1 files changed, 59 insertions, 0 deletions
diff --git a/source/blender/draw/intern/shaders/common_aabb_lib.glsl b/source/blender/draw/intern/shaders/common_aabb_lib.glsl
new file mode 100644
index 00000000000..b5f664a6779
--- /dev/null
+++ b/source/blender/draw/intern/shaders/common_aabb_lib.glsl
@@ -0,0 +1,59 @@
+
+#pragma BLENDER_REQUIRE(common_shape_lib.glsl)
+
+/* ---------------------------------------------------------------------- */
+/** \name Axis Aligned Bound Box
+ * \{ */
+
+struct AABB {
+  vec3 min, max;
+};
+
+AABB aabb_init_min_max()
+{
+  AABB aabb;
+  aabb.min = vec3(1.0e30);
+  aabb.max = vec3(-1.0e30);
+  return aabb;
+}
+
+void aabb_merge(inout AABB aabb, vec3 v)
+{
+  aabb.min = min(aabb.min, v);
+  aabb.max = max(aabb.max, v);
+}
+
+/**
+ * Return true if there is any intersection.
+ */
+bool aabb_intersect(AABB a, AABB b)
+{
+  return all(greaterThanEqual(min(a.max, b.max), max(a.min, b.min)));
+}
+
+/**
+ * Compute intersect intersection volume of \a a and \a b.
+ * Return true if the resulting volume is not empty.
+ */
+bool aabb_clip(AABB a, AABB b, out AABB c)
+{
+  c.min = max(a.min, b.min);
+  c.max = min(a.max, b.max);
+  return all(greaterThanEqual(c.max, c.min));
+}
+
+Box aabb_to_box(AABB aabb)
+{
+  Box box;
+  box.corners[0] = aabb.min;
+  box.corners[1] = vec3(aabb.max.x, aabb.min.y, aabb.min.z);
+  box.corners[2] = vec3(aabb.max.x, aabb.max.y, aabb.min.z);
+  box.corners[3] = vec3(aabb.min.x, aabb.max.y, aabb.min.z);
+  box.corners[4] = vec3(aabb.min.x, aabb.min.y, aabb.max.z);
+  box.corners[5] = vec3(aabb.max.x, aabb.min.y, aabb.max.z);
+  box.corners[6] = aabb.max;
+  box.corners[7] = vec3(aabb.min.x, aabb.max.y, aabb.max.z);
+  return box;
+}
+
+/** \} */