Hey, I’m currently working on a glTF model viewer and have been able to get most of the parsing and rendering of glTF models quite far. One issue I’m running into is situations where a node has negative scaling along some axis. This ends up causing some inversion and my models get rendered incorrectly.
The glTF spec notes: " Implementation Note: If the determinant of the transform is a negative value, the winding order of the mesh triangle faces should be reversed. This supports negative scales for mirroring geometry."
I’m not sure how to approach this situation. I know I can control the winding order when creating my graphics pipeline, but to have another pipeline for these negative-scale meshes seems wrong and heavy handed. If I simply reverse the winding order of the indices when loading the model, then my actual model data will be stored reversed, but if I change my scale to a positive number during runtime, I’d have to update the indices as well. Any recommendations would be much appreciated!