Fix:core:Fix signed int overflow in polygon clipping, to fix rendering errors in high zoom levels.|May be related to #1062.

git-svn-id: http://svn.code.sf.net/p/navit/code/trunk/navit@5418 ffa7fe5e-494d-0410-b361-a75ebd5db220

1 files changed, 4 insertions, 4 deletions

diff --git a/navit/graphics.c b/navit/graphics.c
index 1cf0ac89..f8057c73 100644
--- a/navit/graphics.c
+++ b/navit/graphics.c
@@ -1689,19 +1689,19 @@ poly_intersection(struct point *p1, struct point *p2, struct point_rect *r, int
 	int dy=p2->y-p1->y;
 	switch(edge) {
 	case 0:
-		ret->y=p1->y+(r->lu.x-p1->x)*dy/dx;
+		ret->y=p1->y+((float)r->lu.x-p1->x)*dy/dx;
 		ret->x=r->lu.x;
 		break;
 	case 1:
-		ret->y=p1->y+(r->rl.x-p1->x)*dy/dx;
+		ret->y=p1->y+((float)r->rl.x-p1->x)*dy/dx;
 		ret->x=r->rl.x;
 		break;
 	case 2:
-		ret->x=p1->x+(r->lu.y-p1->y)*dx/dy;
+		ret->x=p1->x+((float)r->lu.y-p1->y)*dx/dy;
 		ret->y=r->lu.y;
 		break;
 	case 3:
-		ret->x=p1->x+(r->rl.y-p1->y)*dx/dy;
+		ret->x=p1->x+((float)r->rl.y-p1->y)*dx/dy;
 		ret->y=r->rl.y;
 		break;
 	}