1 files changed, 280 insertions, 0 deletions
diff --git a/Godeps/_workspace/src/code.google.com/p/freetype-go/freetype/raster/geom.go b/Godeps/_workspace/src/code.google.com/p/freetype-go/freetype/raster/geom.go
new file mode 100644
index 000000000..63c86e6ab
--- /dev/null
+++ b/Godeps/_workspace/src/code.google.com/p/freetype-go/freetype/raster/geom.go
@@ -0,0 +1,280 @@
+// Copyright 2010 The Freetype-Go Authors. All rights reserved.
+// Use of this source code is governed by your choice of either the
+// FreeType License or the GNU General Public License version 2 (or
+// any later version), both of which can be found in the LICENSE file.
+
+package raster
+
+import (
+	"fmt"
+	"math"
+)
+
+// A Fix32 is a 24.8 fixed point number.
+type Fix32 int32
+
+// A Fix64 is a 48.16 fixed point number.
+type Fix64 int64
+
+// String returns a human-readable representation of a 24.8 fixed point number.
+// For example, the number one-and-a-quarter becomes "1:064".
+func (x Fix32) String() string {
+	if x < 0 {
+		x = -x
+		return fmt.Sprintf("-%d:%03d", int32(x/256), int32(x%256))
+	}
+	return fmt.Sprintf("%d:%03d", int32(x/256), int32(x%256))
+}
+
+// String returns a human-readable representation of a 48.16 fixed point number.
+// For example, the number one-and-a-quarter becomes "1:16384".
+func (x Fix64) String() string {
+	if x < 0 {
+		x = -x
+		return fmt.Sprintf("-%d:%05d", int64(x/65536), int64(x%65536))
+	}
+	return fmt.Sprintf("%d:%05d", int64(x/65536), int64(x%65536))
+}
+
+// maxAbs returns the maximum of abs(a) and abs(b).
+func maxAbs(a, b Fix32) Fix32 {
+	if a < 0 {
+		a = -a
+	}
+	if b < 0 {
+		b = -b
+	}
+	if a < b {
+		return b
+	}
+	return a
+}
+
+// A Point represents a two-dimensional point or vector, in 24.8 fixed point
+// format.
+type Point struct {
+	X, Y Fix32
+}
+
+// String returns a human-readable representation of a Point.
+func (p Point) String() string {
+	return "(" + p.X.String() + ", " + p.Y.String() + ")"
+}
+
+// Add returns the vector p + q.
+func (p Point) Add(q Point) Point {
+	return Point{p.X + q.X, p.Y + q.Y}
+}
+
+// Sub returns the vector p - q.
+func (p Point) Sub(q Point) Point {
+	return Point{p.X - q.X, p.Y - q.Y}
+}
+
+// Mul returns the vector k * p.
+func (p Point) Mul(k Fix32) Point {
+	return Point{p.X * k / 256, p.Y * k / 256}
+}
+
+// Neg returns the vector -p, or equivalently p rotated by 180 degrees.
+func (p Point) Neg() Point {
+	return Point{-p.X, -p.Y}
+}
+
+// Dot returns the dot product p·q.
+func (p Point) Dot(q Point) Fix64 {
+	px, py := int64(p.X), int64(p.Y)
+	qx, qy := int64(q.X), int64(q.Y)
+	return Fix64(px*qx + py*qy)
+}
+
+// Len returns the length of the vector p.
+func (p Point) Len() Fix32 {
+	// TODO(nigeltao): use fixed point math.
+	x := float64(p.X)
+	y := float64(p.Y)
+	return Fix32(math.Sqrt(x*x + y*y))
+}
+
+// Norm returns the vector p normalized to the given length, or the zero Point
+// if p is degenerate.
+func (p Point) Norm(length Fix32) Point {
+	d := p.Len()
+	if d == 0 {
+		return Point{}
+	}
+	s, t := int64(length), int64(d)
+	x := int64(p.X) * s / t
+	y := int64(p.Y) * s / t
+	return Point{Fix32(x), Fix32(y)}
+}
+
+// Rot45CW returns the vector p rotated clockwise by 45 degrees.
+// Note that the Y-axis grows downwards, so {1, 0}.Rot45CW is {1/√2, 1/√2}.
+func (p Point) Rot45CW() Point {
+	// 181/256 is approximately 1/√2, or sin(π/4).
+	px, py := int64(p.X), int64(p.Y)
+	qx := (+px - py) * 181 / 256
+	qy := (+px + py) * 181 / 256
+	return Point{Fix32(qx), Fix32(qy)}
+}
+
+// Rot90CW returns the vector p rotated clockwise by 90 degrees.
+// Note that the Y-axis grows downwards, so {1, 0}.Rot90CW is {0, 1}.
+func (p Point) Rot90CW() Point {
+	return Point{-p.Y, p.X}
+}
+
+// Rot135CW returns the vector p rotated clockwise by 135 degrees.
+// Note that the Y-axis grows downwards, so {1, 0}.Rot135CW is {-1/√2, 1/√2}.
+func (p Point) Rot135CW() Point {
+	// 181/256 is approximately 1/√2, or sin(π/4).
+	px, py := int64(p.X), int64(p.Y)
+	qx := (-px - py) * 181 / 256
+	qy := (+px - py) * 181 / 256
+	return Point{Fix32(qx), Fix32(qy)}
+}
+
+// Rot45CCW returns the vector p rotated counter-clockwise by 45 degrees.
+// Note that the Y-axis grows downwards, so {1, 0}.Rot45CCW is {1/√2, -1/√2}.
+func (p Point) Rot45CCW() Point {
+	// 181/256 is approximately 1/√2, or sin(π/4).
+	px, py := int64(p.X), int64(p.Y)
+	qx := (+px + py) * 181 / 256
+	qy := (-px + py) * 181 / 256
+	return Point{Fix32(qx), Fix32(qy)}
+}
+
+// Rot90CCW returns the vector p rotated counter-clockwise by 90 degrees.
+// Note that the Y-axis grows downwards, so {1, 0}.Rot90CCW is {0, -1}.
+func (p Point) Rot90CCW() Point {
+	return Point{p.Y, -p.X}
+}
+
+// Rot135CCW returns the vector p rotated counter-clockwise by 135 degrees.
+// Note that the Y-axis grows downwards, so {1, 0}.Rot135CCW is {-1/√2, -1/√2}.
+func (p Point) Rot135CCW() Point {
+	// 181/256 is approximately 1/√2, or sin(π/4).
+	px, py := int64(p.X), int64(p.Y)
+	qx := (-px + py) * 181 / 256
+	qy := (-px - py) * 181 / 256
+	return Point{Fix32(qx), Fix32(qy)}
+}
+
+// An Adder accumulates points on a curve.
+type Adder interface {
+	// Start starts a new curve at the given point.
+	Start(a Point)
+	// Add1 adds a linear segment to the current curve.
+	Add1(b Point)
+	// Add2 adds a quadratic segment to the current curve.
+	Add2(b, c Point)
+	// Add3 adds a cubic segment to the current curve.
+	Add3(b, c, d Point)
+}
+
+// A Path is a sequence of curves, and a curve is a start point followed by a
+// sequence of linear, quadratic or cubic segments.
+type Path []Fix32
+
+// String returns a human-readable representation of a Path.
+func (p Path) String() string {
+	s := ""
+	for i := 0; i < len(p); {
+		if i != 0 {
+			s += " "
+		}
+		switch p[i] {
+		case 0:
+			s += "S0" + fmt.Sprint([]Fix32(p[i+1:i+3]))
+			i += 4
+		case 1:
+			s += "A1" + fmt.Sprint([]Fix32(p[i+1:i+3]))
+			i += 4
+		case 2:
+			s += "A2" + fmt.Sprint([]Fix32(p[i+1:i+5]))
+			i += 6
+		case 3:
+			s += "A3" + fmt.Sprint([]Fix32(p[i+1:i+7]))
+			i += 8
+		default:
+			panic("freetype/raster: bad path")
+		}
+	}
+	return s
+}
+
+// Clear cancels any previous calls to p.Start or p.AddXxx.
+func (p *Path) Clear() {
+	*p = (*p)[:0]
+}
+
+// Start starts a new curve at the given point.
+func (p *Path) Start(a Point) {
+	*p = append(*p, 0, a.X, a.Y, 0)
+}
+
+// Add1 adds a linear segment to the current curve.
+func (p *Path) Add1(b Point) {
+	*p = append(*p, 1, b.X, b.Y, 1)
+}
+
+// Add2 adds a quadratic segment to the current curve.
+func (p *Path) Add2(b, c Point) {
+	*p = append(*p, 2, b.X, b.Y, c.X, c.Y, 2)
+}
+
+// Add3 adds a cubic segment to the current curve.
+func (p *Path) Add3(b, c, d Point) {
+	*p = append(*p, 3, b.X, b.Y, c.X, c.Y, d.X, d.Y, 3)
+}
+
+// AddPath adds the Path q to p.
+func (p *Path) AddPath(q Path) {
+	*p = append(*p, q...)
+}
+
+// AddStroke adds a stroked Path.
+func (p *Path) AddStroke(q Path, width Fix32, cr Capper, jr Joiner) {
+	Stroke(p, q, width, cr, jr)
+}
+
+// firstPoint returns the first point in a non-empty Path.
+func (p Path) firstPoint() Point {
+	return Point{p[1], p[2]}
+}
+
+// lastPoint returns the last point in a non-empty Path.
+func (p Path) lastPoint() Point {
+	return Point{p[len(p)-3], p[len(p)-2]}
+}
+
+// addPathReversed adds q reversed to p.
+// For example, if q consists of a linear segment from A to B followed by a
+// quadratic segment from B to C to D, then the values of q looks like:
+// index: 01234567890123
+// value: 0AA01BB12CCDD2
+// So, when adding q backwards to p, we want to Add2(C, B) followed by Add1(A).
+func addPathReversed(p Adder, q Path) {
+	if len(q) == 0 {
+		return
+	}
+	i := len(q) - 1
+	for {
+		switch q[i] {
+		case 0:
+			return
+		case 1:
+			i -= 4
+			p.Add1(Point{q[i-2], q[i-1]})
+		case 2:
+			i -= 6
+			p.Add2(Point{q[i+2], q[i+3]}, Point{q[i-2], q[i-1]})
+		case 3:
+			i -= 8
+			p.Add3(Point{q[i+4], q[i+5]}, Point{q[i+2], q[i+3]}, Point{q[i-2], q[i-1]})
+		default:
+			panic("freetype/raster: bad path")
+		}
+	}
+}