Rework step size / density

Step size is now derived from density. Step size is reimagined as a
"quality" multiplier.

7 files changed, 25 insertions, 14 deletions

diff --git a/Editor/tooner.cs b/Editor/tooner.cs
index 9f689aa..fdcb678 100644
--- a/Editor/tooner.cs
+++ b/Editor/tooner.cs
@@ -2023,8 +2023,8 @@ public class ToonerGUI : ShaderGUI {
     RangeProperty(bc, "Density");
     bc = FindProperty("_Gimmick_Fog_00_Radius");
     FloatProperty(bc, "Radius");
-    bc = FindProperty("_Gimmick_Fog_00_Step_Size");
-    FloatProperty(bc, "Step size");
+    bc = FindProperty("_Gimmick_Fog_00_Step_Size_Factor");
+    FloatProperty(bc, "Step size multiplier");
     bc = FindProperty("_Gimmick_Fog_00_Max_Ray");
     FloatProperty(bc, "Max ray length (m)");
     bc = FindProperty("_Gimmick_Fog_00_Noise_Scale");
diff --git a/fog.cginc b/fog.cginc
index 6635ab7..f31a7d3 100644
--- a/fog.cginc
+++ b/fog.cginc
@@ -12,6 +12,7 @@
 struct Fog00PBR {
   float4 albedo;
   float3 normal;
+  float3 diffuse;
   float depth;
   float ao;
 };
@@ -95,26 +96,28 @@ Fog00PBR getFog00(v2f i) {
 
   // Factor of 10 on `screen_uv*10` eliminates visible striping artifact that
   // is visible with no factor.
-  float dither = rand2(screen_uv*10) * _Gimmick_Fog_00_Step_Size * _Gimmick_Fog_00_Ray_Origin_Randomization;
+  float step_size = rcp(_Gimmick_Fog_00_Density) * _Gimmick_Fog_00_Step_Size_Factor;
+  step_size = clamp(step_size, 1E-2, 10);
+  float dither = rand2(screen_uv*10) * step_size * _Gimmick_Fog_00_Ray_Origin_Randomization;
   ro += rd * (0.1 + dither);
 
   float world_pos_depth_hit_l = length(world_pos_depth_hit - ro);
 
   float4 acc = 0;
   uint step_count = floor(min(
-        _Gimmick_Fog_00_Max_Ray / _Gimmick_Fog_00_Step_Size,
-        world_pos_depth_hit_l / _Gimmick_Fog_00_Step_Size));
+        _Gimmick_Fog_00_Max_Ray / step_size,
+        world_pos_depth_hit_l / step_size));
   step_count *= (1 - no_intersection);
 
   float3 normal = i.normal;
   float ao = 0;
   for (uint ii = 0; ii < step_count; ii++) {
-    float3 p = ro + (rd * _Gimmick_Fog_00_Step_Size) * ii;
+    float3 p = ro + (rd * step_size) * ii;
 
-    float col_gray = 0.3;
+    const float col_gray = 0;
     const float map_p = map(p);
     float4 c = float4(col_gray, col_gray, col_gray, map_p);
-    c.a = saturate(c.a * _Gimmick_Fog_00_Density * _Gimmick_Fog_00_Step_Size);
+    c.a = saturate(c.a * _Gimmick_Fog_00_Density * step_size);
 
 #if defined(_GIMMICK_FOG_00_EMITTER_TEXTURE)
     // Project onto plane
@@ -150,11 +153,13 @@ Fog00PBR getFog00(v2f i) {
     ao = cur_ao * (1.0 - acc.a) + acc.a * ao;
 
     // Performance hack: stop blending normals after enough accumulation.
+#if 0
     if (acc.a < _Gimmick_Fog_00_Normal_Cutoff) {
       float3 n = get_normal(p, map_p);
       float n_interp = saturate(c.a * (1.0 - acc.a) * rcp(_Gimmick_Fog_00_Normal_Cutoff));
       normal = MY_BLEND_NORMALS(normal, n, n_interp);
     }
+#endif
     if (acc.a > _Gimmick_Fog_00_Albedo_Cutoff) {
       acc /= acc.a;
       break;
@@ -166,9 +171,10 @@ Fog00PBR getFog00(v2f i) {
   }
 
   Fog00PBR pbr;
-  pbr.albedo.rgb = acc.rgb;
+  pbr.albedo.rgb = 1;
   pbr.albedo.a = saturate(acc.a);
   pbr.ao = ao;
+  pbr.diffuse = acc.rgb;
 
 #if 1
   pbr.normal = normalize(normal);
diff --git a/globals.cginc b/globals.cginc
index b4b0c84..e76cc4f 100644
--- a/globals.cginc
+++ b/globals.cginc
@@ -708,7 +708,7 @@ float _Gimmick_AL_Chroma_00_Hue_Shift_Theta;
 #if defined(_GIMMICK_FOG_00)
 float _Gimmick_Fog_00_Max_Ray;
 float _Gimmick_Fog_00_Radius;
-float _Gimmick_Fog_00_Step_Size;
+float _Gimmick_Fog_00_Step_Size_Factor;
 float _Gimmick_Fog_00_Noise_Scale;
 float _Gimmick_Fog_00_Noise_Exponent;
 float _Gimmick_Fog_00_Density;
diff --git a/pbr.cginc b/pbr.cginc
index 9dad53f..c53a156 100644
--- a/pbr.cginc
+++ b/pbr.cginc
@@ -192,6 +192,7 @@ float4 getLitColor(
     float ao,
     // hack while i figure out view-dependent flickering in outlines
     bool enable_direct,
+    float3 diffuse_contrib,
     v2f i)
 {
   float3 specular_tint;
@@ -243,7 +244,7 @@ float4 getLitColor(
 #else
     direct_light.color = getDirectLightColor();
 #endif
-    indirect_light.diffuse = getIndirectDiffuse(i, vertexLightColor, normal);
+    indirect_light.diffuse = getIndirectDiffuse(i, vertexLightColor, normal) + diffuse_contrib;
     indirect_light.specular = getIndirectSpecular(i, view_dir, normal, smoothness,
         metallic, worldPos, uv);
   }
diff --git a/tooner.shader b/tooner.shader
index 820d466..d3999e9 100644
--- a/tooner.shader
+++ b/tooner.shader
@@ -621,7 +621,7 @@ Shader "yum_food/tooner"
     _Gimmick_Fog_00_Enable_Static("Enable fog 00", Float) = 0
     _Gimmick_Fog_00_Max_Ray("Max ray", Float) = 25
     _Gimmick_Fog_00_Radius("Radius", Float) = 25
-    _Gimmick_Fog_00_Step_Size("Step size (meters)", Float) = 1
+    _Gimmick_Fog_00_Step_Size_Factor("Step size (meters)", Float) = 1
     _Gimmick_Fog_00_Noise_Scale("Noise scale", Float) = 1
     _Gimmick_Fog_00_Noise_Exponent("Noise exponent", Float) = 2.0
     _Gimmick_Fog_00_Density("Density", Range(0,2)) = 1.0
diff --git a/tooner_lighting.cginc b/tooner_lighting.cginc
index 325ccb3..093a5af 100644
--- a/tooner_lighting.cginc
+++ b/tooner_lighting.cginc
@@ -2198,6 +2198,7 @@ float4 effect(inout v2f i, out float depth)
   float ao = 1;
 #endif
 
+  float3 diffuse_contrib = 0;
 #if defined(_GIMMICK_FOG_00)
   {
     Fog00PBR pbr = getFog00(i);
@@ -2205,6 +2206,7 @@ float4 effect(inout v2f i, out float depth)
     normal = pbr.normal;
     ao = pbr.ao;
     depth = pbr.depth;
+    diffuse_contrib += pbr.diffuse;
   }
 #endif
 
@@ -2232,7 +2234,8 @@ float4 effect(inout v2f i, out float depth)
 #endif
 
   float4 lit = getLitColor(vertex_light_color, albedo, i.worldPos, normal,
-      metallic, 1.0 - roughness, i.uv0, ao, /*enable_direct=*/true, i);
+      metallic, 1.0 - roughness, i.uv0, ao, /*enable_direct=*/true,
+      diffuse_contrib, i);
 
 #if defined(_GIMMICK_FLAT_COLOR)
   if (round(_Gimmick_Flat_Color_Enable_Dynamic)) {
diff --git a/tooner_outline_pass.cginc b/tooner_outline_pass.cginc
index 960039e..9c10999 100644
--- a/tooner_outline_pass.cginc
+++ b/tooner_outline_pass.cginc
@@ -316,7 +316,8 @@ fixed4 frag (v2f i) : SV_Target
       vertex_light_color,
       albedo, i.worldPos, i.normal,
       /*metallic=*/0, /*smoothness=*/0,
-      i.uv0, ao, /*enable_direct=*/false, i);
+      i.uv0, ao, /*enable_direct=*/false,
+      /*diffuse_contrib=*/0, i);
 
   result += albedo * _Outline_Emission_Strength;
 #if defined(_GIMMICK_AL_CHROMA_00)