merge modifs

This commit is contained in:
Laurent Le Goff 2011-05-18 09:51:42 +02:00
commit 52748a2494
4 changed files with 121 additions and 3 deletions

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syntax:glob
.DS_Store
.git
.gitignore
*.[568ao]
_obj
*.ao
*.so
*.pyc
._*
.nfs.*
[568a].out
*~
*.orig
core
_obj
_test
out.png
_testmain.go
syntax: regexp
\.dll$
^.*/core.[0-9]*$

7
draw2d/curve/Makefile Normal file
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include $(GOROOT)/src/Make.inc
TARG=draw2d.googlecode.com/hg/draw2d/curve
GOFILES=\
curve_float64.go\
include $(GOROOT)/src/Make.pkg

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// Copyright 2010 The draw2d Authors. All rights reserved.
// created: 17/05/2011 by Laurent Le Goff
package curve
import (
"math"
)
var (
m_distance_tolerance float64 = 0.25
)
type CubicCurveFloat64 struct {
x1, y1, x2, y2, x3, y3, x4, y4 float64
segments []float64
}
func NewCubicCurveFloat64(x1, y1, x2, y2, x3, y3, x4, y4 float64) (*CubicCurveFloat64){
return &CubicCurveFloat64{x1, y1, x2, y2, x3, y3, x4, y4, make([]float64, 0, 2)}
}
func (c *CubicCurveFloat64) addPoint(x, y float64) {
c.segments = append(c.segments, x, y)
}
func (c *CubicCurveFloat64) Subdivide() (c1, c2 *CubicCurveFloat64) {
// Calculate all the mid-points of the line segments
//----------------------
x12 := (c.x1 + c.x2) / 2
y12 := (c.y1 + c.y2) / 2
x23 := (c.x2 + c.x3) / 2
y23 := (c.y2 + c.y3) / 2
x34 := (c.x3 + c.x4) / 2
y34 := (c.y3 + c.y4) / 2
x123 := (x12 + x23) / 2
y123 := (y12 + y23) / 2
x234 := (x23 + x34) / 2
y234 := (y23 + y34) / 2
x1234 := (x123 + x234) / 2
y1234 := (y123 + y234) / 2
c1 = &CubicCurveFloat64{c.x1, c.y1, x12, y12, x123, y123, x1234, y1234, c.segments}
c2 = &CubicCurveFloat64{x1234, y1234, x234, y234, x34, y34, c.x4, c.y4, c.segments}
return
}
// subdivide the curve in straight lines using Casteljau subdivision
// and computing minimal distance tolerance
func (c *CubicCurveFloat64) SegmentCasteljau() []float64{
// reinit segments
c.segments = make([]float64, 0, 2)
c.addPoint(c.x1, c.y1)
c.segmentCasteljauRec()
c.addPoint(c.x4, c.y4)
return c.segments
}
func (c *CubicCurveFloat64) segmentCasteljauRec() {
c1, c2 := c.Subdivide()
// Try to approximate the full cubic curve by a single straight line
//------------------
dx := c.x4 - c.x1
dy := c.y4 - c.y1
d2 := math.Fabs(((c.x2-c.x4)*dy - (c.y2-c.y4)*dx))
d3 := math.Fabs(((c.x3-c.x4)*dy - (c.y3-c.y4)*dx))
if (d2+d3)*(d2+d3) < m_distance_tolerance*(dx*dx+dy*dy) {
c.addPoint(c2.x1, c2.y1)
return
} else {
// Continue subdivision
//----------------------
c1.segmentCasteljauRec()
c2.segments = c1.segments
c2.segmentCasteljauRec()
c.segments = c2.segments
}
}

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package curve
import (
"testing"
"log"
)
var (
cf64Test1 = NewCubicCurveFloat64(100, 100, 200, 100, 100, 200, 200, 200)
)
func BenchmarkCubicCurveCasteljauTest1(b *testing.B) {
var s []float64
for i := 0; i < b.N; i++ {
s = cf64Test1.SegmentCasteljau()
}
log.Printf("Num of points: %d\n", len(s));
}