Added support for texture cubemaps and IBL using reflection probes

[adriengivry]

Description

• Added texture cube support
• Added reflection render pass (generates a cubemap for each reflection probe)
• Added reflection render feature (sends the cubemap to an entity about to be drawn.
• Reworked scene parsing:
  • Side effect: cannot cull per-model anymore, can only cull per-mesh
• Added Mat3 uniform support
• Added visibility flags to the material renderer, to exlude an actor from certain passes
• Deprecated cull model, cull mesh is preferred for now (will be added back when tackling Investigate implementing a proper frame builder #564)
• Added "depth test" option to debug shape drawer, so that bounds/volumes can be shown through objects
• Reflection probe data is passed to the shader as a UBO. In the future, we should implement a proper solution to handle multiple UBOs, and track their binding index
• Added material settings to enable/disable reflection capture & usage on a particular material.
• Separated material editor settings into pipeline (state mask) & general settings.
• Vastly improved PBR shader (re-organized)

Limitations

• One mesh can only be affected by one reflection probe, so splitting the mesh might be necessary to achieve some desired effect. A follow up task would be to introduce probe blending.
• No support for offline baking, but cubemaps can be generated when the scene is loaded, so that's a good enough solution for most cases.
• Cubemaps cannot be viewed in the texture debugger (no ImGui widget to do that afaik)

Related Issue(s)

Fixes #521
Fixes #520
Fixes #566

To-Do

• Address bug with infinite reflections (burn in), happening when a reflective objects reflect each other
• Add probe influence volume setting to area
• Add option for a probe to be realtime or on enable (once)
• Expose probe resolution setting in the editor
• Evaluate implementing box projection to correct reflections indoors
• Add options to select which drawable should be part of the reflection render pass (e.g. static/dynamic visibility flags)
• Add option to make the influence volume infinite
• Ensure asset view has its own reflections
• Fix probe debug volume has depth test
• Make it work properly with more than 1 probe
• Cleanup shader code
• Make sure to clear cubemap before draw
• Clean-up ReflectionRenderFeature::OnBeforeDraw
• Add material settings to toggle reflection capture and impact (also unify with default material shadow settings)
• Fix frustum culling with custom bounding spheres broken (e.g. vase particles in Sponza)
• Differ cubemap regeneration over multiple frames (6? one per face)
• Add lua bindings (don't forget culling FrustumBehaviour)
• Investigate Engine UBO becoming invalid: not related to this PR, but this PR makes the repro rate way higher (OpenGL crashes after allocating as many render buffers as the first UBO index #566)
• Fix texture cube crashes the texture debugger
• Double check that the magenta material (fallback) works
• Clean-up implementation
• Find workaround to renderbuffer problem (OpenGL crashes after allocating as many render buffers as the first UBO index #566) doesn't have to be a complete solution found a proper solution!
• Fix influence offset weird results
• Sometimes partial cubemaps are presented expected with double buffering, same issue in Unity
• Investigate black pixels
• Add coefficient/multiplier setting to probe

Screenshots/GIFs

New default scene

OvEditor_JIPhg5508u.mp4

OvEditor_yLvegU9RnW.mp4

OvEditor_NaLtmsvj4J.mp4

OvEditor_HWR5t5k0JL.mp4