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Diffstat (limited to 'Godeps/_workspace/src/code.google.com/p/freetype-go/freetype/raster/geom.go')
-rw-r--r-- | Godeps/_workspace/src/code.google.com/p/freetype-go/freetype/raster/geom.go | 280 |
1 files changed, 0 insertions, 280 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 deleted file mode 100644 index 63c86e6ab..000000000 --- a/Godeps/_workspace/src/code.google.com/p/freetype-go/freetype/raster/geom.go +++ /dev/null @@ -1,280 +0,0 @@ -// 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") - } - } -} |