Kelsidavis-WoWee/assets/shaders/shadow.vert.glsl
Kelsi ef1e5abe8e Add shader-driven tree beautification: wind sway, SSS, color variation, AO
- Vertex wind animation: 3-layer displacement (trunk/branch/leaf) with
  quadratic height scaling so bases stay grounded
- Shadow pass: matching vertex displacement split into foliage/non-foliage
  passes, removed UV-wiggle approach
- Leaf subsurface scattering: warm backlit glow when looking toward sun
- Per-instance color variation: hue/brightness from position hash via flat
  varying to avoid interpolation flicker
- Canopy ambient occlusion: height-based darkening of tree interiors
- Detail normal perturbation: UV-only procedural normals to break flat cards
- Bayer 4x4 ordered dither replacing sin-hash noise for alpha edges
- Foliage skips shadow map sampling and specular to prevent flicker from
  swaying geometry sampling unstable shadow/highlight values
2026-02-23 03:53:50 -08:00

57 lines
1.8 KiB
GLSL

#version 450
layout(push_constant) uniform Push {
mat4 lightSpaceMatrix;
mat4 model;
} push;
layout(set = 0, binding = 1) uniform ShadowParams {
int useBones;
int useTexture;
int alphaTest;
int foliageSway;
float windTime;
float foliageMotionDamp;
};
layout(location = 0) in vec3 aPos;
layout(location = 1) in vec2 aTexCoord;
layout(location = 2) in vec4 aBoneWeights;
layout(location = 3) in vec4 aBoneIndicesF;
layout(location = 0) out vec2 TexCoord;
layout(location = 1) out vec3 WorldPos;
void main() {
vec4 pos = vec4(aPos, 1.0);
// Wind vertex displacement for foliage (matches m2.vert.glsl)
if (foliageSway != 0) {
vec3 worldRef = push.model[3].xyz;
float heightFactor = clamp(pos.z / 20.0, 0.0, 1.0);
heightFactor *= heightFactor;
// Layer 1: Trunk sway
float trunkPhase = windTime * 0.8 + dot(worldRef.xy, vec2(0.1, 0.13));
float trunkSwayX = sin(trunkPhase) * 0.35 * heightFactor;
float trunkSwayY = cos(trunkPhase * 0.7) * 0.25 * heightFactor;
// Layer 2: Branch sway
float branchPhase = windTime * 1.7 + dot(worldRef.xy, vec2(0.37, 0.71));
float branchSwayX = sin(branchPhase + pos.y * 0.4) * 0.15 * heightFactor;
float branchSwayY = cos(branchPhase * 1.1 + pos.x * 0.3) * 0.12 * heightFactor;
// Layer 3: Leaf flutter
float leafPhase = windTime * 4.5 + dot(aPos, vec3(1.7, 2.3, 0.9));
float leafFlutterX = sin(leafPhase) * 0.06 * heightFactor;
float leafFlutterY = cos(leafPhase * 1.3) * 0.05 * heightFactor;
pos.x += trunkSwayX + branchSwayX + leafFlutterX;
pos.y += trunkSwayY + branchSwayY + leafFlutterY;
}
vec4 worldPos = push.model * pos;
WorldPos = worldPos.xyz;
TexCoord = aTexCoord;
gl_Position = push.lightSpaceMatrix * worldPos;
}