fixup! [naga hlsl-out] Implement external texture support

Author: jamienicol

naga/src/back/hlsl/help.rs

@@ -294,7 +294,7 @@ impl<W: Write> super::Writer<'_, W> {
                 // If params.size is zero then clamp to the actual size of the texture.
                 writeln!(
                     self.out,
-                    "{l1}uint2 cropped_size = params.size != 0 ? params.size : plane0_size;"
+                    "{l1}uint2 cropped_size = any(params.size) ? params.size : plane0_size;"
                 )?;
                 writeln!(self.out, "{l1}coords = min(coords, cropped_size - 1);")?;
 
@@ -342,7 +342,7 @@ impl<W: Write> super::Writer<'_, W> {
                     self.out,
                     "{l3}plane2.GetDimensions(plane2_size.x, plane2_size.y);"
                 )?;
-                writeln!(self.out, "{l2}uint2 plane2_coords = uint2(floor(float2(plane0_coords) * float2(plane2_size) / float2(plane0_size)));")?;
+                writeln!(self.out, "{l3}uint2 plane2_coords = uint2(floor(float2(plane0_coords) * float2(plane2_size) / float2(plane0_size)));")?;
                 writeln!(self.out, "{l3}uv = float2(plane1.Load(uint3(plane1_coords, 0u)).x, plane2.Load(uint3(plane2_coords, 0u)).x);")?;
                 writeln!(self.out, "{l2}}}")?;
 
@@ -405,10 +405,13 @@ impl<W: Write> super::Writer<'_, W> {
                     self.out,
                     "{l1}coords = mul(float3(coords, 1.0), sample_transform);"
                 )?;
-                // Calculate the sample bounds taking in to account the transform,
-                // bearing in mind that it may contain a flip on either axis. We must
-                // calculate and adjust for the half-texel separately for each plane as
-                // it depends on the texture size which may vary between planes.
+                // Calculate the sample bounds. The purported size of the texture
+                // (params.size) is irrelevant here as we are dealing with normalized
+                // coordinates. Usually we would clamp to (0,0)..(1,1). However, we must
+                // apply the sample transformation to that, also bearing in mind that it
+                // may contain a flip on either axis. We calculate and adjust for the
+                // half-texel separately for each plane as it depends on the actual
+                // texture size which may vary between planes.
                 writeln!(
                     self.out,
                     "{l1}float2 bounds_min = mul(float3(0.0, 0.0, 1.0), sample_transform);"

naga/tests/out/hlsl/wgsl-texture-external.hlsl

@@ -68,7 +68,7 @@ float4 nagaTextureLoadExternal(
 {
     uint2 plane0_size;
     plane0.GetDimensions(plane0_size.x, plane0_size.y);
-    uint2 cropped_size = params.size != 0 ? params.size : plane0_size;
+    uint2 cropped_size = any(params.size) ? params.size : plane0_size;
     coords = min(coords, cropped_size - 1);
     float3x2 load_transform = float3x2(
         params.load_transform_0,
@@ -89,7 +89,7 @@ float4 nagaTextureLoadExternal(
         } else {
             uint2 plane2_size;
             plane2.GetDimensions(plane2_size.x, plane2_size.y);
-        uint2 plane2_coords = uint2(floor(float2(plane0_coords) * float2(plane2_size) / float2(plane0_size)));
+            uint2 plane2_coords = uint2(floor(float2(plane0_coords) * float2(plane2_size) / float2(plane0_size)));
             uv = float2(plane1.Load(uint3(plane1_coords, 0u)).x, plane2.Load(uint3(plane2_coords, 0u)).x);
         }
         return mul(float4(y, uv, 1.0), params.yuv_conversion_matrix);