Refine origin damping behavior, fix normals precision

1E-3 is much too coarse for normal calculation.

5 files changed, 24 insertions, 4 deletions

diff --git a/Editor/tooner.cs b/Editor/tooner.cs
index 62d0032..2a6d805 100644
--- a/Editor/tooner.cs
+++ b/Editor/tooner.cs
@@ -2173,6 +2173,8 @@ public class ToonerGUI : ShaderGUI {
     FloatProperty(bc, "g");
     bc = FindProperty("_Gimmick_Gerstner_Water_Scale");
     VectorProperty(bc, "Scale");
+    bc = FindProperty("_Gimmick_Gerstner_Water_Origin_Damping_Direction");
+    FloatProperty(bc, "Origin damping direction");
 
     EditorGUI.indentLevel -= 1;
   }
diff --git a/gerstner.cginc b/gerstner.cginc
index da7d2f5..e6ed3c2 100644
--- a/gerstner.cginc
+++ b/gerstner.cginc
@@ -102,10 +102,23 @@ float3 compute_gerstner(float3 pp, GerstnerParams p)
   }
 
   const float3 raw_result = float3(g_xi / p.scale.x, g_eta / p.scale.y, g_zeta * p.scale.z);
-  const float origin_damping_factor = 1 - pow(0.5, max(0, length(raw_result)*5000-2));
+  const float3 raw_result_world = mul(unity_ObjectToWorld, float4(raw_result, 1)).xyz;
+  float3 result_world = raw_result_world;
 
-  float3 result = raw_result;
-  result.z *= origin_damping_factor;
+  if (_Gimmick_Gerstner_Water_Origin_Damping_Direction > 0) {
+    result_world.y = max(_Gimmick_Gerstner_Water_Origin_Damping_Direction, result_world.y);
+  } else {
+    result_world.y = min(_Gimmick_Gerstner_Water_Origin_Damping_Direction, result_world.y);
+  }
+
+  result_world.y = lerp(result_world.y, raw_result_world.y,
+      // If within 20m cylindrical distance, apply 100m wide damping.
+      // TODO parameterize this!
+      saturate((length(raw_result_world.xz) - 20) * 0.01) *
+      // Only enable if mesh is on the wrong side of the damping vector.
+      (sign(raw_result_world.y - _Gimmick_Gerstner_Water_Origin_Damping_Direction) != sign(_Gimmick_Gerstner_Water_Origin_Damping_Direction)));
+
+  float3 result = mul(unity_WorldToObject, float4(result_world, 1)).xyz;
   return result;
 }
 
@@ -117,7 +130,7 @@ float3 gerstner_vert(float3 pp, GerstnerParams p)
 float3 gerstner_frag(float3 pp, GerstnerParams p)
 {
   const float3 g0 = compute_gerstner(pp, p);
-  const float3 e = float3(.001, 0, 0);
+  const float3 e = float3(1E-8, 0, 0);
   const float3 g0_da = compute_gerstner(pp + e.xyz, p);
   const float3 g0_db = compute_gerstner(pp + e.yxz, p);
   const float3 ds_da = g0_da - g0;
diff --git a/globals.cginc b/globals.cginc
index 044d9fe..6800b7b 100644
--- a/globals.cginc
+++ b/globals.cginc
@@ -752,6 +752,7 @@ float4 _Gimmick_Gerstner_Water_p;
 float4 _Gimmick_Gerstner_Water_k_x;
 float4 _Gimmick_Gerstner_Water_k_y;
 float4 _Gimmick_Gerstner_Water_t_f;
+float _Gimmick_Gerstner_Water_Origin_Damping_Direction;
 #if defined(_GIMMICK_GERSTNER_WATER_OCTAVE_1)
 float4 _Gimmick_Gerstner_Water_a1;
 float4 _Gimmick_Gerstner_Water_p1;
diff --git a/tooner.shader b/tooner.shader
index bb9a65a..f6beeee 100644
--- a/tooner.shader
+++ b/tooner.shader
@@ -673,6 +673,7 @@ Shader "yum_food/tooner"
     _Gimmick_Gerstner_Water_h("Mean water depth", Float) = 10
     _Gimmick_Gerstner_Water_g("Gravity", Float) = 9.8
     _Gimmick_Gerstner_Water_Scale("Scale", Vector) = (1000, 1000, .1)
+    _Gimmick_Gerstner_Water_Origin_Damping_Direction("Origin damping direction", Float) = 1
   }
   SubShader
   {
diff --git a/tooner_lighting.cginc b/tooner_lighting.cginc
index 5d055c0..87cf2e4 100644
--- a/tooner_lighting.cginc
+++ b/tooner_lighting.cginc
@@ -1297,6 +1297,9 @@ float4 effect(inout v2f i, out float depth)
   }
 #endif
 #if defined(_GIMMICK_GERSTNER_WATER)
+#if defined(_EXPLODE)
+  if (_Explode_Phase < 1E-6)
+#endif
   {
     GerstnerParams p = getGerstnerParams();
     i.normal = UnityObjectToWorldNormal(gerstner_frag(i.objPos.xyz, p));