tree 45d4a59cf1d9a3838a9506f86f265c8bf9d6607b
parent 9e3dca1e5848f2826473467a4e1242c263f3a7fa
author Nicolas Capens <capn@google.com> 1631334657 -0400
committer Nicolas Capens <nicolascapens@google.com> 1631798286 +0000

Clamp depth before the depth test

Previously we clamped fragment depth right after interpolation, and
after shader execution for shader-provided depth. This means logically
it could be clamped twice, although only one of them would actually be
used. It was also confusing to understand where it was subsequently
consumed, and didn't closely follow the Vulkan spec which considers
depth clamp a part of the depth test (but, importantly, takes place
regardless of the value of depthTestEnable).

This change performs depth clamping right before the actual depth test.

Bug: b/185227903
Change-Id: I4307b9beef2e1a10606bf9accac5c6b86daa6d67
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/57008
Kokoro-Result: kokoro <noreply+kokoro@google.com>
Tested-by: Nicolas Capens <nicolascapens@google.com>
Reviewed-by: Sean Risser <srisser@google.com>