--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/thirdparty/freeglut/progs/demos/spaceball/vmath.c	Mon Sep 15 11:44:09 2025 +0200
@@ -0,0 +1,16 @@
+#include <math.h>
+#include "vmath.h"
+
+quat_t quat_rotate(quat_t q, float angle, float x, float y, float z)
+{
+  quat_t rq;
+  float half_angle = angle * 0.5f;
+  float sin_half = (float)sin(half_angle);
+
+  rq.w = (float)cos(half_angle);
+  rq.x = x * sin_half;
+  rq.y = y * sin_half;
+  rq.z = z * sin_half;
+
+  return quat_mul(q, rq);
+}