1 files changed, 18 insertions, 0 deletions
diff --git a/geometry.c b/geometry.c
index 322deee..057fea0 100644
--- a/geometry.c
+++ b/geometry.c
@@ -140,7 +140,10 @@ int lineIntersection(const LINE *la, const LINE *lb, VERTEX *v) {
   double xb2 = lb->v2.x, yb2 = lb->v2.y;
   double temp;
   int switched = 0;
+  VERTEX v2;
+  
   
+  if(v == NULL) v = &v2;
   
   if(xa1 == xa2 && ya1 == ya2) return INTERSECTION_ERROR;
   if(xb1 == xb2 && yb1 == yb2) return INTERSECTION_ERROR;
@@ -227,6 +230,21 @@ int lineRectIntersections(const LINE *line, const RECTANGLE *rect, int edge, VER
   return ret;
 }
 
+gboolean linePolygonIntersection(const LINE *l, const POLYGON *p) {
+  int i;
+  LINE line;
+  
+  for(i = 0; i < p->nVertices; i++) {
+    line.v1 = p->vertices[i];
+    line.v2 = p->vertices[(i+1)%p->nVertices];
+    
+    if(lineIntersection(l, &line, NULL) == INTERSECTION_SEGMENT_SEGMENT)
+      return TRUE;
+  }
+  
+  return FALSE;
+}
+
 void simplifyPolygon(const POLYGON *in, const RECTANGLE *rect, POLYGON *out) {
   int i, j;
   int a;