From da12f242c6d8da930aa3c2e90fd21a637cd1f195 Mon Sep 17 00:00:00 2001
From: yum <yum.food.vr@gmail.com>
Date: Mon, 20 Jul 2026 16:35:51 -0700
Subject: Add glitter normal map override option

---
 math.cginc | 8 ++++++++
 1 file changed, 8 insertions(+)

(limited to 'math.cginc')

diff --git a/math.cginc b/math.cginc
index 0692440..270ca15 100755
--- a/math.cginc
+++ b/math.cginc
@@ -334,4 +334,12 @@ float3 srgb_to_linear(float3 srgb_color) {
   return lerp(lo, hi, step(0.04045f, srgb_color));
 }
 
+float3x3 tbn_from_normal_tangent(float3 normal, float4 tangent) {
+  float3 n = normal;
+  float3 t = tangent.xyz;
+  t = normalize(t - n * dot(n, t));  // Gram-Schmidt to avoid skew
+  float3 b = normalize(cross(n, t)) * tangent.w;
+  return float3x3(t, b, n);
+}
+
 #endif  // __MATH_INC
-- 
cgit v1.2.3