Stencil Additions

[EriKWDev]

Motivation

We want to use stencil tests to optimize part of our planar reflection rendering

Added Texture Formats

• Depth32FloatStencil8Uint
• Stencil8Uint

API Additions

Added set_stencil_reference(&mut self, reference: u32) to RenderEncoder trait
Both metal, gles and vulkan support setting it for front and back faces individually, but from what I could find metal only supports setting them both at the same time.

I decided to simply set front and back to same value for now. Could be solved by requiring both be specified as a front_reference: u32 and back_reference: u32. Skipped for now

Metal

Noticed that metal wasn't doing anything with the stencil load/clear ops so implemented those while peeking at wpgu-hal implementation

Testing

Tested and inspected in vulkan. Gles compiles on linux. Macos compiles and runs.

[EriKWDev]

The results using stencil test for planar reflection show performance gain, especially on our weaker laptop targets for the game :)

[EriKWDev]

One thing that caught me was that the TextureColor became a little unintuitive when I wanted to clear the depth and stencils to 1.0 and 0.

OpaqueBlack needed a few extra brain cells for me to associate xD But makes sense once you rule out the other options of what it could mean