fix ssao

1 files changed, 19 insertions, 0 deletions

diff --git a/math.cginc b/math.cginc
index 8ada893..bb01823 100644
--- a/math.cginc
+++ b/math.cginc
@@ -283,4 +283,23 @@ float3 cmykToRgb(float4 cmyk) {
     (1 - cmyk[2]) * (1 - cmyk[3]));

 }

 

+// Cartesian to cube hexagonal coordinates.

+// Based on this: https://backdrifting.net/post/064_hex_grids

+#define TWO_OVER_THREE  0.6666666666666666f

+#define SQRT_3_OVER_2   0.8660254037844386f

+

+float3 cart_to_hex(float2 cart) {

+  float p = cart.x;

+  float q = dot(cart, float2(0.5f, SQRT_3_OVER_2));

+  float r = dot(cart, float2(0.5f, -SQRT_3_OVER_2));

+

+  return float3(p, q, r) * TWO_OVER_THREE;

+}

+

+float2 hex_to_cart(float3 cart) {

+  return float2(

+      cart[0] + (cart[1] + cart[2]) * 0.5f,

+      (cart[1] - cart[2]) * SQRT_3_OVER_2);

+}

+

 #endif  // __MATH_INC