Multi pass test

shaders/gaussian-blur/shader.json

@@ -1,9 +1,25 @@
 {
   "id": "gaussian-blur",
   "name": "Gaussian Blur",
-  "description": "Applies a simple Gaussian-style blur to the decoded video input.",
+  "description": "Applies a separable two-pass Gaussian-style blur to the decoded video input.",
   "category": "Transform",
   "entryPoint": "shadeVideo",
+  "passes": [
+    {
+      "id": "horizontal",
+      "source": "shader.slang",
+      "entryPoint": "blurHorizontal",
+      "inputs": ["layerInput"],
+      "output": "blurHorizontal"
+    },
+    {
+      "id": "vertical",
+      "source": "shader.slang",
+      "entryPoint": "blurVertical",
+      "inputs": ["blurHorizontal"],
+      "output": "layerOutput"
+    }
+  ],
   "parameters": [
     {
       "id": "radius",

shaders/gaussian-blur/shader.slang

@@ -1,26 +1,23 @@
-float4 shadeVideo(ShaderContext context)
+float4 gaussianBlurDirection(ShaderContext context, float2 direction)
 {
 	float2 texel = 1.0 / max(context.inputResolution, float2(1.0, 1.0));
-	float blurRadius = max(radius, 0.0);
-	float2 sampleStep = texel * blurRadius;
+	float blurRadius = max(radius, 0.0) * saturate(strength);
+	float2 sampleStep = texel * blurRadius * direction;
 	int sampleRadius = int(clamp(samples, 0.0, 8.0) + 0.5);
 
 	float4 center = sampleVideo(context.uv);
 	float4 blur = float4(0.0, 0.0, 0.0, 0.0);
 	float totalWeight = 0.0;
 
-	for (int y = -sampleRadius; y <= sampleRadius; ++y)
-	{
 	for (int x = -sampleRadius; x <= sampleRadius; ++x)
 	{
-			float distanceSquared = float(x * x + y * y);
+		float distanceSquared = float(x * x);
 		float sigma = max(float(sampleRadius) * 0.5, 0.5);
 		float weight = exp(-distanceSquared / (2.0 * sigma * sigma));
-			float2 offset = float2(float(x), float(y)) * sampleStep;
+		float2 offset = float(x) * sampleStep;
 		blur += sampleVideo(context.uv + offset) * weight;
 		totalWeight += weight;
 	}
-	}
 
 	if (sampleRadius == 0)
 	{
@@ -29,7 +26,20 @@ float4 shadeVideo(ShaderContext context)
 	}
 
 	blur /= max(totalWeight, 0.0001);
-
-	float mixValue = saturate(strength);
-	return lerp(center, blur, mixValue);
+	return blur;
+}
+
+float4 blurHorizontal(ShaderContext context)
+{
+	return gaussianBlurDirection(context, float2(1.0, 0.0));
+}
+
+float4 blurVertical(ShaderContext context)
+{
+	return gaussianBlurDirection(context, float2(0.0, 1.0));
+}
+
+float4 shadeVideo(ShaderContext context)
+{
+	return blurVertical(context);
 }

shaders/multipass-test/shader.json

@@ -0,0 +1,43 @@
+{
+  "id": "multipass-test",
+  "name": "Multipass Test",
+  "description": "Diagnostic two-pass shader that generates a mask in pass one, then samples that named intermediate in pass two.",
+  "category": "Utility",
+  "entryPoint": "shadeVideo",
+  "passes": [
+    {
+      "id": "mask",
+      "source": "shader.slang",
+      "entryPoint": "buildMask",
+      "inputs": ["layerInput"],
+      "output": "generatedMask"
+    },
+    {
+      "id": "final",
+      "source": "shader.slang",
+      "entryPoint": "applyMask",
+      "inputs": ["generatedMask"],
+      "output": "layerOutput"
+    }
+  ],
+  "parameters": [
+    {
+      "id": "intensity",
+      "label": "Intensity",
+      "type": "float",
+      "default": 1.0,
+      "min": 0.0,
+      "max": 1.0,
+      "step": 0.01
+    },
+    {
+      "id": "scale",
+      "label": "Scale",
+      "type": "float",
+      "default": 10.0,
+      "min": 2.0,
+      "max": 32.0,
+      "step": 1.0
+    }
+  ]
+}

shaders/multipass-test/shader.slang

@@ -0,0 +1,38 @@
+float ringMask(float2 uv)
+{
+	float2 centered = uv * 2.0 - 1.0;
+	float radius = length(centered);
+	float ring = 1.0 - smoothstep(0.015, 0.035, abs(radius - 0.55));
+	float cross = 1.0 - smoothstep(0.006, 0.018, min(abs(centered.x), abs(centered.y)));
+	return saturate(max(ring, cross));
+}
+
+float gridMask(float2 uv)
+{
+	float2 cell = abs(frac(uv * max(scale, 1.0)) - 0.5);
+	float line = 1.0 - smoothstep(0.455, 0.495, max(cell.x, cell.y));
+	return saturate(line * 0.55);
+}
+
+float4 buildMask(ShaderContext context)
+{
+	float mask = saturate(max(ringMask(context.uv), gridMask(context.uv)));
+	return float4(mask, context.uv.x, context.uv.y, 1.0);
+}
+
+float4 applyMask(ShaderContext context)
+{
+	float4 generated = sampleVideo(context.uv);
+	float mask = generated.r;
+	float2 encodedUv = generated.gb;
+	float checker = step(0.5, frac((encodedUv.x + encodedUv.y) * max(scale, 1.0)));
+	float3 testColor = lerp(float3(0.0, 0.75, 1.0), float3(1.0, 0.1, 0.85), checker);
+	float3 base = context.sourceColor.rgb * 0.35;
+	float3 color = lerp(base, testColor, mask * saturate(intensity));
+	return float4(color, context.sourceColor.a);
+}
+
+float4 shadeVideo(ShaderContext context)
+{
+	return applyMask(context);
+}