1 files changed, 67 insertions, 0 deletions
diff --git a/Godeps/_workspace/src/code.google.com/p/draw2d/draw2d/curve/cubic_float64.go b/Godeps/_workspace/src/code.google.com/p/draw2d/draw2d/curve/cubic_float64.go
new file mode 100644
index 000000000..64a7ac639
--- /dev/null
+++ b/Godeps/_workspace/src/code.google.com/p/draw2d/draw2d/curve/cubic_float64.go
@@ -0,0 +1,67 @@
+// Copyright 2010 The draw2d Authors. All rights reserved.
+// created: 17/05/2011 by Laurent Le Goff
+package curve
+
+import (
+	"math"
+)
+
+const (
+	CurveRecursionLimit = 32
+)
+
+//	X1, Y1, X2, Y2, X3, Y3, X4, Y4 float64
+type CubicCurveFloat64 [8]float64
+
+type LineTracer interface {
+	LineTo(x, y float64)
+}
+
+func (c *CubicCurveFloat64) Subdivide(c1, c2 *CubicCurveFloat64) (x23, y23 float64) {
+	// Calculate all the mid-points of the line segments
+	//----------------------
+	c1[0], c1[1] = c[0], c[1]
+	c2[6], c2[7] = c[6], c[7]
+	c1[2] = (c[0] + c[2]) / 2
+	c1[3] = (c[1] + c[3]) / 2
+	x23 = (c[2] + c[4]) / 2
+	y23 = (c[3] + c[5]) / 2
+	c2[4] = (c[4] + c[6]) / 2
+	c2[5] = (c[5] + c[7]) / 2
+	c1[4] = (c1[2] + x23) / 2
+	c1[5] = (c1[3] + y23) / 2
+	c2[2] = (x23 + c2[4]) / 2
+	c2[3] = (y23 + c2[5]) / 2
+	c1[6] = (c1[4] + c2[2]) / 2
+	c1[7] = (c1[5] + c2[3]) / 2
+	c2[0], c2[1] = c1[6], c1[7]
+	return
+}
+
+func (curve *CubicCurveFloat64) Segment(t LineTracer, flattening_threshold float64) {
+	var curves [CurveRecursionLimit]CubicCurveFloat64
+	curves[0] = *curve
+	i := 0
+	// current curve
+	var c *CubicCurveFloat64
+
+	var dx, dy, d2, d3 float64
+
+	for i >= 0 {
+		c = &curves[i]
+		dx = c[6] - c[0]
+		dy = c[7] - c[1]
+
+		d2 = math.Abs(((c[2]-c[6])*dy - (c[3]-c[7])*dx))
+		d3 = math.Abs(((c[4]-c[6])*dy - (c[5]-c[7])*dx))
+
+		if (d2+d3)*(d2+d3) < flattening_threshold*(dx*dx+dy*dy) || i == len(curves)-1 {
+			t.LineTo(c[6], c[7])
+			i--
+		} else {
+			// second half of bezier go lower onto the stack
+			c.Subdivide(&curves[i+1], &curves[i])
+			i++
+		}
+	}
+}