9e49fb63d3
add copyrights everywhere start working on quadratic line segments (for quad intersection) git-svn-id: http://skia.googlecode.com/svn/trunk@5286 2bbb7eff-a529-9590-31e7-b0007b416f81
29 lines
815 B
C
29 lines
815 B
C
/*
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* Copyright 2012 Google Inc.
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*
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* Use of this source code is governed by a BSD-style license that can be
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* found in the LICENSE file.
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*/
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#include "DataTypes.h"
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void dxdy_at_t(const Quadratic& , double t, double& x, double& y);
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/* Parameterization form, given A*t*t + 2*B*t*(1-t) + C*(1-t)*(1-t)
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*
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* a = A - 2*B + C
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* b = 2*B - 2*C
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* c = C
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*/
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inline void set_abc(const double* quad, double& a, double& b, double& c) {
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a = quad[0]; // a = A
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b = 2 * quad[2]; // b = 2*B
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c = quad[4]; // c = C
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b -= c; // b = 2*B - C
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a -= b; // a = A - 2*B + C
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b -= c; // b = 2*B - 2*C
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}
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int quadraticRoots(double A, double B, double C, double t[2]);
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void xy_at_t(const Quadratic& , double t, double& x, double& y);
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