher *DashVertexConverter) LineTo(x, y float64) {
dasher.lineTo(x, y)
}
dasher.command = VertexNoCommand
dasher.command = LineNoneMarker
}
func (dasher *DashVertexConverter) start(x, y float64) {
dasher.next.NextCommand(VertexStartCommand)
dasher.next.AddPoint(x, y)
func (dasher *DashVertexConverter) MoveTo(x, y float64) {
dasher.next.MoveTo(x, y)
dasher.x, dasher.y = x, y
dasher.distance = dasher.dashOffset
dasher.currentDash = 0
@ -60,12 +54,11 @@ func (dasher *DashVertexConverter) lineTo(x, y float64) {
ly := dasher.y + k*(y-dasher.y)
if dasher.currentDash%2 == 0 {
// line
dasher.next.AddPoint(lx, ly)
dasher.next.LineTo(lx, ly)
} else {
// gap
dasher.next.NextCommand(VertexStopCommand)
dasher.next.NextCommand(VertexStartCommand)
dasher.next.AddPoint(lx, ly)
dasher.next.NextCommand(LineEndMarker)
dasher.next.MoveTo(lx, ly)
}
d = d - rest
dasher.x, dasher.y = lx, ly
@ -75,12 +68,11 @@ func (dasher *DashVertexConverter) lineTo(x, y float64) {
dasher.distance = d
if dasher.currentDash%2 == 0 {
// line
dasher.next.AddPoint(x, y)
dasher.next.LineTo(x, y)
} else {
// gap
dasher.next.NextCommand(VertexStopCommand)
dasher.next.NextCommand(VertexStartCommand)
dasher.next.AddPoint(x, y)
dasher.next.NextCommand(LineEndMarker)
dasher.next.MoveTo(x, y)
}
if dasher.distance >= dasher.dash[dasher.currentDash] {
dasher.distance = dasher.distance - dasher.dash[dasher.currentDash]

View file

@ -4,20 +4,27 @@
package draw2d
type DemuxConverter struct {
converters []VertexConverter
converters []LineBuilder
}
func NewDemuxConverter(converters ...VertexConverter) *DemuxConverter {
func NewDemuxConverter(converters ...LineBuilder) *DemuxConverter {
return &DemuxConverter{converters}
}
func (dc *DemuxConverter) NextCommand(cmd VertexCommand) {
func (dc *DemuxConverter) NextCommand(cmd LineMarker) {
for _, converter := range dc.converters {
converter.NextCommand(cmd)
}
}
func (dc *DemuxConverter) AddPoint(x, y float64) {
func (dc *DemuxConverter) MoveTo(x, y float64) {
for _, converter := range dc.converters {
converter.AddPoint(x, y)
converter.MoveTo(x, y)
}
}
func (dc *DemuxConverter) LineTo(x, y float64) {
for _, converter := range dc.converters {
converter.LineTo(x, y)
}
}

View file

@ -8,26 +8,23 @@ import (
)
type VertexAdder struct {
command VertexCommand
adder raster.Adder
}
func NewVertexAdder(adder raster.Adder) *VertexAdder {
return &VertexAdder{VertexNoCommand, adder}
return &VertexAdder{adder}
}
func (vertexAdder *VertexAdder) NextCommand(cmd VertexCommand) {
vertexAdder.command = cmd
func (vertexAdder *VertexAdder) NextCommand(cmd LineMarker) {
}
func (vertexAdder *VertexAdder) AddPoint(x, y float64) {
switch vertexAdder.command {
case VertexStartCommand:
func (vertexAdder *VertexAdder) MoveTo(x, y float64) {
vertexAdder.adder.Start(raster.Point{raster.Fix32(x * 256), raster.Fix32(y * 256)})
default:
vertexAdder.adder.Add1(raster.Point{raster.Fix32(x * 256), raster.Fix32(y * 256)})
}
vertexAdder.command = VertexNoCommand
func (vertexAdder *VertexAdder) LineTo(x, y float64) {
vertexAdder.adder.Add1(raster.Point{raster.Fix32(x * 256), raster.Fix32(y * 256)})
}
type PathAdder struct {

View file

@ -9,12 +9,12 @@ import (
)
type PathConverter struct {
converter VertexConverter
converter LineBuilder
ApproximationScale float64
startX, startY, x, y float64
}
func NewPathConverter(converter VertexConverter) *PathConverter {
func NewPathConverter(converter LineBuilder) *PathConverter {
return &PathConverter{converter, 1, 0, 0, 0, 0}
}
@ -26,47 +26,48 @@ func (c *PathConverter) Convert(paths ...*PathStorage) {
case MoveTo:
c.x, c.y = path.vertices[i], path.vertices[i+1]
c.startX, c.startY = c.x, c.y
c.converter.NextCommand(VertexStopCommand)
c.converter.NextCommand(VertexStartCommand)
c.converter.AddPoint(c.x, c.y)
if i != 0 {
c.converter.NextCommand(LineEndMarker)
}
c.converter.MoveTo(c.x, c.y)
i += 2
case LineTo:
c.x, c.y = path.vertices[i], path.vertices[i+1]
if c.startX == c.x && c.startY == c.y {
c.converter.NextCommand(VertexCloseCommand)
c.converter.NextCommand(LineCloseMarker)
}
c.converter.AddPoint(c.x, c.y)
c.converter.NextCommand(VertexJoinCommand)
c.converter.LineTo(c.x, c.y)
c.converter.NextCommand(LineJoinMarker)
i += 2
case QuadCurveTo:
curve.TraceQuad(c.converter, path.vertices[i-2:], 0.5)
c.x, c.y = path.vertices[i+2], path.vertices[i+3]
if c.startX == c.x && c.startY == c.y {
c.converter.NextCommand(VertexCloseCommand)
c.converter.NextCommand(LineCloseMarker)
}
c.converter.AddPoint(c.x, c.y)
c.converter.LineTo(c.x, c.y)
i += 4
case CubicCurveTo:
curve.TraceCubic(c.converter, path.vertices[i-2:], 0.5)
c.x, c.y = path.vertices[i+4], path.vertices[i+5]
if c.startX == c.x && c.startY == c.y {
c.converter.NextCommand(VertexCloseCommand)
c.converter.NextCommand(LineCloseMarker)
}
c.converter.AddPoint(c.x, c.y)
c.converter.LineTo(c.x, c.y)
i += 6
case ArcTo:
c.x, c.y = arc(c.converter, path.vertices[i], path.vertices[i+1], path.vertices[i+2], path.vertices[i+3], path.vertices[i+4], path.vertices[i+5], c.ApproximationScale)
if c.startX == c.x && c.startY == c.y {
c.converter.NextCommand(VertexCloseCommand)
c.converter.NextCommand(LineCloseMarker)
}
c.converter.AddPoint(c.x, c.y)
c.converter.LineTo(c.x, c.y)
i += 6
case Close:
c.converter.NextCommand(VertexCloseCommand)
c.converter.AddPoint(c.startX, c.startY)
c.converter.NextCommand(LineCloseMarker)
c.converter.LineTo(c.startX, c.startY)
}
}
c.converter.NextCommand(VertexStopCommand)
c.converter.NextCommand(LineEndMarker)
}
}
@ -77,9 +78,8 @@ func (c *PathConverter) convertCommand(cmd PathCmd, vertices ...float64) int {
func (c *PathConverter) MoveTo(x, y float64) *PathConverter {
c.x, c.y = x, y
c.startX, c.startY = c.x, c.y
c.converter.NextCommand(VertexStopCommand)
c.converter.NextCommand(VertexStartCommand)
c.converter.AddPoint(c.x, c.y)
c.converter.NextCommand(LineEndMarker)
c.converter.MoveTo(c.x, c.y)
return c
}
@ -91,10 +91,10 @@ func (c *PathConverter) RMoveTo(dx, dy float64) *PathConverter {
func (c *PathConverter) LineTo(x, y float64) *PathConverter {
c.x, c.y = x, y
if c.startX == c.x && c.startY == c.y {
c.converter.NextCommand(VertexCloseCommand)
c.converter.NextCommand(LineCloseMarker)
}
c.converter.AddPoint(c.x, c.y)
c.converter.NextCommand(VertexJoinCommand)
c.converter.LineTo(c.x, c.y)
c.converter.NextCommand(LineJoinMarker)
return c
}
@ -107,9 +107,9 @@ func (c *PathConverter) QuadCurveTo(cx, cy, x, y float64) *PathConverter {
curve.TraceQuad(c.converter, []float64{c.x, c.y, cx, cy, x, y}, 0.5)
c.x, c.y = x, y
if c.startX == c.x && c.startY == c.y {
c.converter.NextCommand(VertexCloseCommand)
c.converter.NextCommand(LineCloseMarker)
}
c.converter.AddPoint(c.x, c.y)
c.converter.LineTo(c.x, c.y)
return c
}
@ -122,9 +122,9 @@ func (c *PathConverter) CubicCurveTo(cx1, cy1, cx2, cy2, x, y float64) *PathConv
curve.TraceCubic(c.converter, []float64{c.x, c.y, cx1, cy1, cx2, cy2, x, y}, 0.5)
c.x, c.y = x, y
if c.startX == c.x && c.startY == c.y {
c.converter.NextCommand(VertexCloseCommand)
c.converter.NextCommand(LineCloseMarker)
}
c.converter.AddPoint(c.x, c.y)
c.converter.LineTo(c.x, c.y)
return c
}
@ -154,9 +154,9 @@ func (c *PathConverter) ArcTo(cx, cy, rx, ry, startAngle, angle float64) *PathCo
c.MoveTo(startX, startY)
c.x, c.y = arc(c.converter, cx, cy, rx, ry, startAngle, angle, c.ApproximationScale)
if c.startX == c.x && c.startY == c.y {
c.converter.NextCommand(VertexCloseCommand)
c.converter.NextCommand(LineCloseMarker)
}
c.converter.AddPoint(c.x, c.y)
c.converter.LineTo(c.x, c.y)
return c
}
@ -166,7 +166,7 @@ func (c *PathConverter) RArcTo(dcx, dcy, rx, ry, startAngle, angle float64) *Pat
}
func (c *PathConverter) Close() *PathConverter {
c.converter.NextCommand(VertexCloseCommand)
c.converter.AddPoint(c.startX, c.startY)
c.converter.NextCommand(LineCloseMarker)
c.converter.LineTo(c.startX, c.startY)
return c
}

View file

@ -60,74 +60,65 @@ func (p *PathStorage) IsEmpty() bool {
return len(p.commands) == 0
}
func (p *PathStorage) Close() *PathStorage {
func (p *PathStorage) Close() {
p.appendToPath(Close)
return p
}
func (p *PathStorage) MoveTo(x, y float64) *PathStorage {
func (p *PathStorage) MoveTo(x, y float64) {
p.appendToPath(MoveTo, x, y)
p.x = x
p.y = y
return p
}
func (p *PathStorage) RMoveTo(dx, dy float64) *PathStorage {
func (p *PathStorage) RMoveTo(dx, dy float64) {
x, y := p.LastPoint()
p.MoveTo(x+dx, y+dy)
return p
}
func (p *PathStorage) LineTo(x, y float64) *PathStorage {
func (p *PathStorage) LineTo(x, y float64) {
if len(p.commands) == 0 { //special case when no move has been done
p.MoveTo(0, 0)
}
p.appendToPath(LineTo, x, y)
p.x = x
p.y = y
return p
}
func (p *PathStorage) RLineTo(dx, dy float64) *PathStorage {
func (p *PathStorage) RLineTo(dx, dy float64) {
x, y := p.LastPoint()
p.LineTo(x+dx, y+dy)
return p
}
func (p *PathStorage) QuadCurveTo(cx, cy, x, y float64) *PathStorage {
func (p *PathStorage) QuadCurveTo(cx, cy, x, y float64) {
if len(p.commands) == 0 { //special case when no move has been done
p.MoveTo(0, 0)
}
p.appendToPath(QuadCurveTo, cx, cy, x, y)
p.x = x
p.y = y
return p
}
func (p *PathStorage) RQuadCurveTo(dcx, dcy, dx, dy float64) *PathStorage {
func (p *PathStorage) RQuadCurveTo(dcx, dcy, dx, dy float64) {
x, y := p.LastPoint()
p.QuadCurveTo(x+dcx, y+dcy, x+dx, y+dy)
return p
}
func (p *PathStorage) CubicCurveTo(cx1, cy1, cx2, cy2, x, y float64) *PathStorage {
func (p *PathStorage) CubicCurveTo(cx1, cy1, cx2, cy2, x, y float64) {
if len(p.commands) == 0 { //special case when no move has been done
p.MoveTo(0, 0)
}
p.appendToPath(CubicCurveTo, cx1, cy1, cx2, cy2, x, y)
p.x = x
p.y = y
return p
}
func (p *PathStorage) RCubicCurveTo(dcx1, dcy1, dcx2, dcy2, dx, dy float64) *PathStorage {
func (p *PathStorage) RCubicCurveTo(dcx1, dcy1, dcx2, dcy2, dx, dy float64) {
x, y := p.LastPoint()
p.CubicCurveTo(x+dcx1, y+dcy1, x+dcx2, y+dcy2, x+dx, y+dy)
return p
}
func (p *PathStorage) ArcTo(cx, cy, rx, ry, startAngle, angle float64) *PathStorage {
func (p *PathStorage) ArcTo(cx, cy, rx, ry, startAngle, angle float64) {
endAngle := startAngle + angle
clockWise := true
if angle < 0 {
@ -153,13 +144,11 @@ func (p *PathStorage) ArcTo(cx, cy, rx, ry, startAngle, angle float64) *PathStor
p.appendToPath(ArcTo, cx, cy, rx, ry, startAngle, angle)
p.x = cx + math.Cos(endAngle)*rx
p.y = cy + math.Sin(endAngle)*ry
return p
}
func (p *PathStorage) RArcTo(dcx, dcy, rx, ry, startAngle, angle float64) *PathStorage {
func (p *PathStorage) RArcTo(dcx, dcy, rx, ry, startAngle, angle float64) {
x, y := p.LastPoint()
p.ArcTo(x+dcx, y+dcy, rx, ry, startAngle, angle)
return p
}
func (p *PathStorage) String() string {

View file

@ -20,17 +20,17 @@ const (
)
type LineStroker struct {
Next VertexConverter
Next LineBuilder
HalfLineWidth float64
Cap Cap
Join Join
vertices []float64
rewind []float64
x, y, nx, ny float64
command VertexCommand
command LineMarker
}
func NewLineStroker(c Cap, j Join, converter VertexConverter) *LineStroker {
func NewLineStroker(c Cap, j Join, converter LineBuilder) *LineStroker {
l := new(LineStroker)
l.Next = converter
l.HalfLineWidth = 0.5
@ -38,27 +38,29 @@ func NewLineStroker(c Cap, j Join, converter VertexConverter) *LineStroker {
l.rewind = make([]float64, 0, 256)
l.Cap = c
l.Join = j
l.command = VertexNoCommand
l.command = LineNoneMarker
return l
}
func (l *LineStroker) NextCommand(command VertexCommand) {
func (l *LineStroker) NextCommand(command LineMarker) {
l.command = command
if command == VertexStopCommand {
l.Next.NextCommand(VertexStartCommand)
for i, j := 0, 1; j < len(l.vertices); i, j = i+2, j+2 {
l.Next.AddPoint(l.vertices[i], l.vertices[j])
l.Next.NextCommand(VertexNoCommand)
if command == LineEndMarker {
if len(l.vertices) > 1 {
l.Next.MoveTo(l.vertices[0], l.vertices[1])
for i, j := 2, 3; j < len(l.vertices); i, j = i+2, j+2 {
l.Next.LineTo(l.vertices[i], l.vertices[j])
l.Next.NextCommand(LineNoneMarker)
}
}
for i, j := len(l.rewind)-2, len(l.rewind)-1; j > 0; i, j = i-2, j-2 {
l.Next.NextCommand(VertexNoCommand)
l.Next.AddPoint(l.rewind[i], l.rewind[j])
l.Next.NextCommand(LineNoneMarker)
l.Next.LineTo(l.rewind[i], l.rewind[j])
}
if len(l.vertices) > 1 {
l.Next.NextCommand(VertexNoCommand)
l.Next.AddPoint(l.vertices[0], l.vertices[1])
l.Next.NextCommand(LineNoneMarker)
l.Next.LineTo(l.vertices[0], l.vertices[1])
}
l.Next.NextCommand(VertexStopCommand)
l.Next.NextCommand(LineEndMarker)
// reinit vertices
l.vertices = l.vertices[0:0]
l.rewind = l.rewind[0:0]
@ -66,20 +68,22 @@ func (l *LineStroker) NextCommand(command VertexCommand) {
}
}
func (l *LineStroker) AddPoint(x, y float64) {
switch l.command {
case VertexNoCommand:
l.line(l.x, l.y, x, y)
case VertexJoinCommand:
l.joinLine(l.x, l.y, l.nx, l.ny, x, y)
case VertexStartCommand:
func (l *LineStroker) MoveTo(x, y float64) {
l.x, l.y = x, y
case VertexCloseCommand:
}
func (l *LineStroker) LineTo(x, y float64) {
switch l.command {
case LineJoinMarker:
l.joinLine(l.x, l.y, l.nx, l.ny, x, y)
case LineCloseMarker:
l.line(l.x, l.y, x, y)
l.joinLine(l.x, l.y, l.nx, l.ny, x, y)
l.closePolygon()
default:
l.line(l.x, l.y, x, y)
}
l.command = VertexNoCommand
l.command = LineNoneMarker
}
func (l *LineStroker) appendVertex(vertices ...float64) {

View file

@ -254,22 +254,28 @@ func fequals(float1, float2 float64) bool {
// this VertexConverter apply the Matrix transformation tr
type VertexMatrixTransform struct {
tr MatrixTransform
Next VertexConverter
Next LineBuilder
}
func NewVertexMatrixTransform(tr MatrixTransform, converter VertexConverter) *VertexMatrixTransform {
func NewVertexMatrixTransform(tr MatrixTransform, converter LineBuilder) *VertexMatrixTransform {
return &VertexMatrixTransform{tr, converter}
}
// Vertex Matrix Transform
func (vmt *VertexMatrixTransform) NextCommand(command VertexCommand) {
func (vmt *VertexMatrixTransform) NextCommand(command LineMarker) {
vmt.Next.NextCommand(command)
}
func (vmt *VertexMatrixTransform) AddPoint(x, y float64) {
func (vmt *VertexMatrixTransform) MoveTo(x, y float64) {
u := x*vmt.tr[0] + y*vmt.tr[2] + vmt.tr[4]
v := x*vmt.tr[1] + y*vmt.tr[3] + vmt.tr[5]
vmt.Next.AddPoint(u, v)
vmt.Next.MoveTo(u, v)
}
func (vmt *VertexMatrixTransform) LineTo(x, y float64) {
u := x*vmt.tr[0] + y*vmt.tr[2] + vmt.tr[4]
v := x*vmt.tr[1] + y*vmt.tr[3] + vmt.tr[5]
vmt.Next.LineTo(u, v)
}
// this adder apply a Matrix transformation to points

View file

@ -3,17 +3,21 @@
package draw2d
type VertexCommand byte
type LineMarker byte
const (
VertexNoCommand VertexCommand = iota
VertexStartCommand
VertexJoinCommand
VertexCloseCommand
VertexStopCommand
LineNoneMarker LineMarker = iota
// Mark the current point of the line as a join to it can draw some specific join Bevel, Miter, Rount
LineJoinMarker
// Mark the current point of the line as closed so it draw a line from the current
// position to the point specified by the last start marker.
LineCloseMarker
// Mark the current point of the line as finished. This ending maker allow caps to be drawn
LineEndMarker
)
type VertexConverter interface {
NextCommand(cmd VertexCommand)
AddPoint(x, y float64)
type LineBuilder interface {
NextCommand(cmd LineMarker)
MoveTo(x, y float64)
LineTo(x, y float64)
}