EVEngine/docs/dev/ported-material-shaders.md

Ported material & post shaders (Unity / Godot style)

A curated set of "mature" game-engine shaders, exposed through the existing stylize module so they share its StyleInstance / StylePass / StyleRecipe runtime and the same Squirrel API as cartoon, ink, xray, etc. No new module, manifest entry, or binding is required.

What was added

Mesh material shaders (reuse graphics/mesh3d_toon.vert; params arrive as push constants; albedo at binding 1):

style	technique	inspiration
rim	fresnel rim light + lambert	Unity built-in Rim Lighting shader
dissolve	noise dissolve with burn edge	Unity Dissolve / URP community shaders
hologram	fresnel + scanlines + glitch	Godot community Hologram shaders
snow	snow accumulation on normals	Godot community Snow / Ice shaders

Post-process shaders (full-screen passes over the scene color):

style	technique	inspiration
vignette	edge darkening	ubiquitous engine vignette
chromatic	radial + per-channel dispersion	Unity Standard Chromatic Aberration
grain	luminance-adaptive film grain	filmic grain / dither techniques

Licensing note

These are original GLSL implementations of widely-used, technique-level effects — not verbatim copies of Unity or Godot shader source. The Unity built-in shaders and many community shaders carry restrictive or mixed licenses, so nothing here was copied wholesale. The underlying math (value-noise / fbm, fresnel, smoothstep blending, film-grain dither) is standard public-domain technique. Godot's engine is MIT-licensed, but the specific ports above were written fresh against EVEngine's push-constant / binding layout.

If a specific commercial look is required, replace the GLSL in src/modules/stylize/shaders/ and recompile via scripts/compile_stylize_shaders.py.

Adding a shader (in 4 steps)

1. Drop a *.frag in src/modules/stylize/shaders/ following the push-constant convention in the header comment (layout(push_constant) uniform Externals { float data[32]; } u;, index = declareFloat order).
2. Append it to FRAGS in scripts/compile_stylize_shaders.py and run it to produce the embedded *_frag_spv.inc.
3. In src/modules/stylize/EffectShaders.cpp add a StyleDefinition, a param table, and branches in the count / at / bind / create dispatchers.
4. Optionally add a test case in test/stylize_effects.cpp.