diff --git a/all.h b/all.h
index 7e06230..8801063 100644
--- a/all.h
+++ b/all.h
@@ -364,6 +364,12 @@ typedef struct Box {
   u32 width;
 } Box;
 
+typedef struct XYZ {
+  i32 x;
+  i32 y;
+  i32 z;
+} XYZ;
+
 typedef struct Dim2 {
   u16 height;
   u16 width;
@@ -545,6 +551,9 @@ global const u8  MAX_u8  = 0xff;
 #ifndef PI
 #define PI (3.14159265358979323846)
 #endif
+#ifndef SQRT_3
+# define SQRT_3 (1.7320508076)
+#endif
 
 ///// CUSTOM ENTRY POINT
 /* TODO?
@@ -556,6 +565,7 @@ fn b32 update(void);
 */
 
 ///// MATH
+fn bool xyzEq(XYZ a, XYZ b);
 fn Range1u64 range1u64Create(u64 min, u64 max);
 fn Range1u64 mRangeFromNIdxMCount(u64 n_idx, u64 n_count, u64 m_count);
 fn void u32Quicksort(u32 arr[], u32 low, u32 high);
diff --git a/math.c b/math.c
index 1035af0..dd52e7d 100644
--- a/math.c
+++ b/math.c
@@ -1,5 +1,11 @@
 #include "all.h"
 
+fn bool xyzEq(XYZ a, XYZ b) {
+  return a.x == b.x &&
+    a.y == b.y &&
+    a.z == b.z;
+}
+
 fn Range1u64 range1u64Create(u64 min, u64 max) {
   Range1u64 result = {
     .min = min,