Update cloning

Optimize cloning logic, and make each clone rotate independently of the
others when the explosion effect is active.

1 files changed, 82 insertions, 10 deletions

diff --git a/clones.cginc b/clones.cginc
index 9b43b80..140e7d1 100644
--- a/clones.cginc
+++ b/clones.cginc
@@ -1,14 +1,70 @@
 #include "interpolators.cginc"
 #include "globals.cginc"
+#include "math.cginc"
 
 #ifndef __CLONES_INC
 #define __CLONES_INC
 
 #if defined(_CLONES)
 
-void add_clones(in v2f clone_verts[3], inout TriangleStream<v2f> tri_out)
+void rotate_triangle(inout v2f tri_in[3], const float pid_rand, const float phase)
 {
-  if (_Clones_dx < 1E-6) {
+  if (phase < 1E-6) {
+    return;
+  }
+
+  float3 avg_pos = (tri_in[0].worldPos + tri_in[1].worldPos + tri_in[2].worldPos) * .33333333;
+  tri_in[0].worldPos -= avg_pos;
+  tri_in[1].worldPos -= avg_pos;
+  tri_in[2].worldPos -= avg_pos;
+
+  if (phase > 1E-6) {
+    float theta = phase * 3.14159 * 4 + phase * (sin(_Time[1] * (1 + pid_rand) * 0.5 + pid_rand) + cos(_Time[1] * (1 + pid_rand) * .16393442 + pid_rand) * 2) * pid_rand * 2;
+    float3 axis = normalize(float3(
+          rand((int) ((tri_in[0].uv0.x + tri_in[0].uv0.y + pid_rand) * 1E9)) * 2 - 1,
+          rand((int) ((tri_in[1].uv0.x + tri_in[1].uv0.y + pid_rand) * 1E9)) * 2 - 1,
+          rand((int) ((tri_in[2].uv0.x + tri_in[2].uv0.y + pid_rand) * 1E9)) * 2 - 1));
+    float4 quat = get_quaternion(axis, theta);
+    tri_in[0].worldPos = rotate_vector(tri_in[0].worldPos, quat);
+    tri_in[1].worldPos = rotate_vector(tri_in[1].worldPos, quat);
+    tri_in[2].worldPos = rotate_vector(tri_in[2].worldPos, quat);
+  }
+
+  tri_in[0].worldPos *= _Clones_Scale.xyz;
+  tri_in[1].worldPos *= _Clones_Scale.xyz;
+  tri_in[2].worldPos *= _Clones_Scale.xyz;
+
+  tri_in[0].worldPos += avg_pos;
+  tri_in[1].worldPos += avg_pos;
+  tri_in[2].worldPos += avg_pos;
+
+  float3 v0_objPos = mul(unity_WorldToObject, float4(tri_in[0].worldPos, 1));
+  float3 v1_objPos = mul(unity_WorldToObject, float4(tri_in[1].worldPos, 1));
+  float3 v2_objPos = mul(unity_WorldToObject, float4(tri_in[2].worldPos, 1));
+
+  // Perf hack: Normal gets normalized in fragment shader anyway xdd
+  // TODO add a toggle to normalize in fragment or not; and use it to gate this
+  // optimization.
+  float3 n = cross(tri_in[1].worldPos - tri_in[0].worldPos, tri_in[2].worldPos - tri_in[0].worldPos);
+  tri_in[0].normal = n;
+  tri_in[1].normal = n;
+  tri_in[2].normal = n;
+
+  tri_in[0].pos = UnityObjectToClipPos(v0_objPos);
+  tri_in[1].pos = UnityObjectToClipPos(v1_objPos);
+  tri_in[2].pos = UnityObjectToClipPos(v2_objPos);
+
+  tri_in[0].objPos = v0_objPos;
+  tri_in[1].objPos = v1_objPos;
+  tri_in[2].objPos = v2_objPos;
+}
+
+void add_clones(in v2f clone_verts[3], inout TriangleStream<v2f> tri_out,
+    float pid_rand, float explode_phase)
+{
+  if (_Clones_dx < 1E-6 &&
+      _Clones_dy < 1E-6 &&
+      _Clones_dz < 1E-6) {
     return;
   }
 
@@ -21,16 +77,32 @@ void add_clones(in v2f clone_verts[3], inout TriangleStream<v2f> tri_out)
 
   uint n_clones = (uint) round(_Clones_Count);
   for (uint i = 0; i < (uint) n_clones; i++) {
+    v2f mod_verts[3] = clone_verts;
+    float3 offset = i;
+    offset = ((offset % 2) * 2 - 1) * (((offset) * 0.5) + 1) *
+      float3(_Clones_dx, _Clones_dy, _Clones_dz);
     for (uint j = 0; j < 3; j++) {
-      v2f ii = clone_verts[j];
-      float3 objPos = mul(unity_WorldToObject, float4(ii.worldPos, 1)).xyz;
-      float offset = i;
-      offset = ((offset % 2) * 2 - 1) * (((offset) / 2) + 1) * _Clones_dx;
-      objPos.x += offset;
-      ii.worldPos = mul(unity_ObjectToWorld, float4(objPos, 1)).xyz;
-      ii.pos = UnityObjectToClipPos(objPos);
-      tri_out.Append(ii);
+#if 0
+      float3 objPos = mul(unity_WorldToObject, float4(mod_verts[j].worldPos, 1)).xyz;
+      objPos += offset;
+      mod_verts[j].worldPos = mul(unity_ObjectToWorld, float4(objPos, 1)).xyz;
+#else
+      mod_verts[j].worldPos += offset;
+#endif
     }
+#if 1
+    rotate_triangle(mod_verts, rand(pid_rand+i), /*phase=*/1);
+#else
+    mod_verts[0].objPos = mul(unity_WorldToObject, float4(mod_verts[0].worldPos, 1));
+    mod_verts[1].objPos = mul(unity_WorldToObject, float4(mod_verts[1].worldPos, 1));
+    mod_verts[2].objPos = mul(unity_WorldToObject, float4(mod_verts[2].worldPos, 1));
+    mod_verts[0].pos = UnityObjectToClipPos(mod_verts[0].objPos);
+    mod_verts[1].pos = UnityObjectToClipPos(mod_verts[1].objPos);
+    mod_verts[2].pos = UnityObjectToClipPos(mod_verts[2].objPos);
+#endif
+    tri_out.Append(mod_verts[0]);
+    tri_out.Append(mod_verts[1]);
+    tri_out.Append(mod_verts[2]);
     tri_out.RestartStrip();
   }
 }