From 0d7e2444c55eb2067792c6da57dad370e997fa4d Mon Sep 17 00:00:00 2001
From: yum <yum.food.vr@gmail.com>
Date: Sun, 2 Nov 2025 18:10:55 -0800
Subject: add hex grid tiling

---
 math.cginc | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

(limited to 'math.cginc')

diff --git a/math.cginc b/math.cginc
index 58a9c08..f188a91 100644
--- a/math.cginc
+++ b/math.cginc
@@ -74,5 +74,20 @@ float2 hex_to_cart(float3 cart) {
       (cart[1] - cart[2]) * SQRT_3_OVER_2);
 }
 
+
+float3 round_hex(float3 hex_coord) {
+    float3 rounded = round(hex_coord);
+    float3 diff = abs(rounded - hex_coord);
+    float error = rounded.x - rounded.y - rounded.z;
+
+    float3 max_mask = float3(
+        diff.x > diff.y && diff.x > diff.z,
+        diff.y > diff.x && diff.y > diff.z,
+        diff.z > diff.x && diff.z > diff.y);
+
+    rounded += error * float3(-1, 1, 1) * max_mask;
+    return rounded;
+}
+
 #endif  // __MATH_INC
 
-- 
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