[Bf-blender-cvs] SVN commit: /data/svn/bf-blender [54855] trunk/blender/source/blender/ blenkernel/intern/rigidbody.c: rigidbody: Don' t embed collision margin if object has no volume

[Sergej Reich]

Revision: 54855
          http://projects.blender.org/scm/viewvc.php?view=rev&root=bf-blender&revision=54855
Author:   sergof
Date:     2013-02-25 15:51:53 +0000 (Mon, 25 Feb 2013)
Log Message:
-----------
rigidbody: Don't embed collision margin if object has no volume

While it's not a good idea to create convex hull shapes from objects
with no volume, this makes them behave a little nicer.

Fixes [#34410] Planes with Rigid Body always keep distance to colliding objects

Modified Paths:
--------------
    trunk/blender/source/blender/blenkernel/intern/rigidbody.c

Modified: trunk/blender/source/blender/blenkernel/intern/rigidbody.c
===================================================================
--- trunk/blender/source/blender/blenkernel/intern/rigidbody.c	2013-02-25 13:15:42 UTC (rev 54854)
+++ trunk/blender/source/blender/blenkernel/intern/rigidbody.c	2013-02-25 15:51:53 UTC (rev 54855)
@@ -347,6 +347,7 @@
 	float capsule_height;
 	float hull_margin = 0.0f;
 	bool can_embed = true;
+	bool has_volume;
 
 	/* sanity check */
 	if (rbo == NULL)
@@ -404,11 +405,13 @@
 
 		case RB_SHAPE_CONVEXH:
 			/* try to emged collision margin */
-			if (!(rbo->flag & RBO_FLAG_USE_MARGIN))
+			has_volume = (MIN3(size[0], size[1], size[2]) > 0.0f);
+
+			if (!(rbo->flag & RBO_FLAG_USE_MARGIN) && has_volume)
 				hull_margin = 0.04f;
 			new_shape = rigidbody_get_shape_convexhull_from_mesh(ob, hull_margin, &can_embed);
 			if (!(rbo->flag & RBO_FLAG_USE_MARGIN))
-				rbo->margin = (can_embed) ? 0.04f : 0.0f;  /* RB_TODO ideally we shouldn't directly change the margin here */
+				rbo->margin = (can_embed && has_volume) ? 0.04f : 0.0f;  /* RB_TODO ideally we shouldn't directly change the margin here */
 			break;
 		case RB_SHAPE_TRIMESH:
 			new_shape = rigidbody_get_shape_trimesh_from_mesh(ob);