diff --git a/src/gpu/gpu_dx12/gpu_dx12_core.c b/src/gpu/gpu_dx12/gpu_dx12_core.c
index eb327a08..6cbcef21 100644
--- a/src/gpu/gpu_dx12/gpu_dx12_core.c
+++ b/src/gpu/gpu_dx12/gpu_dx12_core.c
@@ -3156,7 +3156,6 @@ void G_D12_CollectionWorkerEntryPoint(WaveLaneCtx *lane)
                     FmtArg *dst = &args.args[arg_idx];
                     switch (gpu_kind)
                     {
-
                       // Translate unsigned integer args
                       case G_FmtArgKind_Uint:
                       {
@@ -3235,6 +3234,7 @@ void G_D12_CollectionWorkerEntryPoint(WaveLaneCtx *lane)
                         at += 16;
                       } break;
                     }
+                    dst->p = 6;
                   }
                 }
               }
diff --git a/src/pp/pp_sim/pp_sim_core.c b/src/pp/pp_sim/pp_sim_core.c
index bb7cbe76..9b6a4e36 100644
--- a/src/pp/pp_sim/pp_sim_core.c
+++ b/src/pp/pp_sim/pp_sim_core.c
@@ -1615,7 +1615,7 @@ void S_TickForever(WaveLaneCtx *lane)
 
           // i64 tick_bullets_count = sim_dt * firer->fire_rate;
 
-          f32 fire_rate = 20;
+          f32 fire_rate = 50;
           f32 bullets_per_fire = 1;
           // f32 spread = Tau * 0.05;
           f32 spread = Tau * 0.01;
diff --git a/src/pp/pp_vis/pp_vis_core.c b/src/pp/pp_vis/pp_vis_core.c
index 9a1c1a0f..403151b4 100644
--- a/src/pp/pp_vis/pp_vis_core.c
+++ b/src/pp/pp_vis/pp_vis_core.c
@@ -354,11 +354,13 @@ void V_TickForever(WaveLaneCtx *lane)
   G_ResourceHandle gpu_particles = Zi;
   G_ResourceHandle gpu_cells = Zi;
   G_ResourceHandle gpu_stains = Zi;
+  G_ResourceHandle gpu_drynesses = Zi;
   G_RWStructuredBufferRef gpu_state_ref = Zi;
   G_Texture2DRef gpu_tiles_ref = Zi;
   G_RWStructuredBufferRef gpu_particles_ref = Zi;
   G_RWTexture2DRef gpu_cells_ref = Zi;
   G_RWTexture2DRef gpu_stains_ref = Zi;
+  G_RWTexture2DRef gpu_drynesses_ref = Zi;
   {
     G_CommandListHandle cl = G_PrepareCommandList(G_QueueKind_Direct);
     {
@@ -421,6 +423,21 @@ void V_TickForever(WaveLaneCtx *lane)
         );
         gpu_stains_ref = G_PushRWTexture2DRef(gpu_perm, gpu_stains);
       }
+      // Init drynesses texture
+      {
+        gpu_drynesses = G_PushTexture2D(
+          gpu_perm, cl,
+          // G_Format_R8_Uint,
+          // G_Format_R11G11B10_Float,
+          // G_Format_R10G10B10A2_Unorm,
+          // G_Format_R16_Float,
+          G_Format_R32_Float,
+          cells_dims,
+          G_Layout_DirectQueue_ShaderReadWrite,
+          .flags = G_ResourceFlag_ZeroMemory | G_ResourceFlag_AllowShaderReadWrite
+        );
+        gpu_drynesses_ref = G_PushRWTexture2DRef(gpu_perm, gpu_drynesses);
+      }
     }
     G_CommitCommandList(cl);
   }
@@ -2988,6 +3005,8 @@ void V_TickForever(WaveLaneCtx *lane)
       emitter.end = emitter.start;
       emitter.angle = AngleFromVec2(dir);
 
+      // emitter.flags |= V_ParticleFlag_StainTrail;
+
       emitter.count = 128;
       // emitter.count = 100;
       emitter.speed = 10;
@@ -3175,6 +3194,7 @@ void V_TickForever(WaveLaneCtx *lane)
         params.should_clear_stains = should_clear_particles;
         params.cells = gpu_cells_ref;
         params.stains = gpu_stains_ref;
+        params.drynesses = gpu_drynesses_ref;
       }
       G_ResourceHandle gpu_params = G_PushBufferFromCpuCopy(frame->gpu_arena, frame->cl, StringFromStruct(&params));
       G_StructuredBufferRef gpu_params_ref = G_PushStructuredBufferRef(frame->gpu_arena, gpu_params, V_GpuParams);
diff --git a/src/pp/pp_vis/pp_vis_gpu.g b/src/pp/pp_vis/pp_vis_gpu.g
index 559c266a..4c1d4757 100644
--- a/src/pp/pp_vis/pp_vis_gpu.g
+++ b/src/pp/pp_vis/pp_vis_gpu.g
@@ -1,3 +1,22 @@
+////////////////////////////////////////////////////////////
+//~ Helpers
+
+f32 V_RandFromPos(Vec3 pos)
+{
+  Texture3D<u32> noise3d = G_Dereference<u32>(V_ShaderConst_NoiseTex);
+  Vec3I32 dims = countof(noise3d);
+  u32 noise = noise3d[floor(pos) % dims];
+  f32 rand = (f32)noise / 0xFFFF;
+  return rand;
+}
+
+Vec4 V_DryColor(Vec4 color, f32 dryness)
+{
+  Vec4 result = color;
+  result.rgb *= 1.0 - (dryness * 0.75);
+  return result;
+}
+
 ////////////////////////////////////////////////////////////
 //~ Utility shaders
 
@@ -7,13 +26,26 @@ ComputeShader2D(V_ClearCellsCS, 8, 8)
   V_GpuParams params = G_Dereference<V_GpuParams>(V_ShaderConst_Params)[0];
   RWTexture2D<Vec4> cells = G_Dereference<Vec4>(params.cells);
   RWTexture2D<Vec4> stains = G_Dereference<Vec4>(params.stains);
+  RWTexture2D<f32> drynesses = G_Dereference<f32>(params.drynesses);
   Vec2 cells_idx = SV_DispatchThreadID;
   if (cells_idx.x < countof(cells).x && cells_idx.y < countof(cells).y)
   {
+    // Clear cell
     cells[cells_idx] = 0;
+
+    // Clear stain
     if (params.should_clear_stains)
     {
       stains[cells_idx] = 0;
+      drynesses[cells_idx] = 0;
+    }
+
+    // Increase dryness
+    f32 dry_rate = params.dt * 0.1;
+    {
+      f32 old_dryness = drynesses[cells_idx];
+      f32 new_dryness = lerp(old_dryness, 1, dry_rate);
+      drynesses[cells_idx] = new_dryness;
     }
   }
 }
@@ -159,10 +191,16 @@ ComputeShader2D(V_BackdropCS, 8, 8)
       {
         RWTexture2D<Vec4> stains = G_Dereference<Vec4>(params.stains);
         RWTexture2D<Vec4> cells = G_Dereference<Vec4>(params.cells);
+        RWTexture2D<f32> drynesses = G_Dereference<f32>(params.drynesses);
+
         Vec2 cell_pos = floor(mul(params.xf.world_to_cell, Vec3(world_pos, 1)));
 
         Vec4 stain = stains.Load(cell_pos);
         Vec4 cell = cells.Load(cell_pos);
+        f32 dryness = drynesses[cell_pos];
+
+        stain = V_DryColor(stain, dryness);
+
         // cell.rgb *= cell.a;
         // stain.rgb *= stain.a;
 
@@ -317,6 +355,7 @@ ComputeShader(V_SimParticlesCS, 64)
   RWStructuredBuffer<V_Particle> particles = G_Dereference<V_Particle>(params.particles);
   RWTexture2D<Vec4> cells = G_Dereference<Vec4>(params.cells);
   RWTexture2D<Vec4> stains = G_Dereference<Vec4>(params.stains);
+  RWTexture2D<f32> drynesses = G_Dereference<f32>(params.drynesses);
 
   u32 particle_idx = SV_DispatchThreadID;
   if (particle_idx < V_MaxParticles)
@@ -403,17 +442,18 @@ ComputeShader(V_SimParticlesCS, 64)
           cells[cell_pos] = color;
           if (should_stain)
           {
-            // stains[cell_pos] = color;
-
-
+            f32 old_dryness = drynesses[cell_pos];
             Vec4 old_stain = stains[cell_pos];
-
+            // old_stain = V_DryColor(old_stain, drynesses[cell_pos] * 0.5);
+            // old_stain = V_DryColor(old_stain, old_dryness);
             Vec4 new_stain = 0;
-            new_stain.rgb = (old_stain.rgb * old_stain.a) + (color.rgb * (1.0 - old_stain.a));
-            new_stain.a = color.a = (old_stain.a * 1) + (color.a * (1.0 - old_stain.a));
-
+            new_stain.rgb = (color.rgb * color.a) + (old_stain.rgb * (1.0 - color.a));
+            new_stain.a = color.a + (old_stain.a * (1.0 - color.a));
+            // new_stain = V_DryColor(new_stain, old_dryness * 0.1);
+            // new_stain = V_DryColor(new_stain, old_dryness * 0.5);
 
             stains[cell_pos] = new_stain;
+            drynesses[cell_pos] = 0;
           }
         }
         else
diff --git a/src/pp/pp_vis/pp_vis_gpu.gh b/src/pp/pp_vis/pp_vis_gpu.gh
index 4a0d1e24..7d112c30 100644
--- a/src/pp/pp_vis/pp_vis_gpu.gh
+++ b/src/pp/pp_vis/pp_vis_gpu.gh
@@ -40,6 +40,12 @@ Struct(V_OverlayPSOutput)
   Semantic(Vec4, sv_target0);
 };
 
+////////////////////////////////////////////////////////////
+//~ Helpers
+
+f32 V_RandFromPos(Vec3 pos);
+Vec4 V_DryColor(Vec4 color, f32 dryness);
+
 ////////////////////////////////////////////////////////////
 //~ Shaders
 
diff --git a/src/pp/pp_vis/pp_vis_shared.cgh b/src/pp/pp_vis/pp_vis_shared.cgh
index c951607e..2405551a 100644
--- a/src/pp/pp_vis/pp_vis_shared.cgh
+++ b/src/pp/pp_vis/pp_vis_shared.cgh
@@ -83,6 +83,7 @@ Struct(V_GpuParams)
   b32 should_clear_stains;
   G_RWTexture2DRef cells;
   G_RWTexture2DRef stains;
+  G_RWTexture2DRef drynesses;
 };
 
 ////////////////////////////////////////////////////////////