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#include "CurveIntersection.h"
#include "Extrema.h"
static int isBoundedByEndPoints(double a, double b, double c)
{
return (a <= b && b <= c) || (a >= b && b >= c);
}
double leftMostT(const Quadratic& quad, double startT, double endT) {
double leftT;
if (findExtrema(quad[0].x, quad[1].x, quad[2].x, &leftT)
&& startT <= leftT && leftT <= endT) {
return leftT;
}
_Point startPt;
xy_at_t(quad, startT, startPt.x, startPt.y);
_Point endPt;
xy_at_t(quad, endT, endPt.x, endPt.y);
return startPt.x <= endPt.x ? startT : endT;
}
void _Rect::setBounds(const Quadratic& quad) {
set(quad[0]);
add(quad[2]);
double tValues[2];
int roots = 0;
if (!isBoundedByEndPoints(quad[0].x, quad[1].x, quad[2].x)) {
roots = findExtrema(quad[0].x, quad[1].x, quad[2].x, tValues);
}
if (!isBoundedByEndPoints(quad[0].y, quad[1].y, quad[2].y)) {
roots += findExtrema(quad[0].y, quad[1].y, quad[2].y,
&tValues[roots]);
}
for (int x = 0; x < roots; ++x) {
_Point result;
xy_at_t(quad, tValues[x], result.x, result.y);
add(result);
}
}
void _Rect::setRawBounds(const Quadratic& quad) {
set(quad[0]);
for (int x = 1; x < 3; ++x) {
add(quad[x]);
}
}
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