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caryclark@google.com8dcf1142012-07-02 20:27:02 +00001#include "DataTypes.h"
2
3void dxdy_at_t(const Quadratic& , double t, double& x, double& y);
4
caryclark@google.com639df892012-01-10 21:46:10 +00005/* Parameterization form, given A*t*t + 2*B*t*(1-t) + C*(1-t)*(1-t)
6 *
7 * a = A - 2*B + C
8 * b = 2*B - 2*C
9 * c = C
10 */
caryclark@google.com27accef2012-01-25 18:57:23 +000011inline void set_abc(const double* quad, double& a, double& b, double& c) {
caryclark@google.com639df892012-01-10 21:46:10 +000012 a = quad[0]; // a = A
13 b = 2 * quad[2]; // b = 2*B
14 c = quad[4]; // c = C
15 b -= c; // b = 2*B - C
16 a -= b; // a = A - 2*B + C
17 b -= c; // b = 2*B - 2*C
18}
caryclark@google.com27accef2012-01-25 18:57:23 +000019
20int quadraticRoots(double A, double B, double C, double t[2]);
caryclark@google.com8dcf1142012-07-02 20:27:02 +000021
22void xy_at_t(const Quadratic& , double t, double& x, double& y);