[Bf-blender-cvs] SVN commit: /data/svn/bf-blender [58167] trunk/blender/source/blender/bmesh /operators/bmo_bridge.c: fix for bridge tool where the 2 loops overlap ( typical use for scanfill), however its nice to support with bridge too since it can do subdivisions, handles customdata and fills in quads.

[Campbell Barton]

Revision: 58167
          http://projects.blender.org/scm/viewvc.php?view=rev&root=bf-blender&revision=58167
Author:   campbellbarton
Date:     2013-07-11 08:37:30 +0000 (Thu, 11 Jul 2013)
Log Message:
-----------
fix for bridge tool where the 2 loops overlap (typical use for scanfill), however its nice to support with bridge too since it can do subdivisions, handles customdata and fills in quads.

Modified Paths:
--------------
    trunk/blender/source/blender/bmesh/operators/bmo_bridge.c

Modified: trunk/blender/source/blender/bmesh/operators/bmo_bridge.c
===================================================================
--- trunk/blender/source/blender/bmesh/operators/bmo_bridge.c	2013-07-11 08:25:37 UTC (rev 58166)
+++ trunk/blender/source/blender/bmesh/operators/bmo_bridge.c	2013-07-11 08:37:30 UTC (rev 58167)
@@ -144,11 +144,13 @@
                              struct BMEdgeLoopStore *el_store_b,
                              const bool use_merge, const float merge_factor)
 {
+	const float eps = 0.00001f;
 	LinkData *el_a_first, *el_b_first;
 	const bool is_closed = BM_edgeloop_is_closed(el_store_a) && BM_edgeloop_is_closed(el_store_b);
 	int el_store_a_len, el_store_b_len;
 	bool el_store_b_free = false;
 	float el_dir[3];
+	float dot_a, dot_b;
 	const bool use_edgeout = true;
 
 	el_store_a_len = BM_edgeloop_length_get((struct BMEdgeLoopStore *)el_store_a);
@@ -202,9 +204,22 @@
 		BM_edgeloop_calc_normal_aligned(bm, el_store_b, no);
 	}
 
-	if ((dot_v3v3(BM_edgeloop_normal_get(el_store_a), el_dir) < 0.0f) !=
-		(dot_v3v3(BM_edgeloop_normal_get(el_store_b), el_dir) < 0.0f))
+	dot_a = dot_v3v3(BM_edgeloop_normal_get(el_store_a), el_dir);
+	dot_b = dot_v3v3(BM_edgeloop_normal_get(el_store_b), el_dir);
+
+	if (UNLIKELY((len_squared_v3(el_dir) < eps) ||
+	             ((fabsf(dot_a) < eps) && (fabsf(dot_b) < eps))))
 	{
+		/* in this case there is no depth between the two loops,
+		 * eg: 2x 2d circles, one scaled smaller,
+		 * in this case 'el_dir' cant be used, just ensure we have matching flipping. */
+		if (dot_v3v3(BM_edgeloop_normal_get(el_store_a),
+		             BM_edgeloop_normal_get(el_store_b)) < 0.0f)
+		{
+			BM_edgeloop_flip(bm, el_store_b);
+		}
+	}
+	else if ((dot_a < 0.0f) != (dot_a < 0.0f)) {
 		BM_edgeloop_flip(bm, el_store_b);
 	}