Fix WebGPU error when sampling depth texture in shader which requires explicit UnfilterableFloat sampler type

Source/Shaders/Common.hlsl

@@ -136,6 +136,18 @@ SamplerComparisonState ShadowSamplerLinear : register(s5);
 // General purpose macros
 #define SAMPLE_RT(rt, texCoord) rt.SampleLevel(SamplerPointClamp, texCoord, 0)
 #define SAMPLE_RT_LINEAR(rt, texCoord) rt.SampleLevel(SamplerLinearClamp, texCoord, 0)
+#if defined(WGSL)
+// WebGPU doesn't allow to sample depth texture with regular sampler, need to use Load instead of Sample and get texture size for UV to pixel coordinate conversion
+float4 LoadTextureWGSL(Texture2D tex, float2 uv)
+{
+    uint2 size;
+    tex.GetDimensions(size.x, size.y);
+    return tex.Load(uint3(size * uv, 0));
+}
+#define SAMPLE_RT_LOAD(rt, texCoord) LoadTextureWGSL(rt, texCoord)
+#else
+#define SAMPLE_RT_LOAD(rt, texCoord) SAMPLE_RT(rt, texCoord)
+#endif
 #define HDR_CLAMP_MAX 65472.0
 #define PI 3.1415926535897932
 

Source/Shaders/Fog.shader

@@ -34,7 +34,7 @@ META_PERMUTATION_1(VOLUMETRIC_FOG=1)
 float4 PS_Fog(Quad_VS2PS input) : SV_Target0
 {
     // Get world space position at given pixel coordinate
-	float rawDepth = SAMPLE_RT(Depth, input.TexCoord).r;
+	float rawDepth = SAMPLE_RT_LOAD(Depth, input.TexCoord).r;
 	GBufferData gBufferData = GetGBufferData();
 	float3 viewPos = GetViewPos(gBufferData, input.TexCoord, rawDepth);
 	float3 worldPos = mul(float4(viewPos, 1), gBufferData.InvViewMatrix).xyz;

Source/Shaders/GBuffer.hlsl

@@ -56,7 +56,7 @@ float3 GetWorldPos(GBufferData gBuffer, float2 uv, float deviceDepth)
 // Sample raw device depth buffer
 float SampleZ(float2 uv)
 {
-    return SAMPLE_RT(Depth, uv).r;
+    return SAMPLE_RT_LOAD(Depth, uv).r;
 }
 
 // Sample linear depth
@@ -125,25 +125,6 @@ GBufferSample SampleGBuffer(GBufferData gBuffer, float2 uv)
     return result;
 }
 
-// Sample GBuffer (fast - only few parameters are being sampled)
-GBufferSample SampleGBufferFast(GBufferData gBuffer, float2 uv)
-{
-    GBufferSample result;
-
-    // Sample GBuffer
-    float4 gBuffer1 = SAMPLE_RT(GBuffer1, uv);
-
-    // Decode normal and shading model
-    result.Normal = DecodeNormal(gBuffer1.rgb);
-    result.ShadingModel = (int)(gBuffer1.a * 3.999);
-
-    // Calculate view space position
-    result.ViewPos = GetViewPos(gBuffer, uv);
-    result.WorldPos = mul(float4(result.ViewPos, 1), gBuffer.InvViewMatrix).xyz;
-
-    return result;
-}
-
 #if defined(USE_GBUFFER_CUSTOM_DATA)
 
 // Sample GBuffer custom data only

Source/Shaders/MotionBlur.shader

@@ -204,7 +204,7 @@ float4 PS_MotionBlur(Quad_VS2PS input) : SV_Target
 
 	// Sample pixel depth
 	GBufferData gBufferData = GetGBufferData();
-	float pixelDepth = LinearizeZ(gBufferData, SAMPLE_RT(Input3, input.TexCoord).x);
+	float pixelDepth = LinearizeZ(gBufferData, SAMPLE_RT_LOAD(Input3, input.TexCoord).x);
 
 	// Calculate noise to make it look better with less samples per pixel
 	float noise = FullscreenGradientNoise(input.TexCoord);
@@ -229,12 +229,12 @@ float4 PS_MotionBlur(Quad_VS2PS input) : SV_Target
 		float weight1 = 1;
 		float weight2 = 1;
 #else
-		float depth1 = LinearizeZ(gBufferData, SAMPLE_RT(Input3, sampleUV1).x);
+		float depth1 = LinearizeZ(gBufferData, SAMPLE_RT_LOAD(Input3, sampleUV1).x);
 		float2 velocity1 = Input1.SampleLevel(SamplerPointClamp, sampleUV1, 0).xy;
 		velocity1 = ClampVelocity(velocity1);
 		float velocityLength1 = length(velocity1);
 
-		float depth2 = LinearizeZ(gBufferData, SAMPLE_RT(Input3, sampleUV2).x);
+		float depth2 = LinearizeZ(gBufferData, SAMPLE_RT_LOAD(Input3, sampleUV2).x);
 		float2 velocity2 = Input1.SampleLevel(SamplerPointClamp, sampleUV2, 0).xy;
 		velocity2 = ClampVelocity(velocity2);
 		float velocityLength2 = length(velocity2);

Source/Shaders/SSR.hlsl

@@ -116,7 +116,7 @@ float3 TraceScreenSpaceReflection(
     while (currSampleIndex < numSamples)
     {
         // Sample depth buffer and calculate depth difference
-        float currSample = SAMPLE_RT(depthBuffer, currOffset.xy).r;
+        float currSample = SAMPLE_RT_LOAD(depthBuffer, currOffset.xy).r;
         float depthDiff = currOffset.z - currSample;
 
         // Check intersection

Source/Shaders/TAA.shader

@@ -35,7 +35,7 @@ float4 PS(Quad_VS2PS input) : SV_Target0
 	float2 velocity = SAMPLE_RT_LINEAR(MotionVectors, input.TexCoord).xy;
 	float velocityLength = length(velocity);
 	float2 prevUV = input.TexCoord - velocity;
-	float prevDepth = LinearizeZ(GBuffer, SAMPLE_RT(Depth, prevUV).r);
+	float prevDepth = LinearizeZ(GBuffer, SAMPLE_RT_LOAD(Depth, prevUV).r);
 
 	// Find the closest pixel in 3x3 neighborhood
 	float currentDepth = 1;
@@ -55,7 +55,7 @@ float4 PS(Quad_VS2PS input) : SV_Target0
 			neighborhoodMax = max(neighborhoodMax, neighbor);
 			neighborhoodSum += neighbor;
 
-			float neighborDepth = LinearizeZ(GBuffer, SAMPLE_RT(Depth, sampleUV).r);
+			float neighborDepth = LinearizeZ(GBuffer, SAMPLE_RT_LOAD(Depth, sampleUV).r);
 			float depthDiff = abs(max(neighborDepth - prevDepth, 0));
 			minDepthDiff = min(minDepthDiff, depthDiff);
 			if (x == 0 && y == 0)