/usr/include/thunderbird/mozilla/gfx/BezierUtils.h is in thunderbird-dev 1:52.8.0-1~deb8u1.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 | /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef mozilla_BezierUtils_h_
#define mozilla_BezierUtils_h_
#include "mozilla/gfx/2D.h"
#include "gfxRect.h"
namespace mozilla {
namespace gfx {
// Control points for bezier curve
//
// mPoints[2]
// +-----___---+ mPoints[3]
// __--
// _--
// /
// /
// mPoints[1] + |
// | |
// ||
// ||
// |
// |
// |
// |
// mPoints[0] +
struct Bezier {
Point mPoints[4];
};
// Calculate a point or it's differential of a bezier curve formed by
// aBezier and parameter t.
//
// GetBezierPoint = P(t)
// GetBezierDifferential = P'(t)
// GetBezierDifferential2 = P''(t)
//
// mPoints[2]
// +-----___---+ mPoints[3]
// __-- P(1)
// _--
// +
// / P(t)
// mPoints[1] + |
// | |
// ||
// ||
// |
// |
// |
// |
// mPoints[0] + P(0)
Point GetBezierPoint(const Bezier& aBezier, Float t);
Point GetBezierDifferential(const Bezier& aBezier, Float t);
Point GetBezierDifferential2(const Bezier& aBezier, Float t);
// Calculate length of a simple bezier curve formed by aBezier and range [a, b].
Float GetBezierLength(const Bezier& aBezier, Float a, Float b);
// Split bezier curve formed by aBezier into [0,t1], [t1,t2], [t2,1] parts, and
// stores control points for [t1,t2] to aSubBezier.
//
// ___---+
// __+- P(1)
// _-- P(t2)
// -
// / <-- aSubBezier
// |
// |
// +
// | P(t1)
// |
// |
// |
// |
// + P(0)
void GetSubBezier(Bezier* aSubBezier, const Bezier& aBezier,
Float t1, Float t2);
// Find a nearest point on bezier curve formed by aBezier to a point aTarget.
// aInitialT is a hint to find the parameter t for the nearest point.
// If aT is non-null, parameter for the nearest point is stored to *aT.
// This function expects a bezier curve to be an approximation of elliptic arc.
// Otherwise it will return wrong point.
//
// aTarget
// + ___---+
// __--
// _--
// +
// / nearest point = P(t = *aT)
// |
// |
// |
// + P(aInitialT)
// |
// |
// |
// |
// +
Point FindBezierNearestPoint(const Bezier& aBezier, const Point& aTarget,
Float aInitialT, Float* aT=nullptr);
// Calculate control points for a bezier curve that is an approximation of
// an elliptic arc.
//
// aCornerSize.width
// |<----------------->|
// | |
// aCornerPoint| mPoints[2] |
// -------------+-------+-----___---+ mPoints[3]
// ^ | __--
// | | _--
// | | -
// | | /
// aCornerSize.height | mPoints[1] + |
// | | |
// | ||
// | ||
// | |
// | |
// | |
// v mPoints[0] |
// -------------+
void GetBezierPointsForCorner(Bezier* aBezier, mozilla::css::Corner aCorner,
const Point& aCornerPoint,
const Size& aCornerSize);
// Calculate the approximate length of a quarter elliptic arc formed by radii
// (a, b).
//
// a
// |<----------------->|
// | |
// ---+-------------___---+
// ^ | __--
// | | _--
// | | -
// | | /
// b | | |
// | | |
// | ||
// | ||
// | |
// | |
// | |
// v |
// ---+
Float GetQuarterEllipticArcLength(Float a, Float b);
// Calculate the distance between an elliptic arc formed by (origin, width,
// height), and a point P, along a line formed by |P + n * normal|.
// P should be outside of the ellipse, and the line should cross with the
// ellipse twice at n > 0 points.
//
// width
// |<----------------->|
// origin | |
// -----------+-------------___---+
// ^ normal | __--
// | P +->__ | _--
// | --__ -
// | | --+
// height | | |
// | | |
// | ||
// | ||
// | |
// | |
// | |
// v |
// -----------+
Float CalculateDistanceToEllipticArc(const Point& P, const Point& normal,
const Point& origin,
Float width, Float height);
} // namespace gfx
} // namespace mozilla
#endif /* mozilla_BezierUtils_h_ */
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