Add instancing distance culling, scale deformation

* GPU instance distance culling now takes a min/max range
* Fold recovers ops from material, allowing state to persist across
  editor restarts
* Add scale node to vertex deformation framework
* Remove fold presets - dumb LLM idea, unused
* Drop more "undeform" code; unused, was for ray marching, which does
  not work well
* Fix reflection energy compensation; was using cloth math, which makes
  things too bright

1 files changed, 28 insertions, 10 deletions

diff --git a/3ner.cginc b/3ner.cginc
index e675bc2..cf03caf 100755
--- a/3ner.cginc
+++ b/3ner.cginc
@@ -31,11 +31,32 @@ v2f vert(appdata v) {
   UNITY_TRANSFER_INSTANCE_ID(v, o);
   UNITY_INITIALIZE_VERTEX_OUTPUT_STEREO(o);
 
-  // Apply instance texture offset transformation if enabled
+  impostor_vert(v.vertex.xyz);
+
+#if defined(_VERTEX_DEFORMATION) && ( \
+        defined(_VERTEX_DEFORMATION_FRAGMENT_NORMALS) || \
+        defined(_VERTEX_DEFORMATION_TESSELLATION)) || \
+    (defined(_IMPOSTORS) && defined(_INSTANCE_TEXTURE_OFFSET))
+  o.objPos_orig = v.vertex;
+#endif
+
+
+  [branch] if (instance_distance_culling()) {
+    return (v2f) asfloat(-1);
+  }
   instancing_vert(v);
 
-#if defined(_IMPOSTORS)
-  impostor_vert(v.vertex.xyz);
+#if defined(_INSTANCE_TEXTURE_OFFSET) && defined(UNITY_INSTANCING_ENABLED)
+  // Early exit custom frustum culling.
+  float3 instanceCenter;
+  if (get_instance_center(instanceCenter)) {
+    float4 instanceClipPos = UnityObjectToClipPos(instanceCenter);
+    instanceClipPos /= instanceClipPos.w;
+    float k = 1.05;
+    if (any(instanceClipPos.xy < -k) || any(instanceClipPos.xy > k)) {
+      return (v2f) asfloat(-1);
+    }
+  }
 #endif
 
 #if defined(_TESSELLATION)
@@ -47,9 +68,6 @@ v2f vert(appdata v) {
   o.uv23.zw = v.uv3;
   float3 obj_space_camera_pos = mul(unity_WorldToObject, float4(_WorldSpaceCameraPos, 1.0));
   o.objPos = v.vertex;
-#if defined(_VERTEX_DEFORMATION_FRAGMENT_NORMALS) || defined(_VERTEX_DEFORMATION_TESSELLATION)
-  o.objPos_orig = v.vertex;
-#endif
 #if defined(_RAY_MARCHING_BAKED_ORIGINS)
   o.color = v.color;
 #endif
@@ -190,7 +208,10 @@ v2f domain(
   o.objPos   = DOMAIN_INTERP(objPos);
 #endif
 
-#if defined(_VERTEX_DEFORMATION_FRAGMENT_NORMALS) || defined(_VERTEX_DEFORMATION_TESSELLATION)
+#if defined(_VERTEX_DEFORMATION) && ( \
+        defined(_VERTEX_DEFORMATION_FRAGMENT_NORMALS) || \
+        defined(_VERTEX_DEFORMATION_TESSELLATION)) || \
+    defined(_IMPOSTORS) && defined(_INSTANCE_TEXTURE_OFFSET)
   o.objPos_orig = DOMAIN_INTERP(objPos_orig);
   o.objPos = o.objPos_orig;
   deform(o.objPos);
@@ -266,9 +287,6 @@ float4 frag(v2f i, uint facing : SV_IsFrontFace
   return 0;
 #endif
 
-  // Apply instancing effects (e.g., distance culling)
-  instancing_frag(i);
-
 #if defined(_RAY_MARCHING)
   const bool is_fragment = true;
   ray_march(i, is_fragment);