Add check for NULL texcoord values.

code/glTF2Importer.cpp

@@ -437,6 +437,12 @@ void glTF2Importer::ImportMeshes(glTF2::Asset& r)
             }
 
             for (size_t tc = 0; tc < attr.texcoord.size() && tc < AI_MAX_NUMBER_OF_TEXTURECOORDS; ++tc) {
+                if (!attr.texcoord[tc]) {
+                    DefaultLogger::get()->warn("NULL texcoord encountered in mesh \"" + mesh.name +
+                        "\" and will be ignored");
+                    continue;
+                }
+
                 if (attr.texcoord[tc]->count != aim->mNumVertices) {
                     DefaultLogger::get()->warn("Texcoord stream size in mesh \"" + mesh.name +
                                                "\" does not match the vertex count");