General particle bug fixes + few small goodies

The goodies:
* Curves can be used as normal dynamic effectors too with 
  the new "curve" field shape.
* Group visualization has optional duplication counts for
  each object in the specified group.
* Object & group visualizations, which are done without
  taking the dupliobject's global position into account
  (unless the whole group is used). This is much nicer than
  the previous behavior, but I added a "Use Global Location"
  option for those who want to use it the old way.
* The active particle system's particles are now drawn a 
  with theme coloured outline instead of pure white.
* Added object aligned velocity factors (buttons categorized
  and re-organized too).

Bug fixes:
* Absorption didn't work as the ui toggle button was forgotten.
* Some other force field ui tweaks.
* Crash after adding children and changing trails count.
* Display types "cross" and "axis" crashed.
* Particles weren't drawn with correct coloring.
* Billboards didn't update properly in viewport to camera
  location changes.
* Particle rotation wasn't recreated correctly from point cache.
* Changing particles amount crashed sometimes.
* Some files with child hair crashed on loading.
* Compiler warning fixes.
* Adding boids crashed on frame 1;

1 files changed, 88 insertions, 0 deletions

diff --git a/source/blender/blenkernel/intern/bvhutils.c b/source/blender/blenkernel/intern/bvhutils.c
index d9e005811d0..f2526231d50 100644
--- a/source/blender/blenkernel/intern/bvhutils.c
+++ b/source/blender/blenkernel/intern/bvhutils.c
@@ -479,6 +479,32 @@ static void mesh_faces_spherecast(void *userdata, int index, const BVHTreeRay *r
 	} while(t2);
 }
 
+// Callback to bvh tree nearest point. The tree must bust have been built using bvhtree_from_mesh_edges.
+// userdata must be a BVHMeshCallbackUserdata built from the same mesh as the tree.
+static void mesh_edges_nearest_point(void *userdata, int index, const float *co, BVHTreeNearest *nearest)
+{
+	const BVHTreeFromMesh *data = (BVHTreeFromMesh*) userdata;
+	MVert *vert	= data->vert;
+	MEdge *edge = data->edge + index;
+	float nearest_tmp[3], dist;
+
+	float *t0, *t1;
+	t0 = vert[ edge->v1 ].co;
+	t1 = vert[ edge->v2 ].co;
+	
+	PclosestVL3Dfl(nearest_tmp, co, t0, t1);
+	dist = VecLenf(nearest_tmp, co);
+	
+	if(dist < nearest->dist)
+	{
+		nearest->index = index;
+		nearest->dist = dist;
+		VECCOPY(nearest->co, nearest_tmp);
+		VecSubf(nearest->no, t0, t1);
+		Normalize(nearest->no);
+	}
+}
+
 /*
  * BVH builders
  */
@@ -605,6 +631,68 @@ BVHTree* bvhtree_from_mesh_faces(BVHTreeFromMesh *data, DerivedMesh *mesh, float
 
 }
 
+// Builds a bvh tree.. where nodes are the faces of the given mesh.
+BVHTree* bvhtree_from_mesh_edges(BVHTreeFromMesh *data, DerivedMesh *mesh, float epsilon, int tree_type, int axis)
+{
+	BVHTree *tree = bvhcache_find(&mesh->bvhCache, BVHTREE_FROM_EDGES);
+
+	//Not in cache
+	if(tree == NULL)
+	{
+		int i;
+		int numEdges= mesh->getNumEdges(mesh);
+		MVert *vert	= mesh->getVertDataArray(mesh, CD_MVERT);
+		MEdge *edge = mesh->getEdgeDataArray(mesh, CD_MEDGE);
+
+		if(vert != NULL && edge != NULL)
+		{
+			/* Create a bvh-tree of the given target */
+			tree = BLI_bvhtree_new(numEdges, epsilon, tree_type, axis);
+			if(tree != NULL)
+			{
+				for(i = 0; i < numEdges; i++)
+				{
+					float co[4][3];
+					VECCOPY(co[0], vert[ edge[i].v1 ].co);
+					VECCOPY(co[1], vert[ edge[i].v2 ].co);
+			
+					BLI_bvhtree_insert(tree, i, co[0], 2);
+				}
+				BLI_bvhtree_balance(tree);
+
+				//Save on cache for later use
+//				printf("BVHTree built and saved on cache\n");
+				bvhcache_insert(&mesh->bvhCache, tree, BVHTREE_FROM_EDGES);
+			}
+		}
+	}
+	else
+	{
+//		printf("BVHTree is already build, using cached tree\n");
+	}
+
+
+	//Setup BVHTreeFromMesh
+	memset(data, 0, sizeof(*data));
+	data->tree = tree;
+
+	if(data->tree)
+	{
+		data->cached = TRUE;
+
+		data->nearest_callback = mesh_edges_nearest_point;
+		data->raycast_callback = NULL;
+
+		data->mesh = mesh;
+		data->vert = mesh->getVertDataArray(mesh, CD_MVERT);
+		data->edge = mesh->getEdgeDataArray(mesh, CD_MEDGE);
+
+		data->sphere_radius = epsilon;
+	}
+	return data->tree;
+
+}
+
 // Frees data allocated by a call to bvhtree_from_mesh_*.
 void free_bvhtree_from_mesh(struct BVHTreeFromMesh *data)
 {