Problem with rendering matcaps after perspective fix

During Matcaps call for content @Quijx reported unwanted behavior with rendering matcaps and @fclem fixed it.

New behavior works great for sculpting but unfortunately it completely broke shading for hard surface models. Because of perspective fix flat surfaces are no longer rendered as flat surfaces.

Cube on right is shaded flat. On left object selected faces have flat vertex normals. With this matcap those faces should be rendered with single color as they are completely flat.

Can we make this perspective fix optional and disabled by default? Proper rendering of vertex normals is crucial for modeling.


I believe that the current mapping is actually just fine. Any flat surface in real life will reflect different parts of its environment, and if you must have uniform shading on co-planar surfaces you can simply switch to orthographic view.

However, if you view a larger flat surface, depending on which debugging matcap you use, the surface may appear convex or concave to a varied extent. Although it’s a small issue, any further adjustments could break reflection checkers in more crucial situations such as this one.



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