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caryclark@google.comc6825902012-02-03 22:07:47 +00001#include "CurveIntersection.h"
caryclark@google.com27accef2012-01-25 18:57:23 +00002#include "LineUtilities.h"
3
4bool implicitLine(const _Line& line, double& slope, double& axisIntercept) {
caryclark@google.comc6825902012-02-03 22:07:47 +00005 _Point delta;
6 tangent(line, delta);
7 bool moreHorizontal = fabs(delta.x) > fabs(delta.y);
caryclark@google.com27accef2012-01-25 18:57:23 +00008 if (moreHorizontal) {
caryclark@google.comc6825902012-02-03 22:07:47 +00009 slope = delta.y / delta.x;
caryclark@google.com27accef2012-01-25 18:57:23 +000010 axisIntercept = line[0].y - slope * line[0].x;
11 } else {
caryclark@google.comc6825902012-02-03 22:07:47 +000012 slope = delta.x / delta.y;
caryclark@google.com27accef2012-01-25 18:57:23 +000013 axisIntercept = line[0].x - slope * line[0].y;
14 }
15 return moreHorizontal;
16}
17
18int reduceOrder(const _Line& line, _Line& reduced) {
19 reduced[0] = line[0];
20 int different = line[0] != line[1];
21 reduced[1] = line[different];
22 return 1 + different;
23}