Implement LUT3DEffect

[vanruesc]

Description

Implement a LUT3DEffect based on the implementation in v6.

References:

• https://affinityspotlight.com/article/1d-vs-3d-luts/

Tasks

• Create LUT3DEffect.
• Create lut demo.
• Add unit test.

Implementation Details

• The implementation requires minimal adjustments.
• WebGL 2 is now required which means that 3D textures can be assumed to be available.
  • Support for 2D LUTs should be removed.
  • LookupTexture must be updated accordingly.