fix: ship silpom comparison shader as SPIR-V

examples/silpom-ssdm-compare/README.md

@@ -56,6 +56,21 @@ xvfb-run -a scripts/smoke_examples.sh silpom-ssdm-compare
 - Meshes: thin front card for classic POM; extruded slab for SilPOM/SSDM
 - `gl_FragDepth` only pulls toward the camera (Vulkan RH_ZO)
 
+### Regenerating the shader
+
+The fragment stage ships as **committed SPIR-V** (`shaders/compare.frag.spv`),
+loaded with `gfx.loadMeshShaderSpv`, so the example needs no runtime compiler and
+renders the same stages on every host. After editing `shaders/compare.frag`,
+regenerate the committed artifact with:
+
+```sh
+glslc -o shaders/compare.frag.spv shaders/compare.frag
+```
+
+Hot reload (`eve_asset_reload`) recompiles the GLSL live through the engine's own
+compiler; where that is unavailable the panels keep the committed SPIR-V and the
+status line reports it.
+
 ## Honesty bound
 
 True screen-space SSDM as a deferred/post pass (pyramid mip + screen warp over

examples/silpom-ssdm-compare/main.nut

@@ -149,7 +149,14 @@ function makeThinMesh() {
 }
 
 function makeCard(mode, x) {
-    local shader = gfx.newMeshShader(fs.readText("shaders/compare.frag"));
+    // The fragment stage ships as committed SPIR-V next to its source, so the
+    // example needs no runtime compiler and every host renders the same stages.
+    // Regenerate with
+    //   glslc -o shaders/compare.frag.spv shaders/compare.frag
+    local loaded = gfx.loadMeshShaderSpv("", "shaders/compare.frag.spv");
+    if (!loaded.ok)
+        throw "silpom-ssdm-compare: compare.frag.spv unavailable: " + loaded.status.summary;
+    local shader = loaded.value;
     shader.declareFloat("mode");
     shader.declareFloat("scale");
     shader.declareFloat("minLayers");
@@ -277,12 +284,15 @@ eve_init = function() {
 eve_asset_reload <- function(path) {
     if (!cmpReady) return;
     if (path.find("compare.frag") == null) return;
+    // Live GLSL reload uses the engine's own compiler; when it is missing or the
+    // source fails to compile, the committed SPIR-V keeps rendering and the status
+    // line says so instead of failing the example.
     local src = fs.readText("shaders/compare.frag");
     foreach (p in [cmpPom, cmpSil, cmpSsdm]) {
         local result = gfx.replaceShaderFromGlsl(p.shader, "", src);
         if (!result.ok) {
-            cmpStatus = "compile failed";
-            print("[silpom-ssdm] compile failed\n");
+            cmpStatus = "GLSL reload failed; keeping committed SPIR-V";
+            print("[silpom-ssdm] " + cmpStatus + "\n");
             return;
         }
         syncPanel(p);

examples/silpom-ssdm-compare/shaders/compare.frag

@@ -258,7 +258,7 @@ void applySolidMarch(float mode, float scale, float minLayers, float maxLayers,
     shadow = mix(1.0, selfShadow(uv, 1.0 - hit.w, lightTS, scale,
                                  minLayers, maxLayers), 0.55);
     // Mild contact darkening in mortar trenches (reads depth without soft pillows).
-    float trench = smoothstep(0.85, 0.40, h);
+    float trench = 1.0 - smoothstep(0.40, 0.85, h);
     shadow *= mix(1.0, 0.72, trench);
 }
 

scripts/smoke_examples.sh

@@ -175,12 +175,15 @@ for name in "${EXAMPLES[@]}"; do
   if [[ -n "$reason" ]]; then
     echo "FAIL  $name  (${reason})"
     if [[ -n "$hit" ]]; then
-      grep -nF "$hit" "$log" 2>/dev/null | head -3 | sed 's/^/       /'
+      # Print the marker WITH context: a marker line alone hides the rest of a
+      # multi-line message (e.g. a compiler diagnostic on the following line),
+      # which is exactly what a CI reader needs to debug the failure.
+      grep -n -A 8 -F "$hit" "$log" 2>/dev/null | head -24 | sed 's/^/       /'
     fi
     echo "       --- key output (non-frame-error lines, head 30) ---"
     grep -vF "frame error" "$log" 2>/dev/null | head -n 30 | sed 's/^/       | /'
-    echo "       --- example output (last 10 lines) ---"
-    tail -n 10 "$log" | sed 's/^/       | /'
+    echo "       --- example output (last 30 lines) ---"
+    tail -n 30 "$log" | sed 's/^/       | /'
     FAILED=$((FAILED + 1))
     FAILED_NAMES+=("$name")
   else