From a9217eb6c67282ac2451f1eafcedca04a8c5e564 Mon Sep 17 00:00:00 2001
From: yum <yum.food.vr@gmail.com>
Date: Sun, 29 Mar 2026 15:44:01 -0700
Subject: Continue work on glitter

---
 glitter.slang | 74 -----------------------------------------------------------
 1 file changed, 74 deletions(-)
 delete mode 100644 glitter.slang

(limited to 'glitter.slang')

diff --git a/glitter.slang b/glitter.slang
deleted file mode 100644
index 5442a0f..0000000
--- a/glitter.slang
+++ /dev/null
@@ -1,74 +0,0 @@
-#ifndef __GLITTER_INC
-#define __GLITTER_INC
-
-#define PI 3.1415926535897932384626433832795028841971
-
-float gaussian(float3 x, float3 mu, float sigma) {
-  float3 x_minus_mu = x - mu;
-  return exp(-dot(x_minus_mu, x_minus_mu) / (2 * sigma * sigma)) / (sigma * sqrt(2 * PI));
-}
-
-float det(float2x2 m) {
-  return m[0][0] * m[1][1] - m[0][1] * m[1][0];
-}
-
-float dirac(float3 x) {
-  // Ternary operator short-circuits in slang >:(
-  return any(abs(x) < 1e-4) ? 1e4 : 0;
-}
-
-// Maps a point on the unit hemisphere to an inscribed circle.
-float2 hemisphere_to_inscribed_circle(float3 p) {
-  // TODO
-  return 0;
-}
-
-float3 rand3_hash(float3 p)
-{
-    // Improved Murmurhash3 by Squirrel Eiserloh (GDC 2017)
-    p = float3(dot(p, float3(127.1, 311.7, 74.7)),
-               dot(p, float3(269.5, 183.3, 246.1)),
-               dot(p, float3(113.5, 271.9, 124.6)));
-    return -1.0 + 2.0 * frac(sin(p) * 43758.5453123);
-}
-
-public float D_Kemppinen(
-  float3 worldPos,
-  float3 H_tan,  // halfway vector in tangent space
-  float amount,
-  float roughness)
-{
-  float2x2 J_T__omega_h = 0;  // TODO
-  float det_J_T__omega_h = det(J_T__omega_h);
-  
-  float sum = 0;
-  // x is the current world space position.
-  float3 x = worldPos;
-  // omega_h is the halfway vector *in TBN coordinates.*
-  float3 omega_h = H_tan;
-  float3 T_omega_h = float3(
-      hemisphere_to_inscribed_circle(omega_h),
-      0);
-  uint K_p = 1;  // TODO
-  for (uint i = 0; i < K_p; ++i) {
-    // x_i is the position of the facet.
-    float3 x_i = worldPos;  // TODO randomize position
-    // mu_i is the orientation of the facet.
-    float3 mu_i = abs(rand3_hash(x_i));
-
-    float a_star = roughness;
-
-    float cur_gauss = gaussian(
-        T_omega_h,
-        mu_i,
-        a_star * sqrt(det_J_T__omega_h));
-
-    sum += cur_gauss * dirac(x_i - x);
-  }
-
-  float scale = det_J_T__omega_h / K_p;
-  return sum * scale;
-}
-
-#endif  // __GLITTER_INC
-
-- 
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