From 2c9e02770250a3f3e781a2fb22357e0a910a2436 Mon Sep 17 00:00:00 2001
From: yum <yum.food.vr@gmail.com>
Date: Fri, 28 Mar 2025 16:09:34 -0700
Subject: add rotation to shatterwave

---
 2ner.shader        |  4 ++++
 features.cginc     |  4 ++++
 globals.cginc      |  4 ++++
 shatter_wave.cginc | 20 +++++++++++++++++---
 4 files changed, 29 insertions(+), 3 deletions(-)

diff --git a/2ner.shader b/2ner.shader
index 732fd7d..9840230 100644
--- a/2ner.shader
+++ b/2ner.shader
@@ -523,6 +523,10 @@ Shader "yum_food/2ner"
             _Shatter_Wave_Chronotensity_Weights2("Chronotensity weights (wave 2)", Vector) = (0, 0, 0, 0)
             _Shatter_Wave_Chronotensity_Weights3("Chronotensity weights (wave 3)", Vector) = (0, 0, 0, 0)
           [HideInInspector] m_end_Shatter_Wave_Audiolink("Audiolink", Float) = 0
+          [HideInInspector] m_start_Shatter_Wave_Rotation("Rotation", Float) = 0
+            [ThryToggle(_SHATTER_WAVE_ROTATION)] _Shatter_Wave_Rotation_Enabled("Enable", Float) = 0
+            _Shatter_Wave_Rotation_Strength("Strength", Vector) = (1.0, 1.0, 1.0, 1.0)
+          [HideInInspector] m_end_Shatter_Wave_Rotation("Rotation", Float) = 0
         [HideInInspector] m_end_Shatter_Wave("Shatter wave", Float) = 0
         //endex
 
diff --git a/features.cginc b/features.cginc
index 807ae84..a74b4f7 100644
--- a/features.cginc
+++ b/features.cginc
@@ -204,6 +204,10 @@
 #pragma shader_feature_local _SHATTER_WAVE_AUDIOLINK
 //endex
 
+//ifex _Shatter_Wave_Rotation_Enabled==0
+#pragma shader_feature_local _SHATTER_WAVE_ROTATION
+//endex
+
 //ifex _Mirror_UVs_In_Mirror_Enabled==0
 #pragma shader_feature_local _MIRROR_UVS_IN_MIRROR
 //endex
diff --git a/globals.cginc b/globals.cginc
index e5ab929..5f891c3 100644
--- a/globals.cginc
+++ b/globals.cginc
@@ -436,6 +436,10 @@ float4 _Shatter_Wave_Chronotensity_Weights2;
 float4 _Shatter_Wave_Chronotensity_Weights3;
 #endif  // _SHATTER_WAVE_AUDIOLINK
 
+#if defined(_SHATTER_WAVE_ROTATION)
+float4 _Shatter_Wave_Rotation_Strength;
+#endif  // _SHATTER_WAVE_ROTATION
+
 #if defined(_TESSELLATION)
 float _Tessellation_Factor;
 #endif  // _TESSELLATION
diff --git a/shatter_wave.cginc b/shatter_wave.cginc
index 89b8e75..aae45ef 100644
--- a/shatter_wave.cginc
+++ b/shatter_wave.cginc
@@ -68,10 +68,24 @@ void shatterWaveVert(inout float3 objPos, float3 objNormal, float3 objTangent) {
   wave_t = fmod(wave_t + _Shatter_Wave_Time_Offset * _Shatter_Wave_Period, _Shatter_Wave_Period) - _Shatter_Wave_Period * 0.5;
 
   float4 wave_center = wave_t;
-  float4 offset;
+
+  // TODO calculate signed distance from wave center
+  float4 distance_signed;
+  for (uint i = 0; i < 4; i++) {
+    float3 dist_to_center = objPos_proj[i] - wave_center[i] * wave_axes[i];
+    distance_signed[i] = dot(dist_to_center, wave_axes[i]);
+  }
+
+#if defined(_SHATTER_WAVE_ROTATION)
+  float4 thetas = clamp(distance_signed * _Shatter_Wave_Rotation_Strength, -1, 1) * TAU;
+  for (uint i = 0; i < 4; i++) {
+    objPos = rotate_vector(objPos, get_quaternion(wave_axes[i], thetas[i]));
+  }
+#endif
+
   for (uint i = 0; i < 4; i++) {
-    offset[i] = exp(-length(objPos_proj[i] - wave_center[i] * wave_axes[i]) * _Shatter_Wave_Power[i]) * _Shatter_Wave_Amplitude[i];
-    objPos += objNormal * offset[i];
+    float offset = exp(-abs(distance_signed[i]) * _Shatter_Wave_Power[i]) * _Shatter_Wave_Amplitude[i];
+    objPos += objNormal * offset;
   }
 }
 
-- 
cgit v1.2.3