xiaoyan159/vtm
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

more line intersection utilities

Browse Source
This commit is contained in:
Hannes Janetzek 2013-01-10 06:57:42 +01:00
parent 1c11cd1780
commit 82eb7e4973
1 changed files with 39 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

39
src/org/oscim/utils/GeometryUtils.java
View File

@ -185,4 +185,43 @@ public final class GeometryUtils {
return Math.abs((P.x - A.x) * (B.y - A.y) - (P.y - A.y) * (B.x - A.x)) / normalLength; return Math.abs((P.x - A.x) * (B.y - A.y) - (P.y - A.y) * (B.x - A.x)) / normalLength;
} }
public static final class Point2D {
public double x;
public double y;
}
// from libosmscout-render
public static byte calcLinesIntersect(
double ax1, double ay1,
double ax2, double ay2,
double bx1, double by1,
double bx2, double by2,
GeometryUtils.Point2D point)
{
double ua_numr = (bx2 - bx1) * (ay1 - by1) - (by2 - by1) * (ax1 - bx1);
double ub_numr = (ax2 - ax1) * (ay1 - by1) - (ay2 - ay1) * (ax1 - bx1);
double denr = (by2 - by1) * (ax2 - ax1) - (bx2 - bx1) * (ay2 - ay1);
if (denr == 0.0)
{
// lines are coincident
if (ua_numr == 0.0 && ub_numr == 0.0)
return 2; //XSEC_COINCIDENT;
// lines are parallel
return 3; //XSEC_PARALLEL;
}
double ua = ua_numr / denr;
double ub = ub_numr / denr;
//if (ua >= 0.0 && ua <= 1.0 && ub >= 0.0 && ub <= 1.0)
{
point.x = ax1 + ua * (ax2 - ax1);
point.y = ay1 + ua * (ay2 - ay1);
return 0; //XSEC_TRUE;
}
//return 1; //XSEC_FALSE;
}
} }