Merge pull request #1827 from JeffH-BMG/patch-1

Fix import of binary STL files in double-precision builds

code/STLLoader.cpp

@@ -449,26 +449,43 @@ bool STLImporter::LoadBinaryFile()
     aiVector3D *vp = pMesh->mVertices = new aiVector3D[pMesh->mNumVertices];
     aiVector3D *vn = pMesh->mNormals = new aiVector3D[pMesh->mNumVertices];
 
+    typedef aiVector3t<float> aiVector3F;
+    aiVector3F* theVec;
+    aiVector3F theVec3F;
+    
     for ( unsigned int i = 0; i < pMesh->mNumFaces; ++i ) {
         // NOTE: Blender sometimes writes empty normals ... this is not
         // our fault ... the RemoveInvalidData helper step should fix that
-        ::memcpy( vn, sz, sizeof( aiVector3D ) );
-        sz += sizeof(aiVector3D);
+
+        // There's one normal for the face in the STL; use it three times
+        // for vertex normals
+        theVec = (aiVector3F*) sz;
+        ::memcpy( &theVec3F, theVec, sizeof(aiVector3F) );
+        vn->x = theVec3F.x; vn->y = theVec3F.y; vn->z = theVec3F.z;
         *(vn+1) = *vn;
         *(vn+2) = *vn;
+        ++theVec;
         vn += 3;
 
-        ::memcpy( vp, sz, sizeof( aiVector3D ) );
+        // vertex 1
+        ::memcpy( &theVec3F, theVec, sizeof(aiVector3F) );
+        vp->x = theVec3F.x; vp->y = theVec3F.y; vp->z = theVec3F.z;
+        ++theVec;
         ++vp;
-        sz += sizeof(aiVector3D);
 
-        ::memcpy( vp, sz, sizeof( aiVector3D ) );
+        // vertex 2
+        ::memcpy( &theVec3F, theVec, sizeof(aiVector3F) );
+        vp->x = theVec3F.x; vp->y = theVec3F.y; vp->z = theVec3F.z;
+        ++theVec;
         ++vp;
-        sz += sizeof(aiVector3D);
 
-        ::memcpy( vp, sz, sizeof( aiVector3D ) );
+        // vertex 3
+        ::memcpy( &theVec3F, theVec, sizeof(aiVector3F) );
+        vp->x = theVec3F.x; vp->y = theVec3F.y; vp->z = theVec3F.z;
+        ++theVec;
         ++vp;
-        sz += sizeof(aiVector3D);
+        
+        sz = (const unsigned char*) theVec;
 
         uint16_t color = *((uint16_t*)sz);
         sz += 2;