Discussion started in #4878

Early-Z discards are an optimization that is disabled when fragment shaders have side effects such as writing to a storage binding. There are occasions where it's desirable to have both early-z discards and still write to storage, though, such as an algorithm that builds visibility buffers.

Native APIs have shader attributes that can be set for the fragment entry point to force this behavior.

• MSL: [[early_fragment_tests]] (Section 5.1.2)
• SPIR-V: EarlyFragmentTests execution mode
• GLSL: layout(early_fragment_tests)
• HLSL: earlydepthstencil

While not an Milestone 0 priority, we should evaluate this functionality for future iterations of the spec.