idk

.vscode/launch.json

@@ -27,7 +27,7 @@
         },
         {
             "name": "Editor (Linux)",
-            "type": "cppdbg",
+            "type": "lldb",
             "request": "launch",
             "program": "${workspaceRoot}/build/Editor",
             "args": [],

res/shaders/fluid/SignedDistance.slang

@@ -31,17 +31,17 @@ void reinitialize(uint3 dispatchThreadID : SV_DispatchThreadID)
     float dx = 1.0f;
 
     // Current value and original sign
-    float p = phi[x, y, z];
+    float p = phi0[x, y, z];
     float s = smoothSign(phi0[x, y, z], dx);
 
-    // Upwind finite differences for |grad phi|
+    // Upwind finite differences for |grad phi| — read from snapshot to avoid race
     // Forward and backward differences
-    float dxp = phi[x + 1, y, z] - p;
-    float dxm = p - phi[x - 1, y, z];
-    float dyp = phi[x, y + 1, z] - p;
-    float dym = p - phi[x, y - 1, z];
-    float dzp = phi[x, y, z + 1] - p;
-    float dzm = p - phi[x, y, z - 1];
+    float dxp = phi0[x + 1, y, z] - p;
+    float dxm = p - phi0[x - 1, y, z];
+    float dyp = phi0[x, y + 1, z] - p;
+    float dym = p - phi0[x, y - 1, z];
+    float dzp = phi0[x, y, z + 1] - p;
+    float dzm = p - phi0[x, y, z - 1];
 
     // Godunov upwind scheme
     float gradPhi;

src/Engine/Graphics/RenderPass/SimulationComputePass.cpp

@@ -350,6 +350,11 @@ void SimulationComputePass::render() {
         Gfx::PShaderBuffer pressureNext = data.velocityZBuffer;
         divergencePass(divergence, pressureCurrent, data.velocityX0Buffer, data.velocityY0Buffer, data.velocityZ0Buffer, data.gridSize);
 
+        // Divergence/pressure buffers are aliased to velocity buffers whose boundary
+        // cells still contain stale velocity data.  Zero the boundaries before solving.
+        setBoundsPass(divergence, 0, data.gridSize);
+        setBoundsPass(pressureCurrent, 0, data.gridSize);
+
         for (int iteration = 0; iteration < pressureSolveIterations; ++iteration) {
             linearSolvePass(pressureNext, pressureCurrent, divergence, 1, 6, data.gridSize);
 
@@ -388,6 +393,9 @@ void SimulationComputePass::render() {
         Gfx::PShaderBuffer advectedPressureCurrent = data.velocityYNextBuffer;
         Gfx::PShaderBuffer advectedPressureNext = data.velocityZNextBuffer;
         divergencePass(advectedDivergence, advectedPressureCurrent, data.velocityXBuffer, data.velocityYBuffer, data.velocityZBuffer, data.gridSize);
+        setBoundsPass(advectedDivergence, 0, data.gridSize);
+        setBoundsPass(advectedPressureCurrent, 0, data.gridSize);
+
         for (int iteration = 0; iteration < pressureSolveIterations; ++iteration) {
             linearSolvePass(advectedPressureNext, advectedPressureCurrent, advectedDivergence, 1, 6, data.gridSize);
             setBoundsPass(advectedPressureNext, 0, data.gridSize);

vcpkg.json

@@ -1,5 +1,6 @@
 {
   "dependencies": [
+    "vulkan",
     {
       "name": "vulkan-memory-allocator"
     },