Particles ocean

A deep-water surface driven by a real inverse FFT. A Phillips spectrum evolves in frequency space, Stockham passes produce a displacement field, and half a million particles ride the waves through an HDR bloom chain.

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index.tsx renderer.ts ocean-graph.ts tuning.ts camera.ts ocean-common.wgsl noise.wgsl initial-spectrum.wgsl spectrum.wgsl ifft-stage.wgsl normal-foam.wgsl particles.wgsl particles-common.wgsl particles-light.wgsl bloom-bright.wgsl bloom-blur.wgsl bloom-composite.wgsl present.wgsl stage-preview.wgsl

struct NoiseUniforms { seed: u32, resolution: u32 };
@group(0) @binding(0) var<uniform> u: NoiseUniforms;
 
// Random-access form of front's mulberry32. `callIndex` is the number of
// preceding PRNG calls, so each texel reproduces the CPU upload without state.
fn mulberryAt(callIndex: u32) -> f32 {
  let state = u.seed + 0x6d2b79f5u * (callIndex + 1u);
  var t = state;
  t = (t ^ (t >> 15u)) * (t | 1u);
  t = t ^ (t + ((t ^ (t >> 7u)) * (t | 61u)));
  return f32(t ^ (t >> 14u)) / 4294967296.0;
}
fn gaussianPair(callIndex: u32) -> vec2f {
  let u1 = max(mulberryAt(callIndex), 1.17549435e-38);
  let u2 = mulberryAt(callIndex + 1u);
  let magnitude = sqrt(-2.0 * log(u1));
  let angle = 6.283185307179586 * u2;
  return magnitude * vec2f(cos(angle), sin(angle));
}
@fragment fn fs_main(@builtin(position) position: vec4f) -> @location(0) vec4f {
  let coord = vec2u(position.xy - vec2f(0.5));
  let base = (coord.y * u.resolution + coord.x) * 4u;
  return vec4f(gaussianPair(base), gaussianPair(base + 2u));
}