Add multiview limits and tests (#8206)

Co-authored-by: Andreas Reich <r_andreas2@web.de>
Co-authored-by: Magnus <85136135+SupaMaggie70Incorporated@users.noreply.github.com>

CHANGELOG.md

@@ -40,7 +40,7 @@ Bottom level categories:
 
 ## Unreleased
 
-### Major changes
+### Major Changes
 
 #### `wgpu::Instance::enumerate_adapters` is now `async` & available on WebGPU
 
@@ -73,6 +73,38 @@ SamplerDescriptor {
 }
 ```
 
+#### Multiview on all major platforms and support for multiview bitmasks
+
+Multiview is a feature that allows rendering the same content to multiple layers of a texture. This is useful primarily in VR where you wish to
+display almost identical content to 2 views, just with a different perspective. Instead of using 2 draw calls or 2 instances for each object, you
+can use this feature.
+
+Multiview is also called view instancing in DX12 land or vertex amplification in Metal land.
+
+Multiview has been reworked, adding support for Metal, and adding testing and validation to wgpu itself.
+This change also introduces a view bitmask, a new field in `RenderPassDescriptor` that allows a render pass to render to multiple non-adjacent layers
+when using the `SELECTIVE_MULTIVIEW` feature. Note that this also influences apps that don't use multiview, as they have to set this mask to `None`.
+```diff
+- wgpu::RenderPassDescriptor {
+-     label: None,
+-     color_attachments: &color_attachments,
+-     depth_stencil_attachment: None,
+-     timestamp_writes: None,
+-     occlusion_query_set: None,
+- }
++ wgpu::RenderPassDescriptor {
++     label: None,
++     color_attachments: &color_attachments,
++     depth_stencil_attachment: None,
++     timestamp_writes: None,
++     occlusion_query_set: None,
++     multiview_mask: NonZero::new(3),
++ }
+```
+One other breaking change worth noting is that in WGSL `@builtin(view_index)` now requires a type of `u32`, where previously it required `i32`.
+
+By @SupaMaggie70Incorporated in [#8206](https://github.com/gfx-rs/wgpu/pull/8206).
+
 ### New Features
 
 - Added support for transient textures on Vulkan and Metal. By @opstic in [#8247](https://github.com/gfx-rs/wgpu/pull/8247)

benches/benches/wgpu-benchmark/renderpass.rs

@@ -224,7 +224,7 @@ impl RenderpassState {
                         })],
                         compilation_options: wgpu::PipelineCompilationOptions::default(),
                     }),
-                    multiview: None,
+                    multiview_mask: None,
                     cache: None,
                 });
 
@@ -322,7 +322,7 @@ impl RenderpassState {
                         })],
                         compilation_options: wgpu::PipelineCompilationOptions::default(),
                     }),
-                    multiview: None,
+                    multiview_mask: None,
                     cache: None,
                 },
             ));
@@ -370,6 +370,7 @@ impl RenderpassState {
             occlusion_query_set: None,
             timestamp_writes: None,
             depth_stencil_attachment: None,
+            multiview_mask: None,
         });
 
         let start_idx = pass_number * draws_per_pass;
@@ -417,6 +418,7 @@ impl RenderpassState {
             occlusion_query_set: None,
             timestamp_writes: None,
             depth_stencil_attachment: None,
+            multiview_mask: None,
         });
 
         render_pass.set_pipeline(self.bindless_pipeline.as_ref().unwrap());

deno_webgpu/command_encoder.rs

@@ -2,6 +2,7 @@
 
 use std::borrow::Cow;
 use std::cell::RefCell;
+use std::num::NonZero;
 
 use deno_core::cppgc::Ptr;
 use deno_core::op2;
@@ -142,6 +143,7 @@ impl GPUCommandEncoder {
       occlusion_query_set: descriptor
         .occlusion_query_set
         .map(|query_set| query_set.id),
+      multiview_mask: NonZero::new(descriptor.multiview_mask),
     };
 
     let (render_pass, err) = self

deno_webgpu/device.rs

@@ -876,7 +876,7 @@ impl GPUDevice {
       multisample,
       fragment,
       cache: None,
-      multiview: None,
+      multiview_mask: None,
     };
 
     let (id, err) = self.instance.device_create_render_pipeline(

deno_webgpu/render_pass.rs

@@ -460,6 +460,9 @@ pub(crate) struct GPURenderPassDescriptor {
   /*#[webidl(default = 50000000)]
   #[options(enforce_range = true)]
   pub max_draw_count: u64,*/
+  #[webidl(default = 0)]
+  #[options(enforce_range = true)]
+  pub multiview_mask: u32,
 }
 
 #[derive(WebIDL)]

examples/features/src/boids/mod.rs

@@ -148,7 +148,7 @@ impl crate::framework::Example for Example {
             primitive: wgpu::PrimitiveState::default(),
             depth_stencil: None,
             multisample: wgpu::MultisampleState::default(),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 
@@ -276,6 +276,7 @@ impl crate::framework::Example for Example {
             depth_stencil_attachment: None,
             timestamp_writes: None,
             occlusion_query_set: None,
+            multiview_mask: None,
         };
 
         // get command encoder

examples/features/src/bunnymark/mod.rs

@@ -122,6 +122,7 @@ impl Example {
                 depth_stencil_attachment: None,
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
             rpass.set_pipeline(&self.pipeline);
             rpass.set_bind_group(0, &self.global_group, &[]);
@@ -229,7 +230,7 @@ impl crate::framework::Example for Example {
             },
             depth_stencil: None,
             multisample: wgpu::MultisampleState::default(),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 

examples/features/src/conservative_raster/mod.rs

@@ -106,7 +106,7 @@ impl crate::framework::Example for Example {
                 },
                 depth_stencil: None,
                 multisample: wgpu::MultisampleState::default(),
-                multiview: None,
+                multiview_mask: None,
                 cache: None,
             });
 
@@ -129,7 +129,7 @@ impl crate::framework::Example for Example {
                 primitive: wgpu::PrimitiveState::default(),
                 depth_stencil: None,
                 multisample: wgpu::MultisampleState::default(),
-                multiview: None,
+                multiview_mask: None,
                 cache: None,
             });
 
@@ -160,7 +160,7 @@ impl crate::framework::Example for Example {
                     },
                     depth_stencil: None,
                     multisample: wgpu::MultisampleState::default(),
-                    multiview: None,
+                    multiview_mask: None,
                     cache: None,
                 }),
             )
@@ -217,7 +217,7 @@ impl crate::framework::Example for Example {
                     primitive: wgpu::PrimitiveState::default(),
                     depth_stencil: None,
                     multisample: wgpu::MultisampleState::default(),
-                    multiview: None,
+                    multiview_mask: None,
                     cache: None,
                 }),
                 bind_group_layout,
@@ -273,6 +273,7 @@ impl crate::framework::Example for Example {
                 depth_stencil_attachment: None,
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
 
             rpass.set_pipeline(&self.pipeline_triangle_conservative);
@@ -295,6 +296,7 @@ impl crate::framework::Example for Example {
                 depth_stencil_attachment: None,
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
 
             rpass.set_pipeline(&self.pipeline_upscale);

examples/features/src/cube/mod.rs

@@ -256,7 +256,7 @@ impl crate::framework::Example for Example {
             },
             depth_stencil: None,
             multisample: wgpu::MultisampleState::default(),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 
@@ -298,7 +298,7 @@ impl crate::framework::Example for Example {
                 },
                 depth_stencil: None,
                 multisample: wgpu::MultisampleState::default(),
-                multiview: None,
+                multiview_mask: None,
                 cache: None,
             });
             Some(pipeline_wire)
@@ -356,6 +356,7 @@ impl crate::framework::Example for Example {
                 depth_stencil_attachment: None,
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
             rpass.push_debug_group("Prepare data for draw.");
             rpass.set_pipeline(&self.pipeline);

examples/features/src/hello_triangle/mod.rs

@@ -71,7 +71,7 @@ async fn run(event_loop: EventLoop<()>, window: Window) {
         primitive: wgpu::PrimitiveState::default(),
         depth_stencil: None,
         multisample: wgpu::MultisampleState::default(),
-        multiview: None,
+        multiview_mask: None,
         cache: None,
     });
 
@@ -129,6 +129,7 @@ async fn run(event_loop: EventLoop<()>, window: Window) {
                                     depth_stencil_attachment: None,
                                     timestamp_writes: None,
                                     occlusion_query_set: None,
+                                    multiview_mask: None,
                                 });
                             rpass.set_pipeline(&render_pipeline);
                             rpass.draw(0..3, 0..1);

examples/features/src/hello_windows/mod.rs

@@ -133,6 +133,7 @@ async fn run(event_loop: EventLoop<()>, viewports: Vec<(Arc<Window>, wgpu::Color
                                         depth_stencil_attachment: None,
                                         timestamp_writes: None,
                                         occlusion_query_set: None,
+                                        multiview_mask: None,
                                     });
                             }
 

examples/features/src/lib.rs

@@ -17,6 +17,7 @@ pub mod mesh_shader;
 pub mod mipmap;
 pub mod msaa_line;
 pub mod multiple_render_targets;
+pub mod multiview;
 pub mod ray_cube_compute;
 pub mod ray_cube_fragment;
 pub mod ray_cube_normals;

examples/features/src/main.rs

@@ -188,6 +188,12 @@ const EXAMPLES: &[ExampleDesc] = &[
         webgl: false,
         webgpu: false,
     },
+    ExampleDesc {
+        name: "multiview",
+        function: wgpu_examples::multiview::main,
+        webgl: false,
+        webgpu: false,
+    },
 ];
 
 fn get_example_name() -> Option<String> {

examples/features/src/mesh_shader/mod.rs

@@ -144,6 +144,7 @@ impl crate::framework::Example for Example {
                 depth_stencil_attachment: None,
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
             rpass.push_debug_group("Prepare data for draw.");
             rpass.set_pipeline(&self.pipeline);

examples/features/src/mipmap/mod.rs

@@ -104,7 +104,7 @@ impl Example {
             },
             depth_stencil: None,
             multisample: wgpu::MultisampleState::default(),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 
@@ -170,6 +170,7 @@ impl Example {
                 depth_stencil_attachment: None,
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
             if let Some(ref query_sets) = query_sets {
                 rpass.write_timestamp(&query_sets.timestamp, timestamp_query_index_base);
@@ -305,7 +306,7 @@ impl crate::framework::Example for Example {
             },
             depth_stencil: None,
             multisample: wgpu::MultisampleState::default(),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 
@@ -492,6 +493,7 @@ impl crate::framework::Example for Example {
                 depth_stencil_attachment: None,
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
             rpass.set_pipeline(&self.draw_pipeline);
             rpass.set_bind_group(0, &self.bind_group, &[]);

examples/features/src/msaa_line/mod.rs

@@ -77,7 +77,7 @@ impl Example {
                 count: sample_count,
                 ..Default::default()
             },
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
         let mut encoder =
@@ -307,6 +307,7 @@ impl crate::framework::Example for Example {
                     depth_stencil_attachment: None,
                     timestamp_writes: None,
                     occlusion_query_set: None,
+                    multiview_mask: None,
                 })
                 .execute_bundles(iter::once(&self.bundle));
         }

examples/features/src/multiple_render_targets/mod.rs

@@ -161,7 +161,7 @@ impl MultiTargetRenderer {
             primitive: wgpu::PrimitiveState::default(),
             depth_stencil: None,
             multisample: wgpu::MultisampleState::default(),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 
@@ -182,6 +182,7 @@ impl MultiTargetRenderer {
             depth_stencil_attachment: None,
             timestamp_writes: None,
             occlusion_query_set: None,
+            multiview_mask: None,
         });
         rpass.set_pipeline(&self.pipeline);
         rpass.set_bind_group(0, &self.bindgroup, &[]);
@@ -266,7 +267,7 @@ impl TargetRenderer {
             primitive: wgpu::PrimitiveState::default(),
             depth_stencil: None,
             multisample: wgpu::MultisampleState::default(),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 
@@ -339,6 +340,7 @@ impl TargetRenderer {
             depth_stencil_attachment: None,
             timestamp_writes: None,
             occlusion_query_set: None,
+            multiview_mask: None,
         });
         rpass.set_pipeline(&self.pipeline);
         rpass.set_bind_group(0, &self.bindgroup_left, &[]);

examples/features/src/multiview/mod.rs

@@ -0,0 +1,182 @@
+//! Renders different content to different layers of an array texture using multiview,
+//! a feature commonly used for VR rendering.
+
+use std::{num::NonZero, time::Instant};
+
+use wgpu::util::TextureBlitter;
+
+const TEXTURE_SIZE: u32 = 512;
+
+// Change this to demonstrate non-contiguous multiview functionality
+const LAYER_MASK: u32 = 0b11;
+
+const NUM_LAYERS: u32 = 32 - LAYER_MASK.leading_zeros();
+
+pub struct Example {
+    pipeline: wgpu::RenderPipeline,
+    entire_texture_view: wgpu::TextureView,
+    views: Vec<wgpu::TextureView>,
+    start_time: Instant,
+    blitter: TextureBlitter,
+}
+
+impl crate::framework::Example for Example {
+    fn init(
+        config: &wgpu::SurfaceConfiguration,
+        _adapter: &wgpu::Adapter,
+        device: &wgpu::Device,
+        _queue: &wgpu::Queue,
+    ) -> Self {
+        let shader_src = include_str!("shader.wgsl");
+
+        let shader = device.create_shader_module(wgpu::ShaderModuleDescriptor {
+            label: None,
+            source: wgpu::ShaderSource::Wgsl(shader_src.into()),
+        });
+
+        let pipeline = device.create_render_pipeline(&wgpu::RenderPipelineDescriptor {
+            label: None,
+            vertex: wgpu::VertexState {
+                buffers: &[],
+                module: &shader,
+                entry_point: Some("vs_main"),
+                compilation_options: Default::default(),
+            },
+            primitive: wgpu::PrimitiveState::default(),
+            fragment: Some(wgpu::FragmentState {
+                module: &shader,
+                entry_point: Some("fs_main"),
+                compilation_options: Default::default(),
+                targets: &[Some(wgpu::ColorTargetState {
+                    format: wgpu::TextureFormat::Rgba8Unorm,
+                    blend: None,
+                    write_mask: wgpu::ColorWrites::ALL,
+                })],
+            }),
+            multiview_mask: NonZero::new(LAYER_MASK),
+            multisample: Default::default(),
+            layout: None,
+            depth_stencil: None,
+            cache: None,
+        });
+        let texture = device.create_texture(&wgpu::TextureDescriptor {
+            label: None,
+            size: wgpu::Extent3d {
+                width: TEXTURE_SIZE,
+                height: TEXTURE_SIZE,
+                depth_or_array_layers: NUM_LAYERS,
+            },
+            mip_level_count: 1,
+            sample_count: 1,
+            dimension: wgpu::TextureDimension::D2,
+            format: wgpu::TextureFormat::Rgba8Unorm,
+            usage: wgpu::TextureUsages::RENDER_ATTACHMENT
+                | wgpu::TextureUsages::COPY_SRC
+                | wgpu::TextureUsages::TEXTURE_BINDING,
+            view_formats: &[],
+        });
+        let entire_texture_view = texture.create_view(&wgpu::TextureViewDescriptor {
+            label: None,
+            format: Some(wgpu::TextureFormat::Rgba8Unorm),
+            dimension: Some(wgpu::TextureViewDimension::D2Array),
+            usage: Some(wgpu::TextureUsages::RENDER_ATTACHMENT),
+            aspect: wgpu::TextureAspect::All,
+            base_mip_level: 0,
+            mip_level_count: None,
+            base_array_layer: 0,
+            array_layer_count: Some(NUM_LAYERS),
+        });
+        let mut views = Vec::new();
+        for i in 0..NUM_LAYERS {
+            views.push(texture.create_view(&wgpu::TextureViewDescriptor {
+                label: None,
+                format: Some(wgpu::TextureFormat::Rgba8Unorm),
+                dimension: Some(wgpu::TextureViewDimension::D2),
+                usage: Some(wgpu::TextureUsages::TEXTURE_BINDING),
+                aspect: wgpu::TextureAspect::All,
+                base_mip_level: 0,
+                mip_level_count: None,
+                base_array_layer: i,
+                array_layer_count: Some(1),
+            }));
+        }
+        let blitter = wgpu::util::TextureBlitter::new(device, config.format);
+        Self {
+            pipeline,
+            entire_texture_view,
+            views,
+            blitter,
+            start_time: Instant::now(),
+        }
+    }
+
+    fn render(&mut self, view: &wgpu::TextureView, device: &wgpu::Device, queue: &wgpu::Queue) {
+        let mut encoder = device.create_command_encoder(&wgpu::CommandEncoderDescriptor::default());
+        {
+            let mut rpass = encoder.begin_render_pass(&wgpu::RenderPassDescriptor {
+                label: None,
+                color_attachments: &[Some(wgpu::RenderPassColorAttachment {
+                    view: &self.entire_texture_view,
+                    depth_slice: None,
+                    resolve_target: None,
+                    ops: wgpu::Operations {
+                        load: wgpu::LoadOp::Clear(wgpu::Color {
+                            r: 0.02,
+                            g: 0.02,
+                            b: 0.02,
+                            a: 1.0,
+                        }),
+                        store: wgpu::StoreOp::Store,
+                    },
+                })],
+                depth_stencil_attachment: None,
+                timestamp_writes: None,
+                occlusion_query_set: None,
+                multiview_mask: NonZero::new(LAYER_MASK),
+            });
+            rpass.set_pipeline(&self.pipeline);
+            rpass.draw(0..6, 0..1);
+        }
+
+        let layer = (Instant::now() - self.start_time).as_secs() % NUM_LAYERS as u64;
+        self.blitter
+            .copy(device, &mut encoder, &self.views[layer as usize], view);
+        queue.submit(Some(encoder.finish()));
+    }
+
+    fn required_downlevel_capabilities() -> wgpu::DownlevelCapabilities {
+        Default::default()
+    }
+
+    fn required_features() -> wgpu::Features {
+        wgpu::Features::MULTIVIEW
+            | if !(LAYER_MASK + 1).is_power_of_two() {
+                wgpu::Features::SELECTIVE_MULTIVIEW
+            } else {
+                wgpu::Features::empty()
+            }
+    }
+
+    fn required_limits() -> wgpu::Limits {
+        wgpu::Limits {
+            max_multiview_view_count: NUM_LAYERS,
+            ..Default::default()
+        }
+    }
+
+    fn resize(
+        &mut self,
+        _config: &wgpu::SurfaceConfiguration,
+        _device: &wgpu::Device,
+        _queue: &wgpu::Queue,
+    ) {
+        // empty
+    }
+    fn update(&mut self, _event: winit::event::WindowEvent) {
+        // empty
+    }
+}
+
+pub fn main() {
+    crate::framework::run::<Example>("multiview");
+}

examples/features/src/multiview/shader.wgsl

@@ -0,0 +1,11 @@
+const triangles = array<vec2f, 3>(vec2f(-1.0, -1.0), vec2f(3.0, -1.0), vec2f(-1.0, 3.0));
+
+@vertex
+fn vs_main(@builtin(vertex_index) vertex_index: u32) -> @builtin(position) vec4f {
+    return vec4f(triangles[vertex_index], 0.0, 1.0);
+}
+
+@fragment
+fn fs_main(@builtin(view_index) view_index: u32) -> @location(0) vec4f {
+    return vec4f(f32(view_index) * 0.25 + 0.125, 1.0 - f32(view_index) * 0.25, 1.0 - 0.5 * f32(view_index), 1.0);
+}

examples/features/src/ray_cube_compute/mod.rs

@@ -326,7 +326,7 @@ impl crate::framework::Example for Example {
             },
             depth_stencil: None,
             multisample: wgpu::MultisampleState::default(),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 
@@ -469,6 +469,7 @@ impl crate::framework::Example for Example {
                 depth_stencil_attachment: None,
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
 
             rpass.set_pipeline(&self.blit_pipeline);

examples/features/src/ray_cube_fragment/mod.rs

@@ -216,7 +216,7 @@ impl crate::framework::Example for Example {
             },
             depth_stencil: None,
             multisample: wgpu::MultisampleState::default(),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 
@@ -355,6 +355,7 @@ impl crate::framework::Example for Example {
                 depth_stencil_attachment: None,
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
 
             rpass.set_pipeline(&self.pipeline);

examples/features/src/ray_cube_normals/mod.rs

@@ -317,7 +317,7 @@ impl crate::framework::Example for Example {
             },
             depth_stencil: None,
             multisample: wgpu::MultisampleState::default(),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 
@@ -455,6 +455,7 @@ impl crate::framework::Example for Example {
                 depth_stencil_attachment: None,
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
 
             rpass.set_pipeline(&self.blit_pipeline);

examples/features/src/ray_scene/mod.rs

@@ -395,7 +395,7 @@ impl crate::framework::Example for Example {
             },
             depth_stencil: None,
             multisample: wgpu::MultisampleState::default(),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 
@@ -535,6 +535,7 @@ impl crate::framework::Example for Example {
                 depth_stencil_attachment: None,
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
 
             rpass.set_pipeline(&self.pipeline);

examples/features/src/ray_shadows/mod.rs

@@ -239,7 +239,7 @@ impl crate::framework::Example for Example {
             },
             depth_stencil: None,
             multisample: wgpu::MultisampleState::default(),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 
@@ -348,6 +348,7 @@ impl crate::framework::Example for Example {
                 depth_stencil_attachment: None,
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
 
             rpass.set_pipeline(&self.pipeline);

examples/features/src/ray_traced_triangle/mod.rs

@@ -309,7 +309,7 @@ impl crate::framework::Example for Example {
                     write_mask: Default::default(),
                 })],
             }),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 
@@ -414,6 +414,7 @@ impl crate::framework::Example for Example {
                 depth_stencil_attachment: None,
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
 
             rpass.set_pipeline(&self.blit_pipeline);

examples/features/src/render_to_texture/mod.rs

@@ -68,7 +68,7 @@ async fn run(_path: Option<String>) {
         primitive: wgpu::PrimitiveState::default(),
         depth_stencil: None,
         multisample: wgpu::MultisampleState::default(),
-        multiview: None,
+        multiview_mask: None,
         cache: None,
     });
 
@@ -95,6 +95,7 @@ async fn run(_path: Option<String>) {
             depth_stencil_attachment: None,
             occlusion_query_set: None,
             timestamp_writes: None,
+            multiview_mask: None,
         });
         render_pass.set_pipeline(&pipeline);
         render_pass.draw(0..3, 0..1);

examples/features/src/shadow/mod.rs

@@ -518,7 +518,7 @@ impl crate::framework::Example for Example {
                     },
                 }),
                 multisample: wgpu::MultisampleState::default(),
-                multiview: None,
+                multiview_mask: None,
                 cache: None,
             });
 
@@ -653,7 +653,7 @@ impl crate::framework::Example for Example {
                     bias: wgpu::DepthBiasState::default(),
                 }),
                 multisample: wgpu::MultisampleState::default(),
-                multiview: None,
+                multiview_mask: None,
                 cache: None,
             });
 
@@ -771,6 +771,7 @@ impl crate::framework::Example for Example {
                     }),
                     timestamp_writes: None,
                     occlusion_query_set: None,
+                    multiview_mask: None,
                 });
                 pass.set_pipeline(&self.shadow_pass.pipeline);
                 pass.set_bind_group(0, &self.shadow_pass.bind_group, &[]);
@@ -816,6 +817,7 @@ impl crate::framework::Example for Example {
                 }),
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
             pass.set_pipeline(&self.forward_pass.pipeline);
             pass.set_bind_group(0, &self.forward_pass.bind_group, &[]);

examples/features/src/skybox/mod.rs

@@ -218,7 +218,7 @@ impl crate::framework::Example for Example {
                 bias: wgpu::DepthBiasState::default(),
             }),
             multisample: wgpu::MultisampleState::default(),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
         let entity_pipeline = device.create_render_pipeline(&wgpu::RenderPipelineDescriptor {
@@ -252,7 +252,7 @@ impl crate::framework::Example for Example {
                 bias: wgpu::DepthBiasState::default(),
             }),
             multisample: wgpu::MultisampleState::default(),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 
@@ -444,6 +444,7 @@ impl crate::framework::Example for Example {
                 }),
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
 
             rpass.set_bind_group(0, &self.bind_group, &[]);

examples/features/src/srgb_blend/mod.rs

@@ -146,7 +146,7 @@ impl<const SRGB: bool> crate::framework::Example for Example<SRGB> {
             },
             depth_stencil: None,
             multisample: wgpu::MultisampleState::default(),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 
@@ -196,6 +196,7 @@ impl<const SRGB: bool> crate::framework::Example for Example<SRGB> {
                 depth_stencil_attachment: None,
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
             rpass.push_debug_group("Prepare data for draw.");
             rpass.set_pipeline(&self.pipeline);

examples/features/src/stencil_triangles/mod.rs

@@ -100,7 +100,7 @@ impl crate::framework::Example for Example {
                 bias: Default::default(),
             }),
             multisample: wgpu::MultisampleState::default(),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 
@@ -136,7 +136,7 @@ impl crate::framework::Example for Example {
                 bias: Default::default(),
             }),
             multisample: wgpu::MultisampleState::default(),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 
@@ -222,6 +222,7 @@ impl crate::framework::Example for Example {
                 }),
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
 
             rpass.set_stencil_reference(1);

examples/features/src/texture_arrays/mod.rs

@@ -358,7 +358,7 @@ impl crate::framework::Example for Example {
             },
             depth_stencil: None,
             multisample: wgpu::MultisampleState::default(),
-            multiview: None,
+            multiview_mask: None,
             cache: None
         });
 
@@ -402,6 +402,7 @@ impl crate::framework::Example for Example {
             depth_stencil_attachment: None,
             timestamp_writes: None,
             occlusion_query_set: None,
+            multiview_mask: None,
         });
 
         rpass.set_pipeline(&self.pipeline);

examples/features/src/timestamp_queries/mod.rs

@@ -358,7 +358,7 @@ fn render_pass(
         primitive: wgpu::PrimitiveState::default(),
         depth_stencil: None,
         multisample: wgpu::MultisampleState::default(),
-        multiview: None,
+        multiview_mask: None,
         cache: None,
     });
     let render_target = device.create_texture(&wgpu::TextureDescriptor {
@@ -395,6 +395,7 @@ fn render_pass(
             end_of_pass_write_index: Some(*next_unused_query + 1),
         }),
         occlusion_query_set: None,
+        multiview_mask: None,
     });
     *next_unused_query += 2;
 

examples/features/src/uniform_values/mod.rs

@@ -186,7 +186,7 @@ impl WgpuContext {
             primitive: wgpu::PrimitiveState::default(),
             depth_stencil: None,
             multisample: wgpu::MultisampleState::default(),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
         let surface_config = surface
@@ -319,6 +319,7 @@ async fn run(event_loop: EventLoop<()>, window: Arc<Window>) {
                                         depth_stencil_attachment: None,
                                         occlusion_query_set: None,
                                         timestamp_writes: None,
+                                        multiview_mask: None,
                                     });
                                 render_pass.set_pipeline(&wgpu_context_ref.pipeline);
                                 // (9)

examples/features/src/water/mod.rs

@@ -567,7 +567,7 @@ impl crate::framework::Example for Example {
             }),
             // No multisampling is used.
             multisample: wgpu::MultisampleState::default(),
-            multiview: None,
+            multiview_mask: None,
             // No pipeline caching is used
             cache: None,
         });
@@ -605,7 +605,7 @@ impl crate::framework::Example for Example {
                 bias: wgpu::DepthBiasState::default(),
             }),
             multisample: wgpu::MultisampleState::default(),
-            multiview: None,
+            multiview_mask: None,
             cache: None
         });
 
@@ -750,6 +750,7 @@ impl crate::framework::Example for Example {
                 }),
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
 
             rpass.execute_bundles([&self.terrain_bundle]);
@@ -778,6 +779,7 @@ impl crate::framework::Example for Example {
                 }),
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
             rpass.set_pipeline(&self.terrain_pipeline);
             rpass.set_bind_group(0, &self.terrain_normal_bind_group, &[]);
@@ -805,6 +807,7 @@ impl crate::framework::Example for Example {
                 }),
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
 
             rpass.set_pipeline(&self.water_pipeline);

examples/standalone/02_hello_window/src/main.rs

@@ -107,6 +107,7 @@ impl State {
             depth_stencil_attachment: None,
             timestamp_writes: None,
             occlusion_query_set: None,
+            multiview_mask: None,
         });
 
         // If you wanted to call any drawing commands, they would go here.

naga/src/back/glsl/mod.rs

@@ -5215,8 +5215,13 @@ const fn glsl_built_in(built_in: crate::BuiltIn, options: VaryingOptions) -> &'s
                 "gl_FragCoord"
             }
         }
-        Bi::ViewIndex if options.targeting_webgl => "int(gl_ViewID_OVR)",
-        Bi::ViewIndex => "gl_ViewIndex",
+        Bi::ViewIndex => {
+            if options.targeting_webgl {
+                "gl_ViewID_OVR"
+            } else {
+                "uint(gl_ViewIndex)"
+            }
+        }
         // vertex
         Bi::BaseInstance => "uint(gl_BaseInstance)",
         Bi::BaseVertex => "uint(gl_BaseVertex)",

naga/src/back/hlsl/conv.rs

@@ -173,6 +173,7 @@ impl crate::BuiltIn {
             // to this field will get replaced with references to `SPECIAL_CBUF_VAR`
             // in `Writer::write_expr`.
             Self::NumWorkGroups => "SV_GroupID",
+            Self::ViewIndex => "SV_ViewID",
             // These builtins map to functions
             Self::SubgroupSize
             | Self::SubgroupInvocationId
@@ -181,7 +182,7 @@ impl crate::BuiltIn {
             Self::BaseInstance | Self::BaseVertex | Self::WorkGroupSize => {
                 return Err(Error::Unimplemented(format!("builtin {self:?}")))
             }
-            Self::PointSize | Self::ViewIndex | Self::PointCoord | Self::DrawID => {
+            Self::PointSize | Self::PointCoord | Self::DrawID => {
                 return Err(Error::Custom(format!("Unsupported builtin {self:?}")))
             }
             Self::CullPrimitive => "SV_CullPrimitive",

naga/src/back/hlsl/mod.rs

@@ -650,6 +650,8 @@ pub enum Error {
     ResolveArraySizeError(#[from] proc::ResolveArraySizeError),
     #[error("entry point with stage {0:?} and name '{1}' not found")]
     EntryPointNotFound(ir::ShaderStage, String),
+    #[error("requires shader model {1:?} for reason: {0}")]
+    ShaderModelTooLow(String, ShaderModel),
 }
 
 #[derive(PartialEq, Eq, Hash)]

naga/src/back/hlsl/writer.rs

@@ -569,6 +569,14 @@ impl<'a, W: fmt::Write> super::Writer<'a, W> {
     ) -> BackendResult {
         match *binding {
             Some(crate::Binding::BuiltIn(builtin)) if !is_subgroup_builtin_binding(binding) => {
+                if builtin == crate::BuiltIn::ViewIndex
+                    && self.options.shader_model < ShaderModel::V6_1
+                {
+                    return Err(Error::ShaderModelTooLow(
+                        "used @builtin(view_index) or SV_ViewID".to_string(),
+                        ShaderModel::V6_1,
+                    ));
+                }
                 let builtin_str = builtin.to_hlsl_str()?;
                 write!(self.out, " : {builtin_str}")?;
             }

naga/src/back/msl/mod.rs

@@ -530,6 +530,12 @@ impl Options {
                     crate::BuiltIn::PrimitiveIndex if self.lang_version < (2, 3) => {
                         return Err(Error::UnsupportedAttribute("primitive_id".to_string()));
                     }
+                    // macOS: since Metal 2.3
+                    // iOS: Since Metal 2.2
+                    // https://developer.apple.com/metal/Metal-Shading-Language-Specification.pdf#page=114
+                    crate::BuiltIn::ViewIndex if self.lang_version < (2, 2) => {
+                        return Err(Error::UnsupportedAttribute("amplification_id".to_string()));
+                    }
                     // macOS: Since Metal 2.2
                     // iOS: Since Metal 2.3 (check depends on https://github.com/gfx-rs/wgpu/issues/4414)
                     crate::BuiltIn::Barycentric if self.lang_version < (2, 3) => {
@@ -674,6 +680,7 @@ impl ResolvedBinding {
                 let name = match built_in {
                     Bi::Position { invariant: false } => "position",
                     Bi::Position { invariant: true } => "position, invariant",
+                    Bi::ViewIndex => "amplification_id",
                     // vertex
                     Bi::BaseInstance => "base_instance",
                     Bi::BaseVertex => "base_vertex",
@@ -701,7 +708,7 @@ impl ResolvedBinding {
                     Bi::SubgroupId => "simdgroup_index_in_threadgroup",
                     Bi::SubgroupSize => "threads_per_simdgroup",
                     Bi::SubgroupInvocationId => "thread_index_in_simdgroup",
-                    Bi::CullDistance | Bi::ViewIndex | Bi::DrawID => {
+                    Bi::CullDistance | Bi::DrawID => {
                         return Err(Error::UnsupportedBuiltIn(built_in))
                     }
                     Bi::CullPrimitive => "primitive_culled",

naga/src/valid/interface.rs

@@ -301,7 +301,7 @@ impl VaryingContext<'_> {
                             St::Vertex | St::Fragment | St::Task | St::Mesh => !self.output,
                             St::Compute => false,
                         },
-                        *ty_inner == Ti::Scalar(crate::Scalar::I32),
+                        *ty_inner == Ti::Scalar(crate::Scalar::U32),
                     ),
                     Bi::FragDepth => (
                         self.stage == St::Fragment && self.output,

naga/tests/in/wgsl/multiview.toml

@@ -1,3 +1,8 @@
 glsl_multiview = 2
 god_mode = true
-targets = "SPIRV | GLSL | WGSL"
+
+[msl]
+lang_version = [2, 3]
+
+[hlsl]
+shader_model = "V6_1"

naga/tests/in/wgsl/multiview.wgsl

@@ -1,2 +1,2 @@
 @fragment
-fn main(@builtin(view_index) view_index: i32) {}
+fn main(@builtin(view_index) view_index: u32) {}

naga/tests/in/wgsl/multiview_webgl.wgsl

@@ -1,2 +1,2 @@
 @fragment
-fn main(@builtin(view_index) view_index: i32) {}
+fn main(@builtin(view_index) view_index: u32) {}

naga/tests/out/glsl/wgsl-multiview.main.Fragment.glsl

@@ -6,7 +6,7 @@ precision highp int;
 
 
 void main() {
-    int view_index = gl_ViewIndex;
+    uint view_index = uint(gl_ViewIndex);
     return;
 }
 

naga/tests/out/glsl/wgsl-multiview_webgl.main.Fragment.glsl

@@ -6,7 +6,7 @@ precision highp int;
 
 
 void main() {
-    int view_index = int(gl_ViewID_OVR);
+    uint view_index = gl_ViewID_OVR;
     return;
 }
 

naga/tests/out/hlsl/wgsl-multiview.hlsl

@@ -0,0 +1,9 @@
+struct FragmentInput_main {
+    uint view_index_1 : SV_ViewID;
+};
+
+void main(FragmentInput_main fragmentinput_main)
+{
+    uint view_index = fragmentinput_main.view_index_1;
+    return;
+}

naga/tests/out/hlsl/wgsl-multiview.ron

@@ -0,0 +1,12 @@
+(
+    vertex:[
+    ],
+    fragment:[
+        (
+            entry_point:"main",
+            target_profile:"ps_6_1",
+        ),
+    ],
+    compute:[
+    ],
+)

naga/tests/out/msl/wgsl-multiview.msl

@@ -0,0 +1,14 @@
+// language: metal2.3
+#include <metal_stdlib>
+#include <simd/simd.h>
+
+using metal::uint;
+
+
+struct main_Input {
+};
+fragment void main_(
+  uint view_index [[amplification_id]]
+) {
+    return;
+}

naga/tests/out/spv/wgsl-multiview.spvasm

@@ -12,7 +12,7 @@ OpExecutionMode %8 OriginUpperLeft
 OpDecorate %5 BuiltIn ViewIndex
 OpDecorate %5 Flat
 %2 = OpTypeVoid
-%3 = OpTypeInt 32 1
+%3 = OpTypeInt 32 0
 %6 = OpTypePointer Input %3
 %5 = OpVariable  %6  Input
 %9 = OpTypeFunction %2

naga/tests/out/wgsl/wgsl-multiview.wgsl

@@ -1,4 +1,4 @@
 @fragment 
-fn main(@builtin(view_index) view_index: i32) {
+fn main(@builtin(view_index) view_index: u32) {
     return;
 }

player/src/lib.rs

@@ -674,7 +674,7 @@ impl Player {
             depth_stencil: desc.depth_stencil,
             multisample: desc.multisample,
             fragment,
-            multiview: desc.multiview,
+            multiview_mask: desc.multiview_mask,
             cache: desc.cache.map(|id| self.resolve_pipeline_cache_id(id)),
         }
     }
@@ -851,6 +851,7 @@ impl Player {
                 depth_stencil_attachment,
                 timestamp_writes,
                 occlusion_query_set,
+                multiview_mask,
             } => Command::RunRenderPass {
                 pass: self.resolve_render_pass(pass),
                 color_attachments: self.resolve_color_attachments(color_attachments),
@@ -858,6 +859,7 @@ impl Player {
                     .map(|att| self.resolve_depth_stencil_attachment(att)),
                 timestamp_writes: timestamp_writes.map(|tw| self.resolve_pass_timestamp_writes(tw)),
                 occlusion_query_set: occlusion_query_set.map(|qs| self.resolve_query_set_id(qs)),
+                multiview_mask,
             },
             Command::BuildAccelerationStructures { blas, tlas } => {
                 Command::BuildAccelerationStructures {

tests/tests/wgpu-gpu/binding_array/sampled_textures.rs

@@ -207,7 +207,7 @@ async fn binding_array_sampled_textures(ctx: TestingContext, partially_bound: bo
             depth_stencil: None,
             multisample: MultisampleState::default(),
             cache: None,
-            multiview: None,
+            multiview_mask: None,
         });
 
     let mut encoder = ctx
@@ -228,6 +228,7 @@ async fn binding_array_sampled_textures(ctx: TestingContext, partially_bound: bo
             depth_stencil_attachment: None,
             timestamp_writes: None,
             occlusion_query_set: None,
+            multiview_mask: None,
         });
         render_pass.set_pipeline(&pipeline);
         render_pass.set_bind_group(0, &bind_group, &[]);

tests/tests/wgpu-gpu/clip_distances.rs

@@ -43,7 +43,7 @@ async fn clip_distances(ctx: TestingContext) {
                     write_mask: wgpu::ColorWrites::ALL,
                 })],
             }),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 
@@ -87,6 +87,7 @@ async fn clip_distances(ctx: TestingContext) {
             depth_stencil_attachment: None,
             timestamp_writes: None,
             occlusion_query_set: None,
+            multiview_mask: None,
         });
         rpass.set_pipeline(&pipeline);
         rpass.draw(0..3, 0..1);

tests/tests/wgpu-gpu/device.rs

@@ -346,6 +346,7 @@ static DEVICE_DESTROY_THEN_MORE: GpuTestConfiguration = GpuTestConfiguration::ne
             depth_stencil_attachment: None,
             timestamp_writes: None,
             occlusion_query_set: None,
+            multiview_mask: None,
         });
         drop(pass);
         ctx.queue.submit([encoder_for_render_pass.finish()]);
@@ -458,7 +459,7 @@ static DEVICE_DESTROY_THEN_MORE: GpuTestConfiguration = GpuTestConfiguration::ne
                 depth_stencil: None,
                 multisample: wgpu::MultisampleState::default(),
                 fragment: None,
-                multiview: None,
+                multiview_mask: None,
                 cache: None,
             });
 
@@ -616,7 +617,7 @@ static DIFFERENT_BGL_ORDER_BW_SHADER_AND_API: GpuTestConfiguration = GpuTestConf
                 primitive: wgpu::PrimitiveState::default(),
                 depth_stencil: None,
                 multisample: wgpu::MultisampleState::default(),
-                multiview: None,
+                multiview_mask: None,
                 cache: None,
             });
 

tests/tests/wgpu-gpu/draw_indirect.rs

@@ -207,7 +207,7 @@ async fn run_test(ctx: TestingContext, test_data: TestData, expect_noop: bool) {
                 write_mask: wgpu::ColorWrites::ALL,
             })],
         }),
-        multiview: None,
+        multiview_mask: None,
         cache: None,
     };
     let pipeline = ctx.device.create_render_pipeline(&pipeline_desc);
@@ -272,6 +272,7 @@ async fn run_test(ctx: TestingContext, test_data: TestData, expect_noop: bool) {
             depth_stencil_attachment: None,
             timestamp_writes: None,
             occlusion_query_set: None,
+            multiview_mask: None,
         });
 
         rpass.set_pipeline(&pipeline);
@@ -697,7 +698,7 @@ async fn indirect_buffer_offsets(ctx: TestingContext) {
                 write_mask: wgpu::ColorWrites::ALL,
             })],
         }),
-        multiview: None,
+        multiview_mask: None,
         cache: None,
     };
     let pipeline = ctx.device.create_render_pipeline(&pipeline_desc);
@@ -747,6 +748,7 @@ async fn indirect_buffer_offsets(ctx: TestingContext) {
             depth_stencil_attachment: None,
             timestamp_writes: None,
             occlusion_query_set: None,
+            multiview_mask: None,
         });
 
         rpass.set_pipeline(&pipeline);

tests/tests/wgpu-gpu/dual_source_blending.rs

@@ -96,7 +96,7 @@ async fn dual_source_blending_disabled(ctx: TestingContext) {
                     primitive: wgpu::PrimitiveState::default(),
                     depth_stencil: None,
                     multisample: wgpu::MultisampleState::default(),
-                    multiview: None,
+                    multiview_mask: None,
                     cache: None,
                 });
         },
@@ -159,7 +159,7 @@ async fn dual_source_blending_enabled(ctx: TestingContext) {
         primitive: wgpu::PrimitiveState::default(),
         depth_stencil: None,
         multisample: wgpu::MultisampleState::default(),
-        multiview: None,
+        multiview_mask: None,
         cache: None,
     };
 

tests/tests/wgpu-gpu/encoder.rs

@@ -77,6 +77,7 @@ static DROP_ENCODER_AFTER_ERROR: GpuTestConfiguration = GpuTestConfiguration::ne
             depth_stencil_attachment: None,
             timestamp_writes: None,
             occlusion_query_set: None,
+            multiview_mask: None,
         });
 
         // This viewport is invalid because it has negative size.

tests/tests/wgpu-gpu/main.rs

@@ -36,6 +36,7 @@ mod instance;
 mod life_cycle;
 mod mem_leaks;
 mod mesh_shader;
+mod multiview;
 mod occlusion_query;
 mod oob_indexing;
 mod oom;
@@ -99,6 +100,7 @@ fn all_tests() -> Vec<wgpu_test::GpuTestInitializer> {
     life_cycle::all_tests(&mut tests);
     mem_leaks::all_tests(&mut tests);
     mesh_shader::all_tests(&mut tests);
+    multiview::all_tests(&mut tests);
     occlusion_query::all_tests(&mut tests);
     oob_indexing::all_tests(&mut tests);
     oom::all_tests(&mut tests);

tests/tests/wgpu-gpu/mem_leaks.rs

@@ -126,7 +126,7 @@ async fn draw_test_with_reports(
                     write_mask: wgpu::ColorWrites::ALL,
                 })],
             }),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 
@@ -207,6 +207,7 @@ async fn draw_test_with_reports(
         depth_stencil_attachment: None,
         timestamp_writes: None,
         occlusion_query_set: None,
+        multiview_mask: None,
     });
 
     rpass.set_pipeline(&pipeline);

tests/tests/wgpu-gpu/mesh_shader/mod.rs

@@ -242,6 +242,7 @@ fn mesh_pipeline_build(ctx: &TestingContext, info: MeshPipelineTestInfo) {
                 }),
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
             pass.set_pipeline(&pipeline);
             pass.draw_mesh_tasks(1, 1, 1);
@@ -348,6 +349,7 @@ fn mesh_draw(ctx: &TestingContext, draw_type: DrawType) {
             }),
             timestamp_writes: None,
             occlusion_query_set: None,
+            multiview_mask: None,
         });
         pass.set_pipeline(&pipeline);
         match draw_type {

tests/tests/wgpu-gpu/multiview/mod.rs

@@ -0,0 +1,193 @@
+use std::num::NonZero;
+
+use wgpu::{Features, Limits};
+use wgpu_test::{
+    gpu_test, GpuTestConfiguration, GpuTestInitializer, TestParameters, TestingContext,
+};
+
+pub fn all_tests(vec: &mut Vec<GpuTestInitializer>) {
+    vec.push(DRAW_MULTIVIEW_SINGLE);
+    vec.push(DRAW_MULTIVIEW);
+    vec.push(DRAW_MULTIVIEW_NONCONTIGUOUS);
+}
+
+#[gpu_test]
+static DRAW_MULTIVIEW_SINGLE: GpuTestConfiguration = GpuTestConfiguration::new()
+    .parameters(
+        TestParameters::default()
+            .features(Features::MULTIVIEW)
+            .limits(Limits {
+                max_multiview_view_count: 1,
+                ..Limits::defaults()
+            }),
+    )
+    .run_async(|ctx| run_test(ctx, 0b1));
+
+#[gpu_test]
+static DRAW_MULTIVIEW: GpuTestConfiguration = GpuTestConfiguration::new()
+    .parameters(
+        TestParameters::default()
+            .features(Features::MULTIVIEW)
+            .limits(Limits {
+                max_multiview_view_count: 2,
+                ..Limits::defaults()
+            }),
+    )
+    .run_async(|ctx| run_test(ctx, 0b11));
+
+#[gpu_test]
+static DRAW_MULTIVIEW_NONCONTIGUOUS: GpuTestConfiguration = GpuTestConfiguration::new()
+    .parameters(
+        TestParameters::default()
+            .features(Features::MULTIVIEW | Features::SELECTIVE_MULTIVIEW)
+            .limits(Limits {
+                max_multiview_view_count: 4,
+                ..Limits::defaults()
+            }),
+    )
+    .run_async(|ctx| run_test(ctx, 0b1001));
+
+async fn run_test(ctx: TestingContext, layer_mask: u32) {
+    let num_layers = 32 - layer_mask.leading_zeros();
+
+    let shader_src = include_str!("shader.wgsl");
+
+    let shader = ctx
+        .device
+        .create_shader_module(wgpu::ShaderModuleDescriptor {
+            label: None,
+            source: wgpu::ShaderSource::Wgsl(shader_src.into()),
+        });
+
+    let pipeline_desc = wgpu::RenderPipelineDescriptor {
+        label: None,
+        vertex: wgpu::VertexState {
+            buffers: &[],
+            module: &shader,
+            entry_point: Some("vs_main"),
+            compilation_options: Default::default(),
+        },
+        primitive: wgpu::PrimitiveState::default(),
+        fragment: Some(wgpu::FragmentState {
+            module: &shader,
+            entry_point: Some("fs_main"),
+            compilation_options: Default::default(),
+            targets: &[Some(wgpu::ColorTargetState {
+                format: wgpu::TextureFormat::R8Unorm,
+                blend: None,
+                write_mask: wgpu::ColorWrites::ALL,
+            })],
+        }),
+        multiview_mask: NonZero::new(layer_mask),
+        multisample: Default::default(),
+        layout: None,
+        depth_stencil: None,
+        cache: None,
+    };
+
+    const TEXTURE_SIZE: u32 = 256;
+    let pipeline = ctx.device.create_render_pipeline(&pipeline_desc);
+    let texture = ctx.device.create_texture(&wgpu::TextureDescriptor {
+        label: None,
+        size: wgpu::Extent3d {
+            width: TEXTURE_SIZE,
+            height: TEXTURE_SIZE,
+            depth_or_array_layers: 32 - layer_mask.leading_zeros(),
+        },
+        mip_level_count: 1,
+        sample_count: 1,
+        dimension: wgpu::TextureDimension::D2,
+        format: wgpu::TextureFormat::R8Unorm,
+        usage: wgpu::TextureUsages::RENDER_ATTACHMENT | wgpu::TextureUsages::COPY_SRC,
+        view_formats: &[],
+    });
+    let entire_texture_view = texture.create_view(&wgpu::TextureViewDescriptor {
+        label: None,
+        format: Some(wgpu::TextureFormat::R8Unorm),
+        dimension: Some(wgpu::TextureViewDimension::D2Array),
+        usage: Some(wgpu::TextureUsages::RENDER_ATTACHMENT),
+        aspect: wgpu::TextureAspect::All,
+        base_mip_level: 0,
+        mip_level_count: None,
+        base_array_layer: 0,
+        array_layer_count: Some(num_layers),
+    });
+    let readback_buffer = ctx.device.create_buffer(&wgpu::BufferDescriptor {
+        label: None,
+        size: TEXTURE_SIZE as u64 * TEXTURE_SIZE as u64 * num_layers as u64,
+        usage: wgpu::BufferUsages::COPY_DST | wgpu::BufferUsages::MAP_READ,
+        mapped_at_creation: false,
+    });
+
+    let clear_color = 0.0;
+
+    let mut encoder = ctx
+        .device
+        .create_command_encoder(&wgpu::CommandEncoderDescriptor::default());
+    {
+        let mut rpass = encoder.begin_render_pass(&wgpu::RenderPassDescriptor {
+            label: None,
+            color_attachments: &[Some(wgpu::RenderPassColorAttachment {
+                view: &entire_texture_view,
+                depth_slice: None,
+                resolve_target: None,
+                ops: wgpu::Operations {
+                    load: wgpu::LoadOp::Clear(wgpu::Color::TRANSPARENT),
+                    store: wgpu::StoreOp::Store,
+                },
+            })],
+            depth_stencil_attachment: None,
+            timestamp_writes: None,
+            occlusion_query_set: None,
+            multiview_mask: NonZero::new(layer_mask),
+        });
+        rpass.set_pipeline(&pipeline);
+        rpass.draw(0..6, 0..1);
+    }
+    encoder.copy_texture_to_buffer(
+        wgpu::TexelCopyTextureInfo {
+            texture: &texture,
+            mip_level: 0,
+            origin: wgpu::Origin3d { x: 0, y: 0, z: 0 },
+            aspect: wgpu::TextureAspect::All,
+        },
+        wgpu::TexelCopyBufferInfo {
+            buffer: &readback_buffer,
+            layout: wgpu::TexelCopyBufferLayout {
+                offset: 0,
+                bytes_per_row: Some(TEXTURE_SIZE),
+                rows_per_image: Some(TEXTURE_SIZE),
+            },
+        },
+        wgpu::Extent3d {
+            width: TEXTURE_SIZE,
+            height: TEXTURE_SIZE,
+            depth_or_array_layers: num_layers,
+        },
+    );
+    ctx.queue.submit([encoder.finish()]);
+
+    let slice = readback_buffer.slice(..);
+    slice.map_async(wgpu::MapMode::Read, |_| ());
+
+    ctx.async_poll(wgpu::PollType::wait_indefinitely())
+        .await
+        .unwrap();
+
+    let data = slice.get_mapped_range();
+    let each_texture_size = (TEXTURE_SIZE * TEXTURE_SIZE) as usize;
+    assert_eq!(data.len(), each_texture_size * num_layers as usize);
+    for view_idx in 0..num_layers as usize {
+        let target_value = if (layer_mask & (1 << view_idx)) != 0 {
+            (32 + 64 * view_idx) as u8
+        } else {
+            (clear_color * 255.0) as u8
+        };
+        // Some metal devices automatically initialize stuff to 255, so I decided to use 128 instead of that
+        let failed_value = data[each_texture_size * view_idx..each_texture_size * (view_idx + 1)]
+            .iter()
+            .copied()
+            .find(|b| b.abs_diff(target_value) > 1);
+        assert_eq!(failed_value, None, "Expected {target_value}");
+    }
+}

tests/tests/wgpu-gpu/multiview/shader.wgsl

@@ -0,0 +1,11 @@
+const triangles = array<vec2f, 3>(vec2f(-1.0, -1.0), vec2f(3.0, -1.0), vec2f(-1.0, 3.0));
+
+@vertex
+fn vs_main(@builtin(vertex_index) vertex_index: u32) -> @builtin(position) vec4f {
+    return vec4f(triangles[vertex_index], 0.0, 1.0);
+}
+
+@fragment
+fn fs_main(@builtin(view_index) view_index: u32) -> @location(0) vec4f {
+    return vec4f(f32(view_index) * 0.25 + 0.125);
+}

tests/tests/wgpu-gpu/occlusion_query/mod.rs

@@ -56,7 +56,7 @@ static OCCLUSION_QUERY: GpuTestConfiguration = GpuTestConfiguration::new()
                     bias: wgpu::DepthBiasState::default(),
                 }),
                 multisample: wgpu::MultisampleState::default(),
-                multiview: None,
+                multiview_mask: None,
                 cache: None,
             });
 
@@ -84,6 +84,7 @@ static OCCLUSION_QUERY: GpuTestConfiguration = GpuTestConfiguration::new()
                 }),
                 timestamp_writes: None,
                 occlusion_query_set: Some(&query_set),
+                multiview_mask: None,
             });
             render_pass.set_pipeline(&pipeline);
 

tests/tests/wgpu-gpu/pipeline.rs

@@ -129,7 +129,7 @@ static RENDER_PIPELINE_DEFAULT_LAYOUT_BAD_MODULE: GpuTestConfiguration =
                                 depth_stencil: None,
                                 multisample: Default::default(),
                                 fragment: None,
-                                multiview: None,
+                                multiview_mask: None,
                                 cache: None,
                             });
 
@@ -182,7 +182,7 @@ static RENDER_PIPELINE_DEFAULT_LAYOUT_BAD_BGL_INDEX: GpuTestConfiguration =
                                         write_mask: wgpu::ColorWrites::ALL,
                                     })],
                                 }),
-                                multiview: None,
+                                multiview_mask: None,
                                 cache: None,
                             });
 
@@ -223,7 +223,7 @@ static NO_TARGETLESS_RENDER: GpuTestConfiguration = GpuTestConfiguration::new()
                                 ..Default::default()
                             },
                             fragment: None,
-                            multiview: None,
+                            multiview_mask: None,
                             cache: None,
                         });
                 }

tests/tests/wgpu-gpu/planar_texture/mod.rs

@@ -47,7 +47,7 @@ fn test_planar_texture_creation_sampling(
             },
             depth_stencil: None,
             multisample: wgpu::MultisampleState::default(),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 
@@ -101,6 +101,7 @@ fn test_planar_texture_creation_sampling(
         depth_stencil_attachment: None,
         timestamp_writes: None,
         occlusion_query_set: None,
+        multiview_mask: None,
     });
     rpass.set_pipeline(&pipeline);
     rpass.set_bind_group(0, &bind_group, &[]);
@@ -142,7 +143,7 @@ fn test_planar_texture_rendering(
             },
             depth_stencil: None,
             multisample: wgpu::MultisampleState::default(),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 
@@ -170,7 +171,7 @@ fn test_planar_texture_rendering(
             },
             depth_stencil: None,
             multisample: wgpu::MultisampleState::default(),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 
@@ -190,6 +191,7 @@ fn test_planar_texture_rendering(
             depth_stencil_attachment: None,
             timestamp_writes: None,
             occlusion_query_set: None,
+            multiview_mask: None,
         });
         rpass.set_pipeline(&y_pipeline);
         rpass.draw(0..3, 0..1);
@@ -206,6 +208,7 @@ fn test_planar_texture_rendering(
             depth_stencil_attachment: None,
             timestamp_writes: None,
             occlusion_query_set: None,
+            multiview_mask: None,
         });
         rpass.set_pipeline(&uv_pipeline);
         rpass.draw(0..3, 0..1);

tests/tests/wgpu-gpu/push_constants.rs

@@ -301,7 +301,7 @@ async fn render_pass_test(ctx: &TestingContext, use_render_bundle: bool) {
             },
             depth_stencil: None,
             multisample: MultisampleState::default(),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 

tests/tests/wgpu-gpu/regression/issue_3349.rs

@@ -123,7 +123,7 @@ async fn multi_stage_data_binding_test(ctx: TestingContext) {
             primitive: wgpu::PrimitiveState::default(),
             depth_stencil: None,
             multisample: wgpu::MultisampleState::default(),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 
@@ -166,6 +166,7 @@ async fn multi_stage_data_binding_test(ctx: TestingContext) {
             depth_stencil_attachment: None,
             timestamp_writes: None,
             occlusion_query_set: None,
+            multiview_mask: None,
         });
 
         rpass.set_pipeline(&pipeline);

tests/tests/wgpu-gpu/regression/issue_3457.rs

@@ -84,7 +84,7 @@ static PASS_RESET_VERTEX_BUFFER: GpuTestConfiguration = GpuTestConfiguration::ne
                         write_mask: ColorWrites::all(),
                     })],
                 }),
-                multiview: None,
+                multiview_mask: None,
                 cache: None,
             });
 
@@ -116,7 +116,7 @@ static PASS_RESET_VERTEX_BUFFER: GpuTestConfiguration = GpuTestConfiguration::ne
                         write_mask: ColorWrites::all(),
                     })],
                 }),
-                multiview: None,
+                multiview_mask: None,
                 cache: None,
             });
 
@@ -156,6 +156,7 @@ static PASS_RESET_VERTEX_BUFFER: GpuTestConfiguration = GpuTestConfiguration::ne
             depth_stencil_attachment: None,
             timestamp_writes: None,
             occlusion_query_set: None,
+            multiview_mask: None,
         });
 
         double_rpass.set_pipeline(&double_pipeline);
@@ -192,6 +193,7 @@ static PASS_RESET_VERTEX_BUFFER: GpuTestConfiguration = GpuTestConfiguration::ne
             depth_stencil_attachment: None,
             timestamp_writes: None,
             occlusion_query_set: None,
+            multiview_mask: None,
         });
 
         single_rpass.set_pipeline(&single_pipeline);

tests/tests/wgpu-gpu/regression/issue_4485.rs

@@ -68,7 +68,7 @@ async fn test_impl(ctx: &TestingContext) {
                     write_mask: wgpu::ColorWrites::ALL,
                 })],
             }),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 
@@ -98,6 +98,7 @@ async fn test_impl(ctx: &TestingContext) {
                 depth_stencil_attachment: None,
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
             render_pass.set_pipeline(&pipeline);
             render_pass.draw(0..3, 0..1);

tests/tests/wgpu-gpu/regression/issue_4514.rs

@@ -68,7 +68,7 @@ async fn test_impl(ctx: &TestingContext) {
                     write_mask: wgpu::ColorWrites::ALL,
                 })],
             }),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 
@@ -98,6 +98,7 @@ async fn test_impl(ctx: &TestingContext) {
                 depth_stencil_attachment: None,
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
             render_pass.set_pipeline(&pipeline);
             render_pass.draw(0..3, 0..1);

tests/tests/wgpu-gpu/regression/issue_5553.rs

@@ -53,7 +53,7 @@ static ALLOW_INPUT_NOT_CONSUMED: GpuTestConfiguration = GpuTestConfiguration::ne
                         write_mask: ColorWrites::all(),
                     })],
                 }),
-                multiview: None,
+                multiview_mask: None,
                 cache: None,
             });
     });

tests/tests/wgpu-gpu/render_pass_ownership.rs

@@ -91,6 +91,7 @@ async fn render_pass_resource_ownership(ctx: TestingContext) {
             }),
             timestamp_writes: None,
             occlusion_query_set: Some(&occlusion_query_set),
+            multiview_mask: None,
         });
 
         // Drop render pass attachments right away.
@@ -548,7 +549,7 @@ fn resource_setup(ctx: &TestingContext) -> ResourceSetup {
                 mask: !0,
                 alpha_to_coverage_enabled: false,
             },
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 

tests/tests/wgpu-gpu/render_target.rs

@@ -106,7 +106,7 @@ async fn run_test(
                 write_mask: wgpu::ColorWrites::ALL,
             })],
         }),
-        multiview: None,
+        multiview_mask: None,
         cache: None,
     };
     let pipeline = ctx.device.create_render_pipeline(&pipeline_desc);
@@ -203,6 +203,7 @@ async fn run_test(
                 depth_stencil_attachment: None,
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
             rpass.set_pipeline(&pipeline);
             rpass.set_vertex_buffer(0, vertex_buffer.slice(..));
@@ -318,7 +319,7 @@ async fn run_test_3d(ctx: TestingContext) {
                 write_mask: wgpu::ColorWrites::ALL,
             })],
         }),
-        multiview: None,
+        multiview_mask: None,
         cache: None,
     };
     let pipeline = ctx.device.create_render_pipeline(&pipeline_desc);
@@ -386,6 +387,7 @@ async fn run_test_3d(ctx: TestingContext) {
                 depth_stencil_attachment: None,
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
             rpass.set_pipeline(&pipeline);
             rpass.set_vertex_buffer(0, vertex_buffer.slice(..));

tests/tests/wgpu-gpu/scissor_tests/mod.rs

@@ -69,7 +69,7 @@ async fn scissor_test_impl(
                     write_mask: wgpu::ColorWrites::ALL,
                 })],
             }),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 
@@ -98,6 +98,7 @@ async fn scissor_test_impl(
                 depth_stencil_attachment: None,
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
             render_pass.set_pipeline(&pipeline);
             render_pass.set_scissor_rect(

tests/tests/wgpu-gpu/shader_barycentric/mod.rs

@@ -95,7 +95,7 @@ async fn barycentric(ctx: TestingContext) {
                     write_mask: wgpu::ColorWrites::ALL,
                 })],
             }),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 
@@ -138,6 +138,7 @@ async fn barycentric(ctx: TestingContext) {
             depth_stencil_attachment: None,
             timestamp_writes: None,
             occlusion_query_set: None,
+            multiview_mask: None,
         });
 
         rpass.set_pipeline(&pipeline);

tests/tests/wgpu-gpu/shader_primitive_index/mod.rs

@@ -150,7 +150,7 @@ async fn pulling_common(
                     write_mask: wgpu::ColorWrites::ALL,
                 })],
             }),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
 
@@ -193,6 +193,7 @@ async fn pulling_common(
             depth_stencil_attachment: None,
             timestamp_writes: None,
             occlusion_query_set: None,
+            multiview_mask: None,
         });
 
         rpass.set_pipeline(&pipeline);

tests/tests/wgpu-gpu/shader_view_format/mod.rs

@@ -113,7 +113,7 @@ async fn reinterpret(
             },
             depth_stencil: None,
             multisample: wgpu::MultisampleState::default(),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         });
     let bind_group = ctx.device.create_bind_group(&wgpu::BindGroupDescriptor {
@@ -151,6 +151,7 @@ async fn reinterpret(
         depth_stencil_attachment: None,
         timestamp_writes: None,
         occlusion_query_set: None,
+        multiview_mask: None,
     });
     rpass.set_pipeline(&pipeline);
     rpass.set_bind_group(0, &bind_group, &[]);

tests/tests/wgpu-gpu/transient.rs

@@ -64,7 +64,7 @@ static RESOLVE_WITH_TRANSIENT: GpuTestConfiguration = GpuTestConfiguration::new(
                     write_mask: wgpu::ColorWrites::ALL,
                 })],
             }),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         };
         let pipeline = ctx.device.create_render_pipeline(&pipeline_desc);
@@ -119,6 +119,7 @@ static RESOLVE_WITH_TRANSIENT: GpuTestConfiguration = GpuTestConfiguration::new(
                 depth_stencil_attachment: None,
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
 
             rpass.set_pipeline(&pipeline);

tests/tests/wgpu-gpu/vertex_formats/mod.rs

@@ -314,7 +314,7 @@ async fn vertex_formats_common(ctx: TestingContext, tests: &[Test<'_>]) {
                     write_mask: wgpu::ColorWrites::ALL,
                 })],
             }),
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         };
 
@@ -360,6 +360,7 @@ async fn vertex_formats_common(ctx: TestingContext, tests: &[Test<'_>]) {
             depth_stencil_attachment: None,
             timestamp_writes: None,
             occlusion_query_set: None,
+            multiview_mask: None,
         });
 
         rpass.set_vertex_buffer(0, buffer_input.slice(..));

tests/tests/wgpu-gpu/vertex_indices/mod.rs

@@ -259,7 +259,7 @@ async fn vertex_index_common(ctx: TestingContext) {
                 write_mask: wgpu::ColorWrites::ALL,
             })],
         }),
-        multiview: None,
+        multiview_mask: None,
         cache: None,
     };
     let builtin_pipeline = ctx.device.create_render_pipeline(&pipeline_desc);
@@ -366,6 +366,7 @@ async fn vertex_index_common(ctx: TestingContext) {
             depth_stencil_attachment: None,
             timestamp_writes: None,
             occlusion_query_set: None,
+            multiview_mask: None,
         });
 
         {

tests/tests/wgpu-gpu/vertex_state.rs

@@ -99,7 +99,7 @@ async fn set_array_stride_to_0(ctx: TestingContext) {
                 write_mask: wgpu::ColorWrites::ALL,
             })],
         }),
-        multiview: None,
+        multiview_mask: None,
         cache: None,
     };
     let mut first_pipeline_desc = pipeline_desc.clone();
@@ -148,6 +148,7 @@ async fn set_array_stride_to_0(ctx: TestingContext) {
             depth_stencil_attachment: None,
             timestamp_writes: None,
             occlusion_query_set: None,
+            multiview_mask: None,
         });
 
         // The D3D12 backend used to not set the stride of vertex buffers if it was 0.

tests/tests/wgpu-gpu/zero_init_texture_after_discard.rs

@@ -173,6 +173,7 @@ impl<'ctx> TestCase<'ctx> {
                 }),
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
             ctx.queue.submit([encoder.finish()]);
         } else {
@@ -259,6 +260,7 @@ impl<'ctx> TestCase<'ctx> {
                 ),
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
     }
 
@@ -284,6 +286,7 @@ impl<'ctx> TestCase<'ctx> {
                 ),
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
     }
 
@@ -309,6 +312,7 @@ impl<'ctx> TestCase<'ctx> {
                 ),
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
     }
 

tests/tests/wgpu-validation/api/external_texture.rs

@@ -652,7 +652,7 @@ var tex: texture_external;
                 write_mask: ColorWrites::ALL,
             })],
         }),
-        multiview: None,
+        multiview_mask: None,
         cache: None,
     });
 
@@ -685,6 +685,7 @@ var tex: texture_external;
         depth_stencil_attachment: None,
         timestamp_writes: None,
         occlusion_query_set: None,
+        multiview_mask: None,
     });
 
     pass.set_pipeline(&pipeline);

tests/tests/wgpu-validation/api/render_pipeline.rs

@@ -58,7 +58,7 @@ fn frag() -> @location({}) vec4f {{
                 primitive: Default::default(),
                 depth_stencil: None,
                 multisample: Default::default(),
-                multiview: None,
+                multiview_mask: None,
                 cache: None,
             })
         },

tests/tests/wgpu-validation/api/texture.rs

@@ -674,6 +674,7 @@ fn transient_invalid_storeop() {
                 depth_stencil_attachment: None,
                 timestamp_writes: None,
                 occlusion_query_set: None,
+                multiview_mask: None,
             });
 
             drop(invalid_render_pass);

wgpu-core/src/command/bundle.rs

@@ -218,7 +218,7 @@ impl RenderBundleEncoder {
                     }
                     sc
                 },
-                multiview: desc.multiview,
+                multiview_mask: desc.multiview,
             },
 
             is_depth_read_only,
@@ -239,7 +239,7 @@ impl RenderBundleEncoder {
                     depth_stencil: None,
                 },
                 sample_count: 0,
-                multiview: None,
+                multiview_mask: None,
             },
             is_depth_read_only: false,
             is_stencil_read_only: false,

wgpu-core/src/command/clear.rs

@@ -532,7 +532,7 @@ fn clear_texture_via_render_passes(
                         sample_count: dst_texture.desc.sample_count,
                         color_attachments,
                         depth_stencil_attachment,
-                        multiview: None,
+                        multiview_mask: None,
                         timestamp_writes: None,
                         occlusion_query_set: None,
                     })

wgpu-core/src/command/draw.rs

@@ -71,6 +71,13 @@ pub enum DrawError {
         limit: u32,
         max_total: u32,
     },
+    #[error(
+        "Mesh shader calls in multiview render passes require enabling the `EXPERIMENTAL_MESH_SHADER_MULTIVIEW` feature, and the highest bit ({highest_view_index}) in the multiview mask must be <= `Limits::max_multiview_view_count` ({max_multiviews})"
+    )]
+    MeshPipelineMultiviewLimitsViolated {
+        highest_view_index: u32,
+        max_multiviews: u32,
+    },
 }
 
 impl WebGpuError for DrawError {

wgpu-core/src/command/encoder_command.rs

@@ -1,4 +1,4 @@
-use core::convert::Infallible;
+use core::{convert::Infallible, num::NonZero};
 
 use alloc::{string::String, sync::Arc, vec::Vec};
 #[cfg(feature = "serde")]
@@ -171,6 +171,7 @@ pub enum Command<R: ReferenceType> {
             Option<crate::command::ResolvedRenderPassDepthStencilAttachment<R::TextureView>>,
         timestamp_writes: Option<crate::command::PassTimestampWrites<R::QuerySet>>,
         occlusion_query_set: Option<R::QuerySet>,
+        multiview_mask: Option<NonZero<u32>>,
     },
     BuildAccelerationStructures {
         blas: Vec<crate::ray_tracing::OwnedBlasBuildEntry<R>>,

wgpu-core/src/command/mod.rs

@@ -1019,6 +1019,7 @@ impl CommandEncoder {
                             depth_stencil_attachment,
                             timestamp_writes,
                             occlusion_query_set,
+                            multiview_mask,
                         } => {
                             api_log!(
                                 "Begin encoding render pass with '{}' label",
@@ -1031,6 +1032,7 @@ impl CommandEncoder {
                                 depth_stencil_attachment,
                                 timestamp_writes,
                                 occlusion_query_set,
+                                multiview_mask,
                             );
                             match res.as_ref() {
                                 Err(err) => api_log!("Finished encoding render pass ({err:?})"),

wgpu-core/src/command/render.rs

@@ -250,6 +250,8 @@ pub struct RenderPassDescriptor<'a> {
     pub timestamp_writes: Option<&'a PassTimestampWrites>,
     /// Defines where the occlusion query results will be stored for this pass.
     pub occlusion_query_set: Option<id::QuerySetId>,
+    /// The multiview array layers that will be used
+    pub multiview_mask: Option<NonZeroU32>,
 }
 
 /// Describes the attachments of a render pass.
@@ -265,6 +267,8 @@ struct ArcRenderPassDescriptor<'a> {
     pub timestamp_writes: Option<ArcPassTimestampWrites>,
     /// Defines where the occlusion query results will be stored for this pass.
     pub occlusion_query_set: Option<Arc<QuerySet>>,
+    /// The multiview array layers that will be used
+    pub multiview_mask: Option<NonZeroU32>,
 }
 
 pub type RenderBasePass = BasePass<ArcRenderCommand, RenderPassError>;
@@ -292,6 +296,7 @@ pub struct RenderPass {
     depth_stencil_attachment: Option<ResolvedRenderPassDepthStencilAttachment<Arc<TextureView>>>,
     timestamp_writes: Option<ArcPassTimestampWrites>,
     occlusion_query_set: Option<Arc<QuerySet>>,
+    multiview_mask: Option<NonZeroU32>,
 
     // Resource binding dedupe state.
     current_bind_groups: BindGroupStateChange,
@@ -307,6 +312,7 @@ impl RenderPass {
             color_attachments,
             depth_stencil_attachment,
             occlusion_query_set,
+            multiview_mask,
         } = desc;
 
         Self {
@@ -316,6 +322,7 @@ impl RenderPass {
             depth_stencil_attachment,
             timestamp_writes,
             occlusion_query_set,
+            multiview_mask,
 
             current_bind_groups: BindGroupStateChange::new(),
             current_pipeline: StateChange::new(),
@@ -330,6 +337,7 @@ impl RenderPass {
             depth_stencil_attachment: None,
             timestamp_writes: None,
             occlusion_query_set: None,
+            multiview_mask: None,
             current_bind_groups: BindGroupStateChange::new(),
             current_pipeline: StateChange::new(),
         }
@@ -353,6 +361,7 @@ impl fmt::Debug for RenderPass {
                 "push constant u32 count",
                 &self.base.push_constant_data.len(),
             )
+            .field("multiview mask", &self.multiview_mask)
             .finish()
     }
 }
@@ -806,6 +815,8 @@ pub enum RenderPassErrorInner {
         "Multiview pass texture views with more than one array layer must have D2Array dimension"
     )]
     MultiViewDimensionMismatch,
+    #[error("Multiview view count limit violated")]
+    TooManyMultiviewViews,
     #[error("missing occlusion query set")]
     MissingOcclusionQuerySet,
     #[error(transparent)]
@@ -907,6 +918,7 @@ impl WebGpuError for RenderPassError {
             | RenderPassErrorInner::PushConstantOutOfMemory
             | RenderPassErrorInner::MultiViewMismatch
             | RenderPassErrorInner::MultiViewDimensionMismatch
+            | RenderPassErrorInner::TooManyMultiviewViews
             | RenderPassErrorInner::MissingOcclusionQuerySet
             | RenderPassErrorInner::PassEnded => return ErrorType::Validation,
         };
@@ -942,7 +954,7 @@ struct RenderPassInfo {
     extent: wgt::Extent3d,
 
     divergent_discarded_depth_stencil_aspect: Option<(wgt::TextureAspect, Arc<TextureView>)>,
-    multiview: Option<NonZeroU32>,
+    multiview_mask: Option<NonZeroU32>,
 }
 
 impl RenderPassInfo {
@@ -996,6 +1008,7 @@ impl RenderPassInfo {
         pending_query_resets: &mut QueryResetMap,
         pending_discard_init_fixups: &mut SurfacesInDiscardState,
         snatch_guard: &SnatchGuard<'_>,
+        multiview_mask: Option<NonZeroU32>,
     ) -> Result<Self, RenderPassErrorInner> {
         profiling::scope!("RenderPassInfo::start");
 
@@ -1040,8 +1053,11 @@ impl RenderPassInfo {
                 }
             } else {
                 // Multiview is only supported if the feature is enabled
-                if this_multiview.is_some() {
+                if let Some(this_multiview) = this_multiview {
                     device.require_features(wgt::Features::MULTIVIEW)?;
+                    if this_multiview.get() > device.limits.max_multiview_view_count {
+                        return Err(RenderPassErrorInner::TooManyMultiviewViews);
+                    }
                 }
 
                 detected_multiview = Some(this_multiview);
@@ -1389,7 +1405,20 @@ impl RenderPassInfo {
         }
 
         let extent = extent.ok_or(RenderPassErrorInner::MissingAttachments)?;
-        let multiview = detected_multiview.expect("Multiview was not detected, no attachments");
+
+        let detected_multiview =
+            detected_multiview.expect("Multiview was not detected, no attachments");
+        if let Some(mask) = multiview_mask {
+            // 0x01 will have msb 0
+            let mask_msb = 31 - mask.leading_zeros();
+            let detected_mv = detected_multiview.map(NonZeroU32::get).unwrap_or(1);
+            if mask_msb >= detected_mv {
+                return Err(RenderPassErrorInner::MultiViewMismatch);
+            }
+            if mask.get() != (1 << detected_mv) - 1 {
+                device.require_features(wgt::Features::SELECTIVE_MULTIVIEW)?;
+            }
+        }
 
         let attachment_formats = AttachmentData {
             colors: color_attachments
@@ -1414,7 +1443,7 @@ impl RenderPassInfo {
         let context = RenderPassContext {
             attachments: attachment_formats,
             sample_count,
-            multiview,
+            multiview_mask,
         };
 
         let timestamp_writes_hal = if let Some(tw) = timestamp_writes.as_ref() {
@@ -1450,7 +1479,7 @@ impl RenderPassInfo {
             sample_count,
             color_attachments: &color_attachments_hal,
             depth_stencil_attachment: depth_stencil,
-            multiview,
+            multiview_mask,
             timestamp_writes: timestamp_writes_hal,
             occlusion_query_set: occlusion_query_set_hal,
         };
@@ -1485,7 +1514,7 @@ impl RenderPassInfo {
             is_stencil_read_only,
             extent,
             divergent_discarded_depth_stencil_aspect,
-            multiview,
+            multiview_mask,
         })
     }
 
@@ -1552,7 +1581,7 @@ impl RenderPassInfo {
                     stencil_ops,
                     clear_value: (0.0, 0),
                 }),
-                multiview: self.multiview,
+                multiview_mask: self.multiview_mask,
                 timestamp_writes: None,
                 occlusion_query_set: None,
             };
@@ -1713,6 +1742,8 @@ impl Global {
                     None
                 };
 
+            arc_desc.multiview_mask = desc.multiview_mask;
+
             Ok(())
         }
 
@@ -1731,6 +1762,7 @@ impl Global {
                     color_attachments: ArrayVec::new(),
                     depth_stencil_attachment: None,
                     occlusion_query_set: None,
+                    multiview_mask: None,
                 };
                 match fill_arc_desc(hub, desc, &mut arc_desc, &cmd_enc.device) {
                     Ok(()) => (RenderPass::new(cmd_enc, arc_desc), None),
@@ -1816,6 +1848,7 @@ impl Global {
                 depth_stencil_attachment: pass.depth_stencil_attachment.take(),
                 timestamp_writes: pass.timestamp_writes.take(),
                 occlusion_query_set: pass.occlusion_query_set.take(),
+                multiview_mask: pass.multiview_mask,
             })
         })
     }
@@ -1830,6 +1863,7 @@ pub(super) fn encode_render_pass(
     >,
     mut timestamp_writes: Option<ArcPassTimestampWrites>,
     occlusion_query_set: Option<Arc<QuerySet>>,
+    multiview_mask: Option<NonZeroU32>,
 ) -> Result<(), RenderPassError> {
     let pass_scope = PassErrorScope::Pass;
 
@@ -1868,6 +1902,7 @@ pub(super) fn encode_render_pass(
             &mut pending_query_resets,
             &mut pending_discard_init_fixups,
             parent_state.snatch_guard,
+            multiview_mask,
         )
         .map_pass_err(pass_scope)?;
 
@@ -2561,6 +2596,26 @@ fn set_scissor(state: &mut State, rect: Rect<u32>) -> Result<(), RenderPassError
     Ok(())
 }
 
+fn validate_mesh_draw_multiview(state: &State) -> Result<(), RenderPassErrorInner> {
+    if let Some(mv) = state.info.multiview_mask {
+        let highest_bit = 31 - mv.leading_zeros();
+
+        let features = state.pass.base.device.features;
+
+        if !features.contains(wgt::Features::EXPERIMENTAL_MESH_SHADER_MULTIVIEW)
+            || highest_bit > state.pass.base.device.limits.max_mesh_multiview_view_count
+        {
+            return Err(RenderPassErrorInner::Draw(
+                DrawError::MeshPipelineMultiviewLimitsViolated {
+                    highest_view_index: highest_bit,
+                    max_multiviews: state.pass.base.device.limits.max_mesh_multiview_view_count,
+                },
+            ));
+        }
+    }
+    Ok(())
+}
+
 fn draw(
     state: &mut State,
     vertex_count: u32,
@@ -2645,7 +2700,9 @@ fn draw_mesh_tasks(
     api_log!("RenderPass::draw_mesh_tasks {group_count_x} {group_count_y} {group_count_z}");
 
     state.is_ready(DrawCommandFamily::DrawMeshTasks)?;
+
     state.flush_bindings()?;
+    validate_mesh_draw_multiview(state)?;
 
     let groups_size_limit = state
         .pass
@@ -2696,6 +2753,10 @@ fn multi_draw_indirect(
     state.is_ready(family)?;
     state.flush_bindings()?;
 
+    if family == DrawCommandFamily::DrawMeshTasks {
+        validate_mesh_draw_multiview(state)?;
+    }
+
     state
         .pass
         .base
@@ -2878,6 +2939,10 @@ fn multi_draw_indirect_count(
     state.is_ready(family)?;
     state.flush_bindings()?;
 
+    if family == DrawCommandFamily::DrawMeshTasks {
+        validate_mesh_draw_multiview(state)?;
+    }
+
     let stride = get_stride_of_indirect_args(family);
 
     state

wgpu-core/src/device/global.rs

@@ -1478,7 +1478,7 @@ impl Global {
                 depth_stencil: desc.depth_stencil.clone(),
                 multisample: desc.multisample,
                 fragment,
-                multiview: desc.multiview,
+                multiview_mask: desc.multiview_mask,
                 cache,
             };
 

wgpu-core/src/device/mod.rs

@@ -61,7 +61,7 @@ impl<T: PartialEq> Eq for AttachmentData<T> {}
 pub(crate) struct RenderPassContext {
     pub attachments: AttachmentData<TextureFormat>,
     pub sample_count: u32,
-    pub multiview: Option<NonZeroU32>,
+    pub multiview_mask: Option<NonZeroU32>,
 }
 #[derive(Clone, Debug, Error)]
 #[non_exhaustive]
@@ -144,10 +144,10 @@ impl RenderPassContext {
                 res: res.error_ident(),
             });
         }
-        if self.multiview != other.multiview {
+        if self.multiview_mask != other.multiview_mask {
             return Err(RenderPassCompatibilityError::IncompatibleMultiview {
-                expected: self.multiview,
-                actual: other.multiview,
+                expected: self.multiview_mask,
+                actual: other.multiview_mask,
                 res: res.error_ident(),
             });
         }

wgpu-core/src/device/resource.rs

@@ -4442,8 +4442,11 @@ impl Device {
         };
 
         // Multiview is only supported if the feature is enabled
-        if desc.multiview.is_some() {
+        if let Some(mv_mask) = desc.multiview_mask {
             self.require_features(wgt::Features::MULTIVIEW)?;
+            if !(mv_mask.get() + 1).is_power_of_two() {
+                self.require_features(wgt::Features::SELECTIVE_MULTIVIEW)?;
+            }
         }
 
         if !self
@@ -4493,7 +4496,7 @@ impl Device {
                 multisample: desc.multisample,
                 fragment_stage,
                 color_targets,
-                multiview: desc.multiview,
+                multiview_mask: desc.multiview_mask,
                 cache: cache.as_ref().map(|it| it.raw()),
             };
             unsafe { self.raw().create_render_pipeline(&pipeline_desc) }.map_err(
@@ -4527,7 +4530,7 @@ impl Device {
                 depth_stencil: depth_stencil_state.as_ref().map(|state| state.format),
             },
             sample_count: samples,
-            multiview: desc.multiview,
+            multiview_mask: desc.multiview_mask,
         };
 
         let mut flags = pipeline::PipelineFlags::empty();

wgpu-core/src/device/trace/record.rs

@@ -39,7 +39,7 @@ pub(crate) fn new_render_bundle_encoder_descriptor(
             }
         }),
         sample_count: context.sample_count,
-        multiview: context.multiview,
+        multiview: context.multiview_mask,
     }
 }
 
@@ -195,12 +195,14 @@ impl IntoTrace for ArcCommand {
                 depth_stencil_attachment,
                 timestamp_writes,
                 occlusion_query_set,
+                multiview_mask,
             } => Command::RunRenderPass {
                 pass: pass.into_trace(),
                 color_attachments: color_attachments.into_trace(),
                 depth_stencil_attachment: depth_stencil_attachment.map(|d| d.into_trace()),
                 timestamp_writes: timestamp_writes.map(|tw| tw.into_trace()),
                 occlusion_query_set: occlusion_query_set.map(|q| q.to_trace()),
+                multiview_mask,
             },
             ArcCommand::BuildAccelerationStructures { blas, tlas } => {
                 Command::BuildAccelerationStructures {
@@ -660,7 +662,7 @@ impl<'a> IntoTrace for crate::pipeline::ResolvedGeneralRenderPipelineDescriptor<
             depth_stencil: self.depth_stencil,
             multisample: self.multisample,
             fragment: self.fragment.map(|f| f.into_trace()),
-            multiview: self.multiview,
+            multiview_mask: self.multiview_mask,
             cache: self.cache.map(|c| c.into_trace()),
         }
     }

wgpu-core/src/pipeline.rs

@@ -467,7 +467,7 @@ pub struct RenderPipelineDescriptor<
     pub fragment: Option<FragmentState<'a, SM>>,
     /// If the pipeline will be used with a multiview render pass, this indicates how many array
     /// layers the attachments will have.
-    pub multiview: Option<NonZeroU32>,
+    pub multiview_mask: Option<NonZeroU32>,
     /// The pipeline cache to use when creating this pipeline.
     pub cache: Option<PLC>,
 }
@@ -539,7 +539,7 @@ pub struct GeneralRenderPipelineDescriptor<
     pub fragment: Option<FragmentState<'a, SM>>,
     /// If the pipeline will be used with a multiview render pass, this indicates how many array
     /// layers the attachments will have.
-    pub multiview: Option<NonZeroU32>,
+    pub multiview_mask: Option<NonZeroU32>,
     /// The pipeline cache to use when creating this pipeline.
     pub cache: Option<PLC>,
 }
@@ -555,7 +555,7 @@ impl<'a, PLL, SM, PLC> From<RenderPipelineDescriptor<'a, PLL, SM, PLC>>
             depth_stencil: value.depth_stencil,
             multisample: value.multisample,
             fragment: value.fragment,
-            multiview: value.multiview,
+            multiview_mask: value.multiview_mask,
             cache: value.cache,
         }
     }
@@ -572,7 +572,7 @@ impl<'a, PLL, SM, PLC> From<MeshPipelineDescriptor<'a, PLL, SM, PLC>>
             depth_stencil: value.depth_stencil,
             multisample: value.multisample,
             fragment: value.fragment,
-            multiview: value.multiview,
+            multiview_mask: value.multiview,
             cache: value.cache,
         }
     }

wgpu-hal/Cargo.toml

@@ -84,6 +84,7 @@ metal = [
     "dep:objc",
     "dep:parking_lot",
     "dep:profiling",
+    "dep:smallvec",
 ]
 vulkan = [
     "naga/spv-out",

wgpu-hal/examples/halmark/main.rs

@@ -280,7 +280,7 @@ impl<A: hal::Api> Example<A> {
                 blend: Some(wgpu_types::BlendState::ALPHA_BLENDING),
                 write_mask: wgpu_types::ColorWrites::default(),
             })],
-            multiview: None,
+            multiview_mask: None,
             cache: None,
         };
         let pipeline = unsafe { device.create_render_pipeline(&pipeline_desc).unwrap() };
@@ -727,7 +727,7 @@ impl<A: hal::Api> Example<A> {
                 },
             })],
             depth_stencil_attachment: None,
-            multiview: None,
+            multiview_mask: None,
             timestamp_writes: None,
             occlusion_query_set: None,
         };

wgpu-hal/examples/raw-gles.rs

@@ -329,7 +329,7 @@ fn fill_screen(exposed: &hal::ExposedAdapter<hal::api::Gles>, width: u32, height
             clear_value: wgpu_types::Color::BLUE,
         })],
         depth_stencil_attachment: None,
-        multiview: None,
+        multiview_mask: None,
         timestamp_writes: None,
         occlusion_query_set: None,
     };