Add cloth lobe & IBL DFG LUTs

- add monte carlo integrator to produce the luts
- fix layer energy integration; should be multiplicative, not additive

1 files changed, 1 insertions, 0 deletions

diff --git a/math.cginc b/math.cginc
index 0d59121..af71fc6 100644
--- a/math.cginc
+++ b/math.cginc
@@ -3,6 +3,7 @@
 
 #define PI 3.14159265358979f
 #define RCP_PI (1.0f / PI)
+#define TAU (2.0f * PI)
 
 float sin_noise_3d(float3 uvw) {
   return sin(uvw[0]) * sin(uvw[1]) * sin(uvw[2]);