[Bf-blender-cvs] [813a656] strand_gpu: Fix crashes when generating fibers without any control curves present.

[Lukas Tönne]

Commit: 813a6568aa2a638df13fb4529798764fcc57b28e
Author: Lukas Tönne
Date:   Wed Jul 13 18:38:35 2016 +0200
Branches: strand_gpu
https://developer.blender.org/rB813a6568aa2a638df13fb4529798764fcc57b28e

Fix crashes when generating fibers without any control curves present.

===================================================================

M	source/blender/blenkernel/intern/strands.c
M	source/blender/gpu/intern/gpu_buffers.c

===================================================================

diff --git a/source/blender/blenkernel/intern/strands.c b/source/blender/blenkernel/intern/strands.c
index 543f0d9..9a8c603 100644
--- a/source/blender/blenkernel/intern/strands.c
+++ b/source/blender/blenkernel/intern/strands.c
@@ -488,6 +488,9 @@ static void strand_calc_root_distance(StrandFiber *fiber, const float loc[3], co
 
 static void strands_calc_weights(const Strands *strands, struct DerivedMesh *scalp, StrandFiber *fibers, int num_fibers)
 {
+	if (strands->totcurves == 0)
+		return;
+	
 	float (*strandloc)[3] = MEM_mallocN(sizeof(float) * 3 * strands->totcurves, "strand locations");
 	KDTree *tree = BLI_kdtree_new(strands->totcurves);
 	
diff --git a/source/blender/gpu/intern/gpu_buffers.c b/source/blender/gpu/intern/gpu_buffers.c
index 5f52e55..279fcd1 100644
--- a/source/blender/gpu/intern/gpu_buffers.c
+++ b/source/blender/gpu/intern/gpu_buffers.c
@@ -2421,7 +2421,7 @@ static int strands_fiber_length(StrandFiber *fiber, StrandCurve *curves, unsigne
 		fnumverts += fiber->control_weight[k] * (float)curves[index].num_verts;
 	}
 	UNUSED_VARS(totcurves);
-	int orig_num_verts = (int)ceil(fnumverts);
+	int orig_num_verts = max_ii((int)ceil(fnumverts), 2);
 	return BKE_strand_curve_cache_size(orig_num_verts, subdiv);
 }
 
@@ -2454,7 +2454,7 @@ static int editstrands_fiber_length(StrandFiber *fiber, BMStrandCurve *curves, i
 		fnumverts += fiber->control_weight[k] * (float)curves[index].num_verts;
 	}
 	UNUSED_VARS(totcurves);
-	int orig_num_verts = (int)ceil(fnumverts);
+	int orig_num_verts = max_ii((int)ceil(fnumverts), 2);
 	return BKE_strand_curve_cache_size(orig_num_verts, subdiv);
 }