Handle TooManyAttachments in wgpu-core (#6076)

Author: sagudev

wgpu-core/src/command/mod.rs

@@ -595,6 +595,8 @@ pub enum CommandEncoderError {
     InvalidTimestampWritesQuerySetId(id::QuerySetId),
     #[error("Attachment TextureViewId {0:?} is invalid")]
     InvalidAttachmentId(id::TextureViewId),
+    #[error(transparent)]
+    InvalidColorAttachment(#[from] ColorAttachmentError),
     #[error("Resolve attachment TextureViewId {0:?} is invalid")]
     InvalidResolveTargetId(id::TextureViewId),
     #[error("Depth stencil attachment TextureViewId {0:?} is invalid")]

wgpu-core/src/command/render.rs

@@ -1342,10 +1342,21 @@ impl Global {
             hub: &crate::hub::Hub<A>,
             desc: &RenderPassDescriptor<'_>,
             arc_desc: &mut ArcRenderPassDescriptor<A>,
+            device: &Device<A>,
         ) -> Result<(), CommandEncoderError> {
             let query_sets = hub.query_sets.read();
             let texture_views = hub.texture_views.read();
 
+            let max_color_attachments = device.limits.max_color_attachments as usize;
+            if desc.color_attachments.len() > max_color_attachments {
+                return Err(CommandEncoderError::InvalidColorAttachment(
+                    ColorAttachmentError::TooMany {
+                        given: desc.color_attachments.len(),
+                        limit: max_color_attachments,
+                    },
+                ));
+            }
+
             for color_attachment in desc.color_attachments.iter() {
                 if let Some(RenderPassColorAttachment {
                     view: view_id,
@@ -1447,7 +1458,7 @@ impl Global {
             Err(e) => return make_err(e, arc_desc),
         };
 
-        let err = fill_arc_desc(hub, desc, &mut arc_desc).err();
+        let err = fill_arc_desc(hub, desc, &mut arc_desc, &cmd_buf.device).err();
 
         (RenderPass::new(Some(cmd_buf), arc_desc), err)
     }

wgpu/src/backend/wgpu_core.rs

@@ -1923,15 +1923,6 @@ impl crate::Context for ContextWgpuCore {
         encoder_data: &Self::CommandEncoderData,
         desc: &crate::RenderPassDescriptor<'_>,
     ) -> (Self::RenderPassId, Self::RenderPassData) {
-        if desc.color_attachments.len() > wgc::MAX_COLOR_ATTACHMENTS {
-            self.handle_error_fatal(
-                wgc::command::ColorAttachmentError::TooMany {
-                    given: desc.color_attachments.len(),
-                    limit: wgc::MAX_COLOR_ATTACHMENTS,
-                },
-                "CommandEncoder::begin_render_pass",
-            );
-        }
         let colors = desc
             .color_attachments
             .iter()
@@ -1943,7 +1934,7 @@ impl crate::Context for ContextWgpuCore {
                         channel: map_pass_channel(Some(&at.ops)),
                     })
             })
-            .collect::<ArrayVec<_, { wgc::MAX_COLOR_ATTACHMENTS }>>();
+            .collect::<Vec<_>>();
 
         let depth_stencil = desc.depth_stencil_attachment.as_ref().map(|dsa| {
             wgc::command::RenderPassDepthStencilAttachment {