SL-366 - more cases where skinned weights can go awry, and a bunch more asserts to verify.

2 files changed, 12 insertions, 2 deletions

diff --git a/indra/newview/llfloatermodelpreview.cpp b/indra/newview/llfloatermodelpreview.cpp
index ceb3566d95..cda704f47b 100755
--- a/indra/newview/llfloatermodelpreview.cpp
+++ b/indra/newview/llfloatermodelpreview.cpp
@@ -3317,14 +3317,17 @@ void LLModelPreview::genBuffers(S32 lod, bool include_skin_weights)
 					LLVector3 pos(vf.mPositions[i].getF32ptr());
 
 					const LLModel::weight_list& weight_list = base_mdl->getJointInfluences(pos);
+                    llassert(weight_list.size()>0 && weight_list.size() <= 4); // LLModel::loadModel() should guarantee this
 
 					LLVector4 w(0,0,0,0);
 					
 					for (U32 i = 0; i < weight_list.size(); ++i)
 					{
-						F32 wght = llmin(weight_list[i].mWeight, 0.999999f);
+						F32 wght = llclamp(weight_list[i].mWeight, 0.001f, 0.999f);
 						F32 joint = (F32) weight_list[i].mJointIdx;
 						w.mV[i] = joint + wght;
+                        llassert(w.mV[i]-(S32)w.mV[i]>0.0f); // because weights are non-zero, and range of wt values
+                                                             //should not cause floating point precision issues.
 					}
 
 					*(weights_strider++) = w;
diff --git a/indra/newview/llskinningutil.cpp b/indra/newview/llskinningutil.cpp
index fbe45c8ea6..732afdfa9a 100644
--- a/indra/newview/llskinningutil.cpp
+++ b/indra/newview/llskinningutil.cpp
@@ -291,12 +291,15 @@ void LLSkinningUtil::checkSkinWeights(LLVector4a* weights, U32 num_vertices, con
         {
             F32 *w = weights[j].getF32ptr();
             
+            F32 wsum = 0.0;
             for (U32 k=0; k<4; ++k)
             {
                 S32 i = llfloor(w[k]);
                 llassert(i>=0);
                 llassert(i<max_joints);
+                wsum += w[k]-i;
             }
+            llassert(wsum > 0.0f);
         }
     }
 #endif
@@ -310,7 +313,7 @@ void LLSkinningUtil::getPerVertexSkinMatrix(
     LLMatrix4a& final_mat,
     U32 max_joints)
 {
-
+    bool valid_weights = true;
     final_mat.clear();
 
     S32 idx[4];
@@ -336,6 +339,7 @@ void LLSkinningUtil::getPerVertexSkinMatrix(
     if (handle_bad_scale && scale <= 0.f)
     {
         wght = LLVector4(1.0f, 0.0f, 0.0f, 0.0f);
+        valid_weights = false;
     }
     else
     {
@@ -353,5 +357,8 @@ void LLSkinningUtil::getPerVertexSkinMatrix(
 
         final_mat.add(src);
     }
+    // SL-366 - with weight validation/cleanup code, it should no longer be
+    // possible to hit the bad scale case.
+    llassert(valid_weights);
 }