Freetype-Go: Initial code check-in.
R=r, rsc CC=golang-dev http://codereview.appspot.com/841042
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14
AUTHORS
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14
AUTHORS
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# This is the official list of Freetype-Go authors for copyright purposes.
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# This file is distinct from the CONTRIBUTORS files.
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# See the latter for an explanation.
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#
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# Freetype-Go is derived from Freetype, which is written in C. The latter
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# is copyright 1996-2010 David Turner, Robert Wilhelm, and Werner Lemberg.
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# Names should be added to this file as
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# Name or Organization <email address>
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# The email address is not required for organizations.
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# Please keep the list sorted.
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Google Inc.
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31
CONTRIBUTORS
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31
CONTRIBUTORS
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# This is the official list of people who can contribute
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# (and typically have contributed) code to the Freetype-Go repository.
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# The AUTHORS file lists the copyright holders; this file
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# lists people. For example, Google employees are listed here
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# but not in AUTHORS, because Google holds the copyright.
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#
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# The submission process automatically checks to make sure
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# that people submitting code are listed in this file (by email address).
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#
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# Names should be added to this file only after verifying that
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# the individual or the individual's organization has agreed to
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# the appropriate Contributor License Agreement, found here:
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#
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# http://code.google.com/legal/individual-cla-v1.0.html
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# http://code.google.com/legal/corporate-cla-v1.0.html
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#
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# The agreement for individuals can be filled out on the web.
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#
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# When adding J Random Contributor's name to this file,
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# either J's name or J's organization's name should be
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# added to the AUTHORS file, depending on whether the
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# individual or corporate CLA was used.
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# Names should be added to this file like so:
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# Name <email address>
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# Please keep the list sorted.
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Nigel Tao <nigeltao@golang.org>
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Rob Pike <r@golang.org>
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Russ Cox <rsc@golang.org>
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10
LICENSE
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10
LICENSE
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Use of the Freetype-Go software is subject to your choice of exactly one of
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the following two licenses:
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* The FreeType License, which is similar to the original BSD license with
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an advertising clause, or
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* The GNU General Public License (GPL), version 2 or later.
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The text of these licenses are available in the licenses/ftl.txt and the
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licenses/gpl.txt files respectively. They are also available at
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http://freetype.sourceforge.net/license.html
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19
README
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19
README
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This is a port of the Freetype font rasterizer (www.freetype.org) to the Go
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programming language (golang.org).
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It is an incomplete port:
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* It only supports TrueType fonts, and not Type 1 fonts nor bitmap fonts.
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* It only supports the Unicode encoding.
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There are also some implementation differences:
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* It uses a 24.8 fixed point co-ordinate system everywhere internally,
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as opposed to the original Freetype's mix of 26.6 (or 10.6 for 16-bit
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systems) in some places, and 24.8 in the "smooth" rasterizer.
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Freetype-Go is derived from Freetype, which is written in C. Freetype is
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copyright 1996-2010 David Turner, Robert Wilhelm, and Werner Lemberg.
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Freetype-Go is copyright The Freetype-Go Authors, who are listed in the
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AUTHORS file.
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The Freetype-Go homepage is http://code.google.com/p/freetype-go/
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173
example/raster/main.go
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173
example/raster/main.go
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// Copyright 2010 The Freetype-Go Authors. All rights reserved.
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// Use of this source code is governed by your choice of either the
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// FreeType License or the GNU General Public License version 2,
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// both of which can be found in the LICENSE file.
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package main
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import (
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"bufio"
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"exp/draw"
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"fmt"
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"image"
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"image/png"
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"log"
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"os"
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"freetype-go.googlecode.com/hg/freetype/raster"
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)
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type node struct {
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x, y, degree int
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}
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// These contours "outside" and "inside" are from the `A' glyph from the Droid
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// Serif Regular font.
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var outside = []node{
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node{414, 489, 1},
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node{336, 274, 2},
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node{327, 250, 0},
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node{322, 226, 2},
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node{317, 203, 0},
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node{317, 186, 2},
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node{317, 134, 0},
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node{350, 110, 2},
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node{384, 86, 0},
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node{453, 86, 1},
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node{500, 86, 1},
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node{500, 0, 1},
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node{0, 0, 1},
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node{0, 86, 1},
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node{39, 86, 2},
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node{69, 86, 0},
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node{90, 92, 2},
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node{111, 99, 0},
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node{128, 117, 2},
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node{145, 135, 0},
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node{160, 166, 2},
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node{176, 197, 0},
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node{195, 246, 1},
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node{649, 1462, 1},
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node{809, 1462, 1},
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node{1272, 195, 2},
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node{1284, 163, 0},
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node{1296, 142, 2},
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node{1309, 121, 0},
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node{1326, 108, 2},
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node{1343, 96, 0},
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node{1365, 91, 2},
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node{1387, 86, 0},
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node{1417, 86, 1},
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node{1444, 86, 1},
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node{1444, 0, 1},
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node{881, 0, 1},
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node{881, 86, 1},
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node{928, 86, 2},
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node{1051, 86, 0},
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node{1051, 184, 2},
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node{1051, 201, 0},
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node{1046, 219, 2},
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node{1042, 237, 0},
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node{1034, 260, 1},
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node{952, 489, 1},
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node{414, 489, -1},
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}
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var inside = []node{
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node{686, 1274, 1},
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node{453, 592, 1},
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node{915, 592, 1},
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node{686, 1274, -1},
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}
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func p(n node) raster.Point {
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x, y := 20+n.x/4, 380-n.y/4
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return raster.Point{raster.Fixed(x * 256), raster.Fixed(y * 256)}
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}
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func contour(r *raster.Rasterizer, ns []node) {
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if len(ns) == 0 {
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return
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}
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i := 0
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r.Start(p(ns[i]))
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for {
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switch ns[i].degree {
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case -1:
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// -1 signifies end-of-contour.
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return
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case 1:
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i += 1
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r.Move1(p(ns[i]))
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case 2:
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i += 2
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r.Move2(p(ns[i-1]), p(ns[i]))
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default:
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panic("bad degree")
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}
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}
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}
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func showNodes(m *image.RGBA, ns []node) {
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for _, n := range ns {
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p := p(n)
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x, y := int(p.X)/256, int(p.Y)/256
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if x < 0 || x >= m.Width() || y < 0 || y >= m.Height() {
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continue
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}
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var c image.Color
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switch n.degree {
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case 0:
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c = image.Aqua
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case 1:
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c = image.Red
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case 2:
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c = image.Red
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}
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if c != nil {
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m.Set(x, y, c)
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}
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}
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}
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func main() {
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// Rasterize the contours to a mask image.
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const (
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w = 400
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h = 400
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)
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r := raster.New(w, h)
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contour(r, outside)
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contour(r, inside)
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mask := image.NewAlpha(w, h)
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r.Rasterize(raster.AlphaSrcPainter(mask))
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// Draw the mask image (in gray) onto an RGBA image.
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rgba := image.NewRGBA(w, h)
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gray := image.ColorImage{image.AlphaColor{0x1f}}
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draw.Draw(rgba, draw.Rect(0, 0, w, h), image.Black, draw.ZP)
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draw.DrawMask(rgba, draw.Rect(0, 0, w, h), gray, draw.ZP, mask, draw.ZP, draw.Over)
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showNodes(rgba, outside)
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showNodes(rgba, inside)
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// Save that RGBA image to disk.
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f, err := os.Open("out.png", os.O_CREAT|os.O_WRONLY, 0600)
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if err != nil {
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log.Stderr(err)
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return
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}
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defer f.Close()
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b := bufio.NewWriter(f)
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err = png.Encode(b, rgba)
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if err != nil {
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log.Stderr(err)
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return
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}
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err = b.Flush()
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if err != nil {
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log.Stderr(err)
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return
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}
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fmt.Println("Wrote out.png OK.")
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}
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13
freetype/raster/Makefile
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13
freetype/raster/Makefile
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# Copyright 2010 The Freetype-Go Authors. All rights reserved.
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# Use of this source code is governed by your choice of either the
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# FreeType License or the GNU General Public License version 2,
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# both of which can be found in the LICENSE file.
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include $(GOROOT)/src/Make.$(GOARCH)
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TARG=freetype-go.googlecode.com/hg/freetype/raster
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GOFILES=\
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raster.go\
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include $(GOROOT)/src/Make.pkg
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517
freetype/raster/raster.go
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517
freetype/raster/raster.go
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// Copyright 2010 The Freetype-Go Authors. All rights reserved.
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// Use of this source code is governed by your choice of either the
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// FreeType License or the GNU General Public License version 2,
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// both of which can be found in the LICENSE file.
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// The raster package provides an anti-aliasing 2-D rasterizer.
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//
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// It is part of the larger Freetype-Go suite of font-related packages,
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// but the raster package is not specific to font rasterization, and can
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// be used standalone without any other Freetype-Go package.
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//
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// Rasterization is done by the same area/coverage accumulation algorithm
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// as the Freetype "smooth" module, and the Anti-Grain Geometry library.
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// A description of the area/coverage algorithm is at
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// http://projects.tuxee.net/cl-vectors/section-the-cl-aa-algorithm
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package raster
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import (
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"fmt"
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"image"
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"strconv"
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)
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// A Painter knows how to paint a span, and a span is a horizontal segment
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// of a certain alpha. A fully opaque span has alpha == 1<<32-1. A span's
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// alpha is non-zero until the final Paint call of the rasterization, which
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// has all arguments zero.
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// TODO(nigeltao): Is it worth batching spans, so that Paint takes a []Span
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// instead of a single Span?
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type Painter interface {
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Paint(yi, xi0, xi1 int, alpha uint32)
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}
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// The PainterFunc type adapts an ordinary function to the Painter interface.
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type PainterFunc func(yi, xi0, xi1 int, alpha uint32)
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// Paint just delegates the call to f.
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func (f PainterFunc) Paint(yi, xi0, xi1 int, alpha uint32) {
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f(yi, xi0, xi1, alpha)
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}
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// A 24.8 fixed point number.
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type Fixed int32
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// Human-readable format for a 24.8 fixed point number. For example, the
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// number one-and-a-quarter becomes "1:064".
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func (x Fixed) String() string {
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i, f := x/256, x%256
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if f < 0 {
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f = -f
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}
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return fmt.Sprintf("%d:%03d", i, f)
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}
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// Two-dimensional point, in 24.8 fixed point format.
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type Point struct {
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X, Y Fixed
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}
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// A cell is part of a linked list (for a given yi coordinate) of accumulated
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// area/coverage for the pixel at (xi, yi).
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type cell struct {
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xi int
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area, cover int
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next int
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}
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type Rasterizer struct {
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// If false, the default behavior is to use the even-odd winding fill
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// rule during Rasterize.
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UseNonZeroWinding bool
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// The width of the Rasterizer. The height is implicit in len(cellIndex).
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width int
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// quadSplitScale is the scaling factor used to determine how many times
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// to decompose a quadratic segment into a linear approximation.
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quadSplitScale int
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// The current pen position.
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a Point
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// The current cell and its area/coverage being accumulated.
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xi, yi int
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area, cover int
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// Saved cells.
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cell []cell
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// Linked list of cells, one per row.
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cellIndex []int
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// Buffers.
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cellBuf [256]cell
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cellIndexBuf [64]int
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}
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// findCell returns the index in r.cell for the cell corresponding to
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// (r.xi, r.yi). The cell is created if necessary.
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func (r *Rasterizer) findCell() int {
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if r.yi < 0 || r.yi >= len(r.cellIndex) {
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return -1
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}
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xi := r.xi
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if xi < 0 {
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xi = -1
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} else if xi > r.width {
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xi = r.width
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}
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i, prev := r.cellIndex[r.yi], -1
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for i != -1 && r.cell[i].xi <= xi {
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if r.cell[i].xi == xi {
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return i
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}
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i, prev = r.cell[i].next, i
|
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}
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c := len(r.cell)
|
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if c == cap(r.cell) {
|
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buf := make([]cell, c, 4*c)
|
||||
copy(buf, r.cell)
|
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r.cell = buf[0 : c+1]
|
||||
} else {
|
||||
r.cell = r.cell[0 : c+1]
|
||||
}
|
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r.cell[c] = cell{xi, 0, 0, i}
|
||||
if prev == -1 {
|
||||
r.cellIndex[r.yi] = c
|
||||
} else {
|
||||
r.cell[prev].next = c
|
||||
}
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||||
return c
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||||
}
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|
||||
// saveCell saves any accumulated r.area/r.cover for (r.xi, r.yi).
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func (r *Rasterizer) saveCell() {
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||||
if r.area != 0 || r.cover != 0 {
|
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i := r.findCell()
|
||||
if i != -1 {
|
||||
r.cell[i].area += r.area
|
||||
r.cell[i].cover += r.cover
|
||||
}
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||||
r.area = 0
|
||||
r.cover = 0
|
||||
}
|
||||
}
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// setCell sets the (xi, yi) cell that r is accumulating area/coverage for.
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func (r *Rasterizer) setCell(xi, yi int) {
|
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if r.xi != xi || r.yi != yi {
|
||||
r.saveCell()
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||||
r.xi, r.yi = xi, yi
|
||||
}
|
||||
}
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||||
|
||||
// scan accumulates area/coverage for the yi'th scanline, going from
|
||||
// x0 to x1 in the horizontal direction (in 24.8 fixed point co-ordinates)
|
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// and from y0f to y1f fractional vertical units within that scanline.
|
||||
func (r *Rasterizer) scan(yi int, x0, y0f, x1, y1f Fixed) {
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// Break the 24.8 fixed point X co-ordinates into integral and fractional parts.
|
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x0i := int(x0) / 256
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||||
x0f := x0 - Fixed(256*x0i)
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x1i := int(x1) / 256
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x1f := x1 - Fixed(256*x1i)
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// A perfectly horizontal scan.
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if y0f == y1f {
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r.setCell(x1i, yi)
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||||
return
|
||||
}
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||||
dx, dy := x1-x0, y1f-y0f
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// A single cell scan.
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if x0i == x1i {
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r.area += int((x0f + x1f) * dy)
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r.cover += int(dy)
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return
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}
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// There are at least two cells. Apart from the first and last cells,
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// all intermediate cells go through the full width of the cell,
|
||||
// or 256 units in 24.8 fixed point format.
|
||||
var (
|
||||
p, q, edge0, edge1 Fixed
|
||||
xiDelta int
|
||||
)
|
||||
if dx > 0 {
|
||||
p, q = (256-x0f)*dy, dx
|
||||
edge0, edge1, xiDelta = 0, 256, 1
|
||||
} else {
|
||||
p, q = x0f*dy, -dx
|
||||
edge0, edge1, xiDelta = 256, 0, -1
|
||||
}
|
||||
yDelta, yRem := p/q, p%q
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||||
if yRem < 0 {
|
||||
yDelta -= 1
|
||||
yRem += q
|
||||
}
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||||
// Do the first cell.
|
||||
xi, y := x0i, y0f
|
||||
r.area += int((x0f + edge1) * yDelta)
|
||||
r.cover += int(yDelta)
|
||||
xi, y = xi+xiDelta, y+yDelta
|
||||
r.setCell(xi, yi)
|
||||
if xi != x1i {
|
||||
// Do all the intermediate cells.
|
||||
p = 256 * (y1f - y + yDelta)
|
||||
fullDelta, fullRem := p/q, p%q
|
||||
if fullRem < 0 {
|
||||
fullDelta -= 1
|
||||
fullRem += q
|
||||
}
|
||||
yRem -= q
|
||||
for xi != x1i {
|
||||
yDelta = fullDelta
|
||||
yRem += fullRem
|
||||
if yRem >= 0 {
|
||||
yDelta += 1
|
||||
yRem -= q
|
||||
}
|
||||
r.area += int(256 * yDelta)
|
||||
r.cover += int(yDelta)
|
||||
xi, y = xi+xiDelta, y+yDelta
|
||||
r.setCell(xi, yi)
|
||||
}
|
||||
}
|
||||
// Do the last cell.
|
||||
yDelta = y1f - y
|
||||
r.area += int((edge0 + x1f) * yDelta)
|
||||
r.cover += int(yDelta)
|
||||
}
|
||||
|
||||
// Start starts a new curve at the given point.
|
||||
func (r *Rasterizer) Start(a Point) {
|
||||
r.setCell(int(a.X/256), int(a.Y/256))
|
||||
r.a = a
|
||||
}
|
||||
|
||||
// Move1 adds a linear segment to the current curve.
|
||||
func (r *Rasterizer) Move1(b Point) {
|
||||
x0, y0 := r.a.X, r.a.Y
|
||||
x1, y1 := b.X, b.Y
|
||||
dx, dy := x1-x0, y1-y0
|
||||
// Break the 24.8 fixed point Y co-ordinates into integral and fractional parts.
|
||||
y0i := int(y0) / 256
|
||||
y0f := y0 - Fixed(256*y0i)
|
||||
y1i := int(y1) / 256
|
||||
y1f := y1 - Fixed(256*y1i)
|
||||
|
||||
if y0i == y1i {
|
||||
// There is only one scanline.
|
||||
r.scan(y0i, x0, y0f, x1, y1f)
|
||||
} else {
|
||||
// There are at least two scanlines. Apart from the first and last scanlines,
|
||||
// all intermediate scanlines go through the full height of the row, or 256
|
||||
// units in 24.8 fixed point format.
|
||||
var (
|
||||
p, q, edge0, edge1 Fixed
|
||||
yiDelta int
|
||||
)
|
||||
if dy > 0 {
|
||||
p, q = (256-y0f)*dx, dy
|
||||
edge0, edge1, yiDelta = 0, 256, 1
|
||||
} else {
|
||||
p, q = y0f*dx, -dy
|
||||
edge0, edge1, yiDelta = 256, 0, -1
|
||||
}
|
||||
xDelta, xRem := p/q, p%q
|
||||
if xRem < 0 {
|
||||
xDelta -= 1
|
||||
xRem += q
|
||||
}
|
||||
// Do the first scanline.
|
||||
x, yi := x0, y0i
|
||||
r.scan(yi, x, y0f, x+xDelta, edge1)
|
||||
x, yi = x+xDelta, yi+yiDelta
|
||||
r.setCell(int(x)/256, yi)
|
||||
if yi != y1i {
|
||||
// Do all the intermediate scanlines.
|
||||
p = 256 * dx
|
||||
fullDelta, fullRem := p/q, p%q
|
||||
if fullRem < 0 {
|
||||
fullDelta -= 1
|
||||
fullRem += q
|
||||
}
|
||||
xRem -= q
|
||||
for yi != y1i {
|
||||
xDelta = fullDelta
|
||||
xRem += fullRem
|
||||
if xRem >= 0 {
|
||||
xDelta += 1
|
||||
xRem -= q
|
||||
}
|
||||
r.scan(yi, x, edge0, x+xDelta, edge1)
|
||||
x, yi = x+xDelta, yi+yiDelta
|
||||
r.setCell(int(x)/256, yi)
|
||||
}
|
||||
}
|
||||
// Do the last scanline.
|
||||
r.scan(yi, x, edge0, x1, y1f)
|
||||
}
|
||||
// The next lineTo starts from b.
|
||||
r.a = b
|
||||
}
|
||||
|
||||
// Move2 adds a quadratic segment to the current curve.
|
||||
func (r *Rasterizer) Move2(b, c Point) {
|
||||
// Calculate nSplit (the number of recursive decompositions) based on how `curvy' it is.
|
||||
// Specifically, how much the middle point b deviates from (a+c)/2.
|
||||
dx := r.a.X - 2*b.X + c.X
|
||||
dy := r.a.Y - 2*b.Y + c.Y
|
||||
if dx < 0 {
|
||||
dx = -dx
|
||||
}
|
||||
if dy < 0 {
|
||||
dy = -dy
|
||||
}
|
||||
deviation := dx
|
||||
if deviation < dy {
|
||||
deviation = dy
|
||||
}
|
||||
nsplit := 0
|
||||
deviation /= Fixed(r.quadSplitScale)
|
||||
for deviation > 0 {
|
||||
deviation /= 4
|
||||
nsplit++
|
||||
}
|
||||
// maxd is 32-bit, and nsplit++ every time we shift off 2 bits, so maxNsplit is 16.
|
||||
const maxNsplit = 16
|
||||
if nsplit > maxNsplit {
|
||||
panic("freetype/raster: Move2 nsplit too large: " + strconv.Itoa(nsplit))
|
||||
}
|
||||
// Recursively decompose the curve nSplit levels deep.
|
||||
var (
|
||||
pStack [2*maxNsplit + 3]Point
|
||||
sStack [maxNsplit + 1]int
|
||||
i int
|
||||
)
|
||||
sStack[0] = nsplit
|
||||
pStack[0] = c
|
||||
pStack[1] = b
|
||||
pStack[2] = r.a
|
||||
for i >= 0 {
|
||||
s := sStack[i]
|
||||
if s > 0 {
|
||||
pp := pStack[2*i:]
|
||||
// Split the quadratic curve pp[0:3] into an equivalent set of two shorter curves:
|
||||
// pp[0:3] and pp[2:5]. The new pp[4] is the old pp[2], and pp[0] is unchanged.
|
||||
mx := pp[1].X
|
||||
pp[4].X = pp[2].X
|
||||
pp[3].X = (pp[4].X + mx) / 2
|
||||
pp[1].X = (pp[0].X + mx) / 2
|
||||
pp[2].X = (pp[1].X + pp[3].X) / 2
|
||||
my := pp[1].Y
|
||||
pp[4].Y = pp[2].Y
|
||||
pp[3].Y = (pp[4].Y + my) / 2
|
||||
pp[1].Y = (pp[0].Y + my) / 2
|
||||
pp[2].Y = (pp[1].Y + pp[3].Y) / 2
|
||||
// The two shorter curves have one less split to do.
|
||||
sStack[i] = s - 1
|
||||
sStack[i+1] = s - 1
|
||||
i++
|
||||
} else {
|
||||
// Replace the level-0 quadratic with a two-linear-piece approximation.
|
||||
midx := (r.a.X + 2*pStack[2*i+1].X + pStack[2*i].X) / 4
|
||||
midy := (r.a.Y + 2*pStack[2*i+1].Y + pStack[2*i].Y) / 4
|
||||
r.Move1(Point{midx, midy})
|
||||
r.Move1(pStack[2*i])
|
||||
i--
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// Move3 adds a cubic segment to the current curve.
|
||||
func (r *Rasterizer) Move3(b, c, d Point) {
|
||||
// TODO(nigeltao): implement cubic splines, similar to Move2's quadratic splines.
|
||||
panic("not implemented")
|
||||
}
|
||||
|
||||
// Converts an area value to a uint32 alpha value. A completely filled pixel
|
||||
// corresponds to an area of 256*256*2, and an alpha of 1<<32-1. The
|
||||
// conversion of area values greater than this depends on the winding rule:
|
||||
// even-odd or non-zero.
|
||||
func (r *Rasterizer) areaToAlpha(area int) uint32 {
|
||||
// The C Freetype implementation (version 2.3.12) does "alpha := area>>1" without
|
||||
// the +1. Round-to-nearest gives a more symmetric result than round-down.
|
||||
// The C implementation also returns 8-bit alpha, not 32-bit alpha.
|
||||
a := (area + 1) >> 1
|
||||
if a < 0 {
|
||||
a = -a
|
||||
}
|
||||
alpha := uint32(a)
|
||||
if r.UseNonZeroWinding {
|
||||
if alpha > 0xffff {
|
||||
alpha = 0xffff
|
||||
}
|
||||
} else {
|
||||
alpha &= 0x1ffff
|
||||
if alpha > 0x10000 {
|
||||
alpha = 0x20000 - alpha
|
||||
} else if alpha == 0x10000 {
|
||||
alpha = 0x0ffff
|
||||
}
|
||||
}
|
||||
alpha |= alpha << 16
|
||||
return alpha
|
||||
}
|
||||
|
||||
// Rasterize converts r's accumulated curves into spans for p. The spans
|
||||
// passed to p are non-overlapping, and sorted by Y and then X. They all
|
||||
// have non-zero width (and 0 <= xi0 < xi1 <= r.width) and non-zero alpha,
|
||||
// except for the final span, which has yi, xi0, xi1 and alpha all equal
|
||||
// to zero.
|
||||
func (r *Rasterizer) Rasterize(p Painter) {
|
||||
r.saveCell()
|
||||
for yi := 0; yi < len(r.cellIndex); yi++ {
|
||||
xi, cover := 0, 0
|
||||
for c := r.cellIndex[yi]; c != -1; c = r.cell[c].next {
|
||||
if cover != 0 && r.cell[c].xi > xi {
|
||||
alpha := r.areaToAlpha(cover * 256 * 2)
|
||||
if alpha != 0 {
|
||||
xi0, xi1 := xi, r.cell[c].xi
|
||||
if xi0 < 0 {
|
||||
xi0 = 0
|
||||
}
|
||||
if xi1 >= r.width {
|
||||
xi1 = r.width
|
||||
}
|
||||
if xi0 < xi1 {
|
||||
p.Paint(yi, xi0, xi1, alpha)
|
||||
}
|
||||
}
|
||||
}
|
||||
cover += r.cell[c].cover
|
||||
alpha := r.areaToAlpha(cover*256*2 - r.cell[c].area)
|
||||
xi = r.cell[c].xi + 1
|
||||
if alpha != 0 {
|
||||
xi0, xi1 := r.cell[c].xi, xi
|
||||
if xi0 < 0 {
|
||||
xi0 = 0
|
||||
}
|
||||
if xi1 >= r.width {
|
||||
xi1 = r.width
|
||||
}
|
||||
if xi0 < xi1 {
|
||||
p.Paint(yi, xi0, xi1, alpha)
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
p.Paint(0, 0, 0, 0)
|
||||
}
|
||||
|
||||
// Clear cancels any previous calls to r.Start or r.MoveN.
|
||||
func (r *Rasterizer) Clear() {
|
||||
r.a = Point{0, 0}
|
||||
r.xi = 0
|
||||
r.yi = 0
|
||||
r.area = 0
|
||||
r.cover = 0
|
||||
r.cell = r.cell[0:0]
|
||||
for i := 0; i < len(r.cellIndex); i++ {
|
||||
r.cellIndex[i] = -1
|
||||
}
|
||||
}
|
||||
|
||||
// Creates a new Rasterizer with the given bounds.
|
||||
func New(width, height int) *Rasterizer {
|
||||
if width < 0 {
|
||||
width = 0
|
||||
}
|
||||
if height < 0 {
|
||||
height = 0
|
||||
}
|
||||
|
||||
// Use the same qss heuristic as the C Freetype implementation.
|
||||
qss := 128
|
||||
if width > 24 || height > 24 {
|
||||
qss *= 2
|
||||
if width > 120 || height > 120 {
|
||||
qss *= 2
|
||||
}
|
||||
}
|
||||
|
||||
r := new(Rasterizer)
|
||||
r.width = width
|
||||
r.quadSplitScale = qss
|
||||
r.cell = r.cellBuf[0:0]
|
||||
if height > len(r.cellIndexBuf) {
|
||||
r.cellIndex = make([]int, height)
|
||||
} else {
|
||||
r.cellIndex = r.cellIndexBuf[0:height]
|
||||
}
|
||||
for i := 0; i < len(r.cellIndex); i++ {
|
||||
r.cellIndex[i] = -1
|
||||
}
|
||||
return r
|
||||
}
|
||||
|
||||
// AlphaOverPainter returns a Painter that paints onto the given Alpha image
|
||||
// using the "src over dst" Porter-Duff composition operator.
|
||||
func AlphaOverPainter(m *image.Alpha) Painter {
|
||||
return PainterFunc(func(yi, xi0, xi1 int, alpha uint32) {
|
||||
a := int(alpha >> 24)
|
||||
p := m.Pixel[yi]
|
||||
for i := xi0; i < xi1; i++ {
|
||||
ai := int(p[i].A)
|
||||
ai = (ai*255 + (255-ai)*a) / 255
|
||||
p[i] = image.AlphaColor{uint8(ai)}
|
||||
}
|
||||
})
|
||||
}
|
||||
|
||||
// AlphaSrcPainter returns a Painter that paints onto the given Alpha image
|
||||
// using the "src" Porter-Duff composition operator.
|
||||
func AlphaSrcPainter(m *image.Alpha) Painter {
|
||||
return PainterFunc(func(yi, xi0, xi1 int, alpha uint32) {
|
||||
color := image.AlphaColor{uint8(alpha >> 24)}
|
||||
p := m.Pixel[yi]
|
||||
for i := xi0; i < xi1; i++ {
|
||||
p[i] = color
|
||||
}
|
||||
})
|
||||
}
|
169
licenses/ftl.txt
Normal file
169
licenses/ftl.txt
Normal file
|
@ -0,0 +1,169 @@
|
|||
The FreeType Project LICENSE
|
||||
----------------------------
|
||||
|
||||
2006-Jan-27
|
||||
|
||||
Copyright 1996-2002, 2006 by
|
||||
David Turner, Robert Wilhelm, and Werner Lemberg
|
||||
|
||||
|
||||
|
||||
Introduction
|
||||
============
|
||||
|
||||
The FreeType Project is distributed in several archive packages;
|
||||
some of them may contain, in addition to the FreeType font engine,
|
||||
various tools and contributions which rely on, or relate to, the
|
||||
FreeType Project.
|
||||
|
||||
This license applies to all files found in such packages, and
|
||||
which do not fall under their own explicit license. The license
|
||||
affects thus the FreeType font engine, the test programs,
|
||||
documentation and makefiles, at the very least.
|
||||
|
||||
This license was inspired by the BSD, Artistic, and IJG
|
||||
(Independent JPEG Group) licenses, which all encourage inclusion
|
||||
and use of free software in commercial and freeware products
|
||||
alike. As a consequence, its main points are that:
|
||||
|
||||
o We don't promise that this software works. However, we will be
|
||||
interested in any kind of bug reports. (`as is' distribution)
|
||||
|
||||
o You can use this software for whatever you want, in parts or
|
||||
full form, without having to pay us. (`royalty-free' usage)
|
||||
|
||||
o You may not pretend that you wrote this software. If you use
|
||||
it, or only parts of it, in a program, you must acknowledge
|
||||
somewhere in your documentation that you have used the
|
||||
FreeType code. (`credits')
|
||||
|
||||
We specifically permit and encourage the inclusion of this
|
||||
software, with or without modifications, in commercial products.
|
||||
We disclaim all warranties covering The FreeType Project and
|
||||
assume no liability related to The FreeType Project.
|
||||
|
||||
|
||||
Finally, many people asked us for a preferred form for a
|
||||
credit/disclaimer to use in compliance with this license. We thus
|
||||
encourage you to use the following text:
|
||||
|
||||
"""
|
||||
Portions of this software are copyright © <year> The FreeType
|
||||
Project (www.freetype.org). All rights reserved.
|
||||
"""
|
||||
|
||||
Please replace <year> with the value from the FreeType version you
|
||||
actually use.
|
||||
|
||||
|
||||
Legal Terms
|
||||
===========
|
||||
|
||||
0. Definitions
|
||||
--------------
|
||||
|
||||
Throughout this license, the terms `package', `FreeType Project',
|
||||
and `FreeType archive' refer to the set of files originally
|
||||
distributed by the authors (David Turner, Robert Wilhelm, and
|
||||
Werner Lemberg) as the `FreeType Project', be they named as alpha,
|
||||
beta or final release.
|
||||
|
||||
`You' refers to the licensee, or person using the project, where
|
||||
`using' is a generic term including compiling the project's source
|
||||
code as well as linking it to form a `program' or `executable'.
|
||||
This program is referred to as `a program using the FreeType
|
||||
engine'.
|
||||
|
||||
This license applies to all files distributed in the original
|
||||
FreeType Project, including all source code, binaries and
|
||||
documentation, unless otherwise stated in the file in its
|
||||
original, unmodified form as distributed in the original archive.
|
||||
If you are unsure whether or not a particular file is covered by
|
||||
this license, you must contact us to verify this.
|
||||
|
||||
The FreeType Project is copyright (C) 1996-2000 by David Turner,
|
||||
Robert Wilhelm, and Werner Lemberg. All rights reserved except as
|
||||
specified below.
|
||||
|
||||
1. No Warranty
|
||||
--------------
|
||||
|
||||
THE FREETYPE PROJECT IS PROVIDED `AS IS' WITHOUT WARRANTY OF ANY
|
||||
KIND, EITHER EXPRESS OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
|
||||
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
|
||||
PURPOSE. IN NO EVENT WILL ANY OF THE AUTHORS OR COPYRIGHT HOLDERS
|
||||
BE LIABLE FOR ANY DAMAGES CAUSED BY THE USE OR THE INABILITY TO
|
||||
USE, OF THE FREETYPE PROJECT.
|
||||
|
||||
2. Redistribution
|
||||
-----------------
|
||||
|
||||
This license grants a worldwide, royalty-free, perpetual and
|
||||
irrevocable right and license to use, execute, perform, compile,
|
||||
display, copy, create derivative works of, distribute and
|
||||
sublicense the FreeType Project (in both source and object code
|
||||
forms) and derivative works thereof for any purpose; and to
|
||||
authorize others to exercise some or all of the rights granted
|
||||
herein, subject to the following conditions:
|
||||
|
||||
o Redistribution of source code must retain this license file
|
||||
(`FTL.TXT') unaltered; any additions, deletions or changes to
|
||||
the original files must be clearly indicated in accompanying
|
||||
documentation. The copyright notices of the unaltered,
|
||||
original files must be preserved in all copies of source
|
||||
files.
|
||||
|
||||
o Redistribution in binary form must provide a disclaimer that
|
||||
states that the software is based in part of the work of the
|
||||
FreeType Team, in the distribution documentation. We also
|
||||
encourage you to put an URL to the FreeType web page in your
|
||||
documentation, though this isn't mandatory.
|
||||
|
||||
These conditions apply to any software derived from or based on
|
||||
the FreeType Project, not just the unmodified files. If you use
|
||||
our work, you must acknowledge us. However, no fee need be paid
|
||||
to us.
|
||||
|
||||
3. Advertising
|
||||
--------------
|
||||
|
||||
Neither the FreeType authors and contributors nor you shall use
|
||||
the name of the other for commercial, advertising, or promotional
|
||||
purposes without specific prior written permission.
|
||||
|
||||
We suggest, but do not require, that you use one or more of the
|
||||
following phrases to refer to this software in your documentation
|
||||
or advertising materials: `FreeType Project', `FreeType Engine',
|
||||
`FreeType library', or `FreeType Distribution'.
|
||||
|
||||
As you have not signed this license, you are not required to
|
||||
accept it. However, as the FreeType Project is copyrighted
|
||||
material, only this license, or another one contracted with the
|
||||
authors, grants you the right to use, distribute, and modify it.
|
||||
Therefore, by using, distributing, or modifying the FreeType
|
||||
Project, you indicate that you understand and accept all the terms
|
||||
of this license.
|
||||
|
||||
4. Contacts
|
||||
-----------
|
||||
|
||||
There are two mailing lists related to FreeType:
|
||||
|
||||
o freetype@nongnu.org
|
||||
|
||||
Discusses general use and applications of FreeType, as well as
|
||||
future and wanted additions to the library and distribution.
|
||||
If you are looking for support, start in this list if you
|
||||
haven't found anything to help you in the documentation.
|
||||
|
||||
o freetype-devel@nongnu.org
|
||||
|
||||
Discusses bugs, as well as engine internals, design issues,
|
||||
specific licenses, porting, etc.
|
||||
|
||||
Our home page can be found at
|
||||
|
||||
http://www.freetype.org
|
||||
|
||||
|
||||
--- end of FTL.TXT ---
|
340
licenses/gpl.txt
Normal file
340
licenses/gpl.txt
Normal file
|
@ -0,0 +1,340 @@
|
|||
GNU GENERAL PUBLIC LICENSE
|
||||
Version 2, June 1991
|
||||
|
||||
Copyright (C) 1989, 1991 Free Software Foundation, Inc.
|
||||
51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
||||
Everyone is permitted to copy and distribute verbatim copies
|
||||
of this license document, but changing it is not allowed.
|
||||
|
||||
Preamble
|
||||
|
||||
The licenses for most software are designed to take away your
|
||||
freedom to share and change it. By contrast, the GNU General Public
|
||||
License is intended to guarantee your freedom to share and change free
|
||||
software--to make sure the software is free for all its users. This
|
||||
General Public License applies to most of the Free Software
|
||||
Foundation's software and to any other program whose authors commit to
|
||||
using it. (Some other Free Software Foundation software is covered by
|
||||
the GNU Library General Public License instead.) You can apply it to
|
||||
your programs, too.
|
||||
|
||||
When we speak of free software, we are referring to freedom, not
|
||||
price. Our General Public Licenses are designed to make sure that you
|
||||
have the freedom to distribute copies of free software (and charge for
|
||||
this service if you wish), that you receive source code or can get it
|
||||
if you want it, that you can change the software or use pieces of it
|
||||
in new free programs; and that you know you can do these things.
|
||||
|
||||
To protect your rights, we need to make restrictions that forbid
|
||||
anyone to deny you these rights or to ask you to surrender the rights.
|
||||
These restrictions translate to certain responsibilities for you if you
|
||||
distribute copies of the software, or if you modify it.
|
||||
|
||||
For example, if you distribute copies of such a program, whether
|
||||
gratis or for a fee, you must give the recipients all the rights that
|
||||
you have. You must make sure that they, too, receive or can get the
|
||||
source code. And you must show them these terms so they know their
|
||||
rights.
|
||||
|
||||
We protect your rights with two steps: (1) copyright the software, and
|
||||
(2) offer you this license which gives you legal permission to copy,
|
||||
distribute and/or modify the software.
|
||||
|
||||
Also, for each author's protection and ours, we want to make certain
|
||||
that everyone understands that there is no warranty for this free
|
||||
software. If the software is modified by someone else and passed on, we
|
||||
want its recipients to know that what they have is not the original, so
|
||||
that any problems introduced by others will not reflect on the original
|
||||
authors' reputations.
|
||||
|
||||
Finally, any free program is threatened constantly by software
|
||||
patents. We wish to avoid the danger that redistributors of a free
|
||||
program will individually obtain patent licenses, in effect making the
|
||||
program proprietary. To prevent this, we have made it clear that any
|
||||
patent must be licensed for everyone's free use or not licensed at all.
|
||||
|
||||
The precise terms and conditions for copying, distribution and
|
||||
modification follow.
|
||||
|
||||
GNU GENERAL PUBLIC LICENSE
|
||||
TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
|
||||
|
||||
0. This License applies to any program or other work which contains
|
||||
a notice placed by the copyright holder saying it may be distributed
|
||||
under the terms of this General Public License. The "Program", below,
|
||||
refers to any such program or work, and a "work based on the Program"
|
||||
means either the Program or any derivative work under copyright law:
|
||||
that is to say, a work containing the Program or a portion of it,
|
||||
either verbatim or with modifications and/or translated into another
|
||||
language. (Hereinafter, translation is included without limitation in
|
||||
the term "modification".) Each licensee is addressed as "you".
|
||||
|
||||
Activities other than copying, distribution and modification are not
|
||||
covered by this License; they are outside its scope. The act of
|
||||
running the Program is not restricted, and the output from the Program
|
||||
is covered only if its contents constitute a work based on the
|
||||
Program (independent of having been made by running the Program).
|
||||
Whether that is true depends on what the Program does.
|
||||
|
||||
1. You may copy and distribute verbatim copies of the Program's
|
||||
source code as you receive it, in any medium, provided that you
|
||||
conspicuously and appropriately publish on each copy an appropriate
|
||||
copyright notice and disclaimer of warranty; keep intact all the
|
||||
notices that refer to this License and to the absence of any warranty;
|
||||
and give any other recipients of the Program a copy of this License
|
||||
along with the Program.
|
||||
|
||||
You may charge a fee for the physical act of transferring a copy, and
|
||||
you may at your option offer warranty protection in exchange for a fee.
|
||||
|
||||
2. You may modify your copy or copies of the Program or any portion
|
||||
of it, thus forming a work based on the Program, and copy and
|
||||
distribute such modifications or work under the terms of Section 1
|
||||
above, provided that you also meet all of these conditions:
|
||||
|
||||
a) You must cause the modified files to carry prominent notices
|
||||
stating that you changed the files and the date of any change.
|
||||
|
||||
b) You must cause any work that you distribute or publish, that in
|
||||
whole or in part contains or is derived from the Program or any
|
||||
part thereof, to be licensed as a whole at no charge to all third
|
||||
parties under the terms of this License.
|
||||
|
||||
c) If the modified program normally reads commands interactively
|
||||
when run, you must cause it, when started running for such
|
||||
interactive use in the most ordinary way, to print or display an
|
||||
announcement including an appropriate copyright notice and a
|
||||
notice that there is no warranty (or else, saying that you provide
|
||||
a warranty) and that users may redistribute the program under
|
||||
these conditions, and telling the user how to view a copy of this
|
||||
License. (Exception: if the Program itself is interactive but
|
||||
does not normally print such an announcement, your work based on
|
||||
the Program is not required to print an announcement.)
|
||||
|
||||
These requirements apply to the modified work as a whole. If
|
||||
identifiable sections of that work are not derived from the Program,
|
||||
and can be reasonably considered independent and separate works in
|
||||
themselves, then this License, and its terms, do not apply to those
|
||||
sections when you distribute them as separate works. But when you
|
||||
distribute the same sections as part of a whole which is a work based
|
||||
on the Program, the distribution of the whole must be on the terms of
|
||||
this License, whose permissions for other licensees extend to the
|
||||
entire whole, and thus to each and every part regardless of who wrote it.
|
||||
|
||||
Thus, it is not the intent of this section to claim rights or contest
|
||||
your rights to work written entirely by you; rather, the intent is to
|
||||
exercise the right to control the distribution of derivative or
|
||||
collective works based on the Program.
|
||||
|
||||
In addition, mere aggregation of another work not based on the Program
|
||||
with the Program (or with a work based on the Program) on a volume of
|
||||
a storage or distribution medium does not bring the other work under
|
||||
the scope of this License.
|
||||
|
||||
3. You may copy and distribute the Program (or a work based on it,
|
||||
under Section 2) in object code or executable form under the terms of
|
||||
Sections 1 and 2 above provided that you also do one of the following:
|
||||
|
||||
a) Accompany it with the complete corresponding machine-readable
|
||||
source code, which must be distributed under the terms of Sections
|
||||
1 and 2 above on a medium customarily used for software interchange; or,
|
||||
|
||||
b) Accompany it with a written offer, valid for at least three
|
||||
years, to give any third party, for a charge no more than your
|
||||
cost of physically performing source distribution, a complete
|
||||
machine-readable copy of the corresponding source code, to be
|
||||
distributed under the terms of Sections 1 and 2 above on a medium
|
||||
customarily used for software interchange; or,
|
||||
|
||||
c) Accompany it with the information you received as to the offer
|
||||
to distribute corresponding source code. (This alternative is
|
||||
allowed only for noncommercial distribution and only if you
|
||||
received the program in object code or executable form with such
|
||||
an offer, in accord with Subsection b above.)
|
||||
|
||||
The source code for a work means the preferred form of the work for
|
||||
making modifications to it. For an executable work, complete source
|
||||
code means all the source code for all modules it contains, plus any
|
||||
associated interface definition files, plus the scripts used to
|
||||
control compilation and installation of the executable. However, as a
|
||||
special exception, the source code distributed need not include
|
||||
anything that is normally distributed (in either source or binary
|
||||
form) with the major components (compiler, kernel, and so on) of the
|
||||
operating system on which the executable runs, unless that component
|
||||
itself accompanies the executable.
|
||||
|
||||
If distribution of executable or object code is made by offering
|
||||
access to copy from a designated place, then offering equivalent
|
||||
access to copy the source code from the same place counts as
|
||||
distribution of the source code, even though third parties are not
|
||||
compelled to copy the source along with the object code.
|
||||
|
||||
4. You may not copy, modify, sublicense, or distribute the Program
|
||||
except as expressly provided under this License. Any attempt
|
||||
otherwise to copy, modify, sublicense or distribute the Program is
|
||||
void, and will automatically terminate your rights under this License.
|
||||
However, parties who have received copies, or rights, from you under
|
||||
this License will not have their licenses terminated so long as such
|
||||
parties remain in full compliance.
|
||||
|
||||
5. You are not required to accept this License, since you have not
|
||||
signed it. However, nothing else grants you permission to modify or
|
||||
distribute the Program or its derivative works. These actions are
|
||||
prohibited by law if you do not accept this License. Therefore, by
|
||||
modifying or distributing the Program (or any work based on the
|
||||
Program), you indicate your acceptance of this License to do so, and
|
||||
all its terms and conditions for copying, distributing or modifying
|
||||
the Program or works based on it.
|
||||
|
||||
6. Each time you redistribute the Program (or any work based on the
|
||||
Program), the recipient automatically receives a license from the
|
||||
original licensor to copy, distribute or modify the Program subject to
|
||||
these terms and conditions. You may not impose any further
|
||||
restrictions on the recipients' exercise of the rights granted herein.
|
||||
You are not responsible for enforcing compliance by third parties to
|
||||
this License.
|
||||
|
||||
7. If, as a consequence of a court judgment or allegation of patent
|
||||
infringement or for any other reason (not limited to patent issues),
|
||||
conditions are imposed on you (whether by court order, agreement or
|
||||
otherwise) that contradict the conditions of this License, they do not
|
||||
excuse you from the conditions of this License. If you cannot
|
||||
distribute so as to satisfy simultaneously your obligations under this
|
||||
License and any other pertinent obligations, then as a consequence you
|
||||
may not distribute the Program at all. For example, if a patent
|
||||
license would not permit royalty-free redistribution of the Program by
|
||||
all those who receive copies directly or indirectly through you, then
|
||||
the only way you could satisfy both it and this License would be to
|
||||
refrain entirely from distribution of the Program.
|
||||
|
||||
If any portion of this section is held invalid or unenforceable under
|
||||
any particular circumstance, the balance of the section is intended to
|
||||
apply and the section as a whole is intended to apply in other
|
||||
circumstances.
|
||||
|
||||
It is not the purpose of this section to induce you to infringe any
|
||||
patents or other property right claims or to contest validity of any
|
||||
such claims; this section has the sole purpose of protecting the
|
||||
integrity of the free software distribution system, which is
|
||||
implemented by public license practices. Many people have made
|
||||
generous contributions to the wide range of software distributed
|
||||
through that system in reliance on consistent application of that
|
||||
system; it is up to the author/donor to decide if he or she is willing
|
||||
to distribute software through any other system and a licensee cannot
|
||||
impose that choice.
|
||||
|
||||
This section is intended to make thoroughly clear what is believed to
|
||||
be a consequence of the rest of this License.
|
||||
|
||||
8. If the distribution and/or use of the Program is restricted in
|
||||
certain countries either by patents or by copyrighted interfaces, the
|
||||
original copyright holder who places the Program under this License
|
||||
may add an explicit geographical distribution limitation excluding
|
||||
those countries, so that distribution is permitted only in or among
|
||||
countries not thus excluded. In such case, this License incorporates
|
||||
the limitation as if written in the body of this License.
|
||||
|
||||
9. The Free Software Foundation may publish revised and/or new versions
|
||||
of the General Public License from time to time. Such new versions will
|
||||
be similar in spirit to the present version, but may differ in detail to
|
||||
address new problems or concerns.
|
||||
|
||||
Each version is given a distinguishing version number. If the Program
|
||||
specifies a version number of this License which applies to it and "any
|
||||
later version", you have the option of following the terms and conditions
|
||||
either of that version or of any later version published by the Free
|
||||
Software Foundation. If the Program does not specify a version number of
|
||||
this License, you may choose any version ever published by the Free Software
|
||||
Foundation.
|
||||
|
||||
10. If you wish to incorporate parts of the Program into other free
|
||||
programs whose distribution conditions are different, write to the author
|
||||
to ask for permission. For software which is copyrighted by the Free
|
||||
Software Foundation, write to the Free Software Foundation; we sometimes
|
||||
make exceptions for this. Our decision will be guided by the two goals
|
||||
of preserving the free status of all derivatives of our free software and
|
||||
of promoting the sharing and reuse of software generally.
|
||||
|
||||
NO WARRANTY
|
||||
|
||||
11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
|
||||
FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN
|
||||
OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
|
||||
PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
|
||||
OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
|
||||
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS
|
||||
TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE
|
||||
PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
|
||||
REPAIR OR CORRECTION.
|
||||
|
||||
12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
|
||||
WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
|
||||
REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
|
||||
INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
|
||||
OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
|
||||
TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
|
||||
YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
|
||||
PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
|
||||
POSSIBILITY OF SUCH DAMAGES.
|
||||
|
||||
END OF TERMS AND CONDITIONS
|
||||
|
||||
How to Apply These Terms to Your New Programs
|
||||
|
||||
If you develop a new program, and you want it to be of the greatest
|
||||
possible use to the public, the best way to achieve this is to make it
|
||||
free software which everyone can redistribute and change under these terms.
|
||||
|
||||
To do so, attach the following notices to the program. It is safest
|
||||
to attach them to the start of each source file to most effectively
|
||||
convey the exclusion of warranty; and each file should have at least
|
||||
the "copyright" line and a pointer to where the full notice is found.
|
||||
|
||||
<one line to give the program's name and a brief idea of what it does.>
|
||||
Copyright (C) <year> <name of author>
|
||||
|
||||
This program is free software; you can redistribute it and/or modify
|
||||
it under the terms of the GNU General Public License as published by
|
||||
the Free Software Foundation; either version 2 of the License, or
|
||||
(at your option) any later version.
|
||||
|
||||
This program is distributed in the hope that it will be useful,
|
||||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
GNU General Public License for more details.
|
||||
|
||||
You should have received a copy of the GNU General Public License
|
||||
along with this program; if not, write to the Free Software
|
||||
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
||||
|
||||
|
||||
Also add information on how to contact you by electronic and paper mail.
|
||||
|
||||
If the program is interactive, make it output a short notice like this
|
||||
when it starts in an interactive mode:
|
||||
|
||||
Gnomovision version 69, Copyright (C) year name of author
|
||||
Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
|
||||
This is free software, and you are welcome to redistribute it
|
||||
under certain conditions; type `show c' for details.
|
||||
|
||||
The hypothetical commands `show w' and `show c' should show the appropriate
|
||||
parts of the General Public License. Of course, the commands you use may
|
||||
be called something other than `show w' and `show c'; they could even be
|
||||
mouse-clicks or menu items--whatever suits your program.
|
||||
|
||||
You should also get your employer (if you work as a programmer) or your
|
||||
school, if any, to sign a "copyright disclaimer" for the program, if
|
||||
necessary. Here is a sample; alter the names:
|
||||
|
||||
Yoyodyne, Inc., hereby disclaims all copyright interest in the program
|
||||
`Gnomovision' (which makes passes at compilers) written by James Hacker.
|
||||
|
||||
<signature of Ty Coon>, 1 April 1989
|
||||
Ty Coon, President of Vice
|
||||
|
||||
This General Public License does not permit incorporating your program into
|
||||
proprietary programs. If your program is a subroutine library, you may
|
||||
consider it more useful to permit linking proprietary applications with the
|
||||
library. If this is what you want to do, use the GNU Library General
|
||||
Public License instead of this License.
|
Loading…
Reference in New Issue
Block a user