oops, add instancing cginc

1 files changed, 22 insertions, 0 deletions

diff --git a/instancing.cginc b/instancing.cginc
new file mode 100644
index 0000000..eb8e25b
--- /dev/null
+++ b/instancing.cginc
@@ -0,0 +1,22 @@
+#ifndef __INSTANCING_INC
+#define __INSTANCING_INC
+
+#include "globals.cginc"
+#include "interpolators.cginc"
+
+void instance_distance_culling(inout v2f i) {
+#if defined(_INSTANCE_DISTANCE_CULLING)
+  // We want to measure the distance from the instance's transform to the camera.
+  float3 instance_pos = mul(unity_ObjectToWorld, float4(0, 0, 0, 1)).xyz;
+  float distance = length(_WorldSpaceCameraPos - instance_pos);
+  if (distance > _Instance_Distance_Culling_Distance) {
+    discard;
+  }
+#endif  // _INSTANCE_DISTANCE_CULLING
+}
+
+void instancing_frag(v2f i) {
+  instance_distance_culling(i);
+}
+
+#endif  // __INSTANCING_INC