yet another workaround for https://github.com/gfx-rs/naga/issues/1743

crates/re_renderer/shader/point_cloud.wgsl

@@ -111,6 +111,20 @@ fn vs_main(@builtin(vertex_index) vertex_idx: u32) -> VertexOut {
     return out;
 }
 
+// TODO(andreas): move this to sphere_quad.wgsl once https://github.com/gfx-rs/naga/issues/1743 is resolved
+// point_cloud.rs has a specific workaround in place so we don't need to split vertex/fragment shader here
+//
+/// Computes coverage of a 2D sphere placed at `circle_center` in the fragment shader using the currently set camera.
+///
+/// 2D primitives are always facing the camera - the difference to sphere_quad_coverage is that
+/// perspective projection is not taken into account.
+fn circle_quad_coverage(world_position: Vec3, radius: f32, circle_center: Vec3) -> f32 {
+    let to_center = circle_center - world_position;
+    let distance = length(to_center);
+    let distance_pixel_difference = fwidth(distance);
+    return smoothstep(radius + distance_pixel_difference, radius - distance_pixel_difference, distance);
+}
+
 fn coverage(world_position: Vec3, radius: f32, point_center: Vec3) -> f32 {
     if is_camera_orthographic() || has_any_flag(batch.flags, DRAW_AS_CIRCLES) {
         return circle_quad_coverage(world_position, radius, point_center);

crates/re_renderer/shader/utils/sphere_quad.wgsl

@@ -111,14 +111,3 @@ fn sphere_quad_coverage(world_position: Vec3, radius: f32, sphere_center: Vec3)
     // Note that we have signed distances to the sphere surface.
     return saturate(0.5 - distance_to_surface_in_pixels);
 }
-
-/// Computes coverage of a 2D sphere placed at `circle_center` in the fragment shader using the currently set camera.
-///
-/// 2D primitives are always facing the camera - the difference to sphere_quad_coverage is that
-/// perspective projection is not taken into account.
-fn circle_quad_coverage(world_position: Vec3, radius: f32, circle_center: Vec3) -> f32 {
-    let to_center = circle_center - world_position;
-    let distance = length(to_center);
-    let distance_pixel_difference = fwidth(distance);
-    return smoothstep(radius + distance_pixel_difference, radius - distance_pixel_difference, distance);
-}

crates/re_renderer/src/renderer/point_cloud.rs

@@ -624,17 +624,26 @@ impl Renderer for PointCloudRenderer {
             &pools.bind_group_layouts,
         );
 
-        let shader_module = pools.shader_modules.get_or_create(
-            device,
-            resolver,
-            &include_shader_module!("../../shader/point_cloud.wgsl"),
-        );
+        let shader_module_desc = include_shader_module!("../../shader/point_cloud.wgsl");
+        let shader_module =
+            pools
+                .shader_modules
+                .get_or_create(device, resolver, &shader_module_desc);
+
+        // HACK/WORKAROUND for https://github.com/gfx-rs/naga/issues/1743
+        let mut shader_module_desc_vertex = shader_module_desc.clone();
+        shader_module_desc_vertex.extra_workaround_replacements =
+            vec![("fwidth(".to_owned(), "f32(".to_owned())];
+        let shader_module_vertex =
+            pools
+                .shader_modules
+                .get_or_create(device, resolver, &shader_module_desc_vertex);
 
         let render_pipeline_desc_color = RenderPipelineDesc {
             label: "PointCloudRenderer::render_pipeline_color".into(),
             pipeline_layout,
             vertex_entrypoint: "vs_main".into(),
-            vertex_handle: shader_module,
+            vertex_handle: shader_module_vertex,
             fragment_entrypoint: "fs_main".into(),
             fragment_handle: shader_module,
             vertex_buffers: smallvec![],

crates/re_renderer/src/wgpu_resources/shader_module_pool.rs

@@ -21,6 +21,7 @@ macro_rules! include_shader_module {
         $crate::wgpu_resources::ShaderModuleDesc {
             label: $crate::DebugLabel::from(stringify!($path).strip_prefix("../../shader/")),
             source: $crate::include_file!($path),
+            extra_workaround_replacements: Vec::new(),
         }
     }};
 }
@@ -33,6 +34,9 @@ pub struct ShaderModuleDesc {
 
     /// Path to the source code of this shader module.
     pub source: PathBuf,
+
+    /// Additional text replacement workarounds that may be added on top of globally known workarounds.
+    pub extra_workaround_replacements: Vec<(String, String)>,
 }
 
 impl PartialEq for ShaderModuleDesc {
@@ -46,6 +50,7 @@ impl Hash for ShaderModuleDesc {
         // NOTE: for a shader, the only thing that should matter is the source
         // code since we can have many entrypoints referring to the same file!
         self.source.hash(state);
+        self.extra_workaround_replacements.hash(state);
     }
 }
 
@@ -62,7 +67,10 @@ impl ShaderModuleDesc {
             .map_err(|err| re_log::error!(err=%re_error::format(err)))
             .unwrap_or_default();
 
-        for (from, to) in shader_text_workaround_replacements {
+        for (from, to) in shader_text_workaround_replacements
+            .iter()
+            .chain(self.extra_workaround_replacements.iter())
+        {
             source_interpolated.contents = source_interpolated.contents.replace(from, to);
         }
 

crates/re_web_viewer_server/build.rs

@@ -57,6 +57,7 @@ impl<'a> Packages<'a> {
             // account for locally patched dependencies.
             rerun_if_changed(path.join("Cargo.toml").as_ref());
             rerun_if_changed(path.join("**/*.rs").as_ref());
+            rerun_if_changed(path.join("**/*.wgsl").as_ref());
         }
 
         // Track all direct and indirect dependencies of that root package