Provide ray hit/nearest information on which side of the quad the ray hit.

Patch by MiikaH.

2 files changed, 11 insertions, 0 deletions

diff --git a/source/blender/blenkernel/intern/bvhutils.c b/source/blender/blenkernel/intern/bvhutils.c
index 24583c124e6..752bdab2c00 100644
--- a/source/blender/blenkernel/intern/bvhutils.c
+++ b/source/blender/blenkernel/intern/bvhutils.c
@@ -383,6 +383,9 @@ static void mesh_faces_nearest_point(void *userdata, int index, const float co[3
 			nearest->dist = dist;
 			copy_v3_v3(nearest->co, nearest_tmp);
 			normal_tri_v3(nearest->no, t0, t1, t2);
+
+			if (t1 == vert[face->v3].co)
+				nearest->flags |= BVH_ONQUAD;
 		}
 
 		t1 = t2;
@@ -420,6 +423,9 @@ static void mesh_faces_spherecast(void *userdata, int index, const BVHTreeRay *r
 			madd_v3_v3v3fl(hit->co, ray->origin, ray->direction, dist);
 
 			normal_tri_v3(hit->no, t0, t1, t2);
+
+			if (t1 == vert[face->v3].co)
+				hit->flags |= BVH_ONQUAD;
 		}
 
 		t1 = t2;
diff --git a/source/blender/blenlib/BLI_kdopbvh.h b/source/blender/blenlib/BLI_kdopbvh.h
index 7041c122ff9..5ec8247c03a 100644
--- a/source/blender/blenlib/BLI_kdopbvh.h
+++ b/source/blender/blenlib/BLI_kdopbvh.h
@@ -49,11 +49,15 @@ typedef struct BVHTreeOverlap {
 	int indexB;
 } BVHTreeOverlap;
 
+/* flags */
+#define BVH_ONQUAD (1<<0)
+
 typedef struct BVHTreeNearest {
 	int index;          /* the index of the nearest found (untouched if none is found within a dist radius from the given coordinates) */
 	float co[3];        /* nearest coordinates (untouched it none is found within a dist radius from the given coordinates) */
 	float no[3];        /* normal at nearest coordinates (untouched it none is found within a dist radius from the given coordinates) */
 	float dist;         /* squared distance to search arround */
+	int flags;
 } BVHTreeNearest;
 
 typedef struct BVHTreeRay {
@@ -67,6 +71,7 @@ typedef struct BVHTreeRayHit {
 	float co[3];        /* coordinates of the hit point */
 	float no[3];        /* normal on hit point */
 	float dist;         /* distance to the hit point */
+	int flags;
 } BVHTreeRayHit;
 
 /* callback must update nearest in case it finds a nearest result */