add a debug label to storage buffers (#5341)

# Objective

- Expose the wgpu debug label on storage buffer types.

## Solution

🐄

- Add an optional cow static string and pass that to the label field of create_buffer_with_data
- This pattern is already used by Bevy for debug tags on bind group and layout descriptors.

---

Example Usage:

A buffer is given a label using the label function. Alternatively a buffer may be labeled when it is created if the default() convention is not used.
![ray_buf](https://user-images.githubusercontent.com/106117615/179366494-f037bd8c-4d65-4b37-8135-01ac0c5c8ee0.png)

Here is the buffer appearing with the correct name in RenderDoc. Previously the buffer would have an anonymous name such as "Buffer223":
![buffer_named](https://user-images.githubusercontent.com/106117615/179366552-faeb6c27-5373-4e4e-a0e2-c04446f95a4b.png)



Co-authored-by: rebelroad-reinhart <reinhart@rebelroad.gg>

crates/bevy_render/src/render_resource/buffer_vec.rs

@@ -33,6 +33,8 @@ pub struct BufferVec<T: Pod> {
     capacity: usize,
     item_size: usize,
     buffer_usage: BufferUsages,
+    label: Option<String>,
+    label_changed: bool,
 }
 
 impl<T: Pod> BufferVec<T> {
@@ -43,6 +45,8 @@ impl<T: Pod> BufferVec<T> {
             capacity: 0,
             item_size: std::mem::size_of::<T>(),
             buffer_usage,
+            label: None,
+            label_changed: false,
         }
     }
 
@@ -72,6 +76,20 @@ impl<T: Pod> BufferVec<T> {
         index
     }
 
+    pub fn set_label(&mut self, label: Option<&str>) {
+        let label = label.map(str::to_string);
+
+        if label != self.label {
+            self.label_changed = true;
+        }
+
+        self.label = label;
+    }
+
+    pub fn get_label(&self) -> Option<&str> {
+        self.label.as_deref()
+    }
+
     /// Creates a [`Buffer`](crate::render_resource::Buffer) on the [`RenderDevice`](crate::renderer::RenderDevice) with size
     /// at least `std::mem::size_of::<T>() * capacity`, unless a such a buffer already exists.
     ///
@@ -84,15 +102,16 @@ impl<T: Pod> BufferVec<T> {
     /// the `BufferVec` was created, the buffer on the [`RenderDevice`](crate::renderer::RenderDevice)
     /// is marked as [`BufferUsages::COPY_DST`](crate::render_resource::BufferUsages).
     pub fn reserve(&mut self, capacity: usize, device: &RenderDevice) {
-        if capacity > self.capacity {
+        if capacity > self.capacity || self.label_changed {
             self.capacity = capacity;
             let size = self.item_size * capacity;
             self.buffer = Some(device.create_buffer(&wgpu::BufferDescriptor {
-                label: None,
+                label: self.label.as_deref(),
                 size: size as wgpu::BufferAddress,
                 usage: BufferUsages::COPY_DST | self.buffer_usage,
                 mapped_at_creation: false,
             }));
+            self.label_changed = false;
         }
     }
 

crates/bevy_render/src/render_resource/storage_buffer.rs

@@ -32,6 +32,8 @@ pub struct StorageBuffer<T: ShaderType> {
     scratch: StorageBufferWrapper<Vec<u8>>,
     buffer: Option<Buffer>,
     capacity: usize,
+    label: Option<String>,
+    label_changed: bool,
 }
 
 impl<T: ShaderType> From<T> for StorageBuffer<T> {
@@ -41,6 +43,8 @@ impl<T: ShaderType> From<T> for StorageBuffer<T> {
             scratch: StorageBufferWrapper::new(Vec::new()),
             buffer: None,
             capacity: 0,
+            label: None,
+            label_changed: false,
         }
     }
 }
@@ -52,6 +56,8 @@ impl<T: ShaderType + Default> Default for StorageBuffer<T> {
             scratch: StorageBufferWrapper::new(Vec::new()),
             buffer: None,
             capacity: 0,
+            label: None,
+            label_changed: false,
         }
     }
 }
@@ -81,6 +87,20 @@ impl<T: ShaderType + WriteInto> StorageBuffer<T> {
         &mut self.value
     }
 
+    pub fn set_label(&mut self, label: Option<&str>) {
+        let label = label.map(str::to_string);
+
+        if label != self.label {
+            self.label_changed = true;
+        }
+
+        self.label = label;
+    }
+
+    pub fn get_label(&self) -> Option<&str> {
+        self.label.as_deref()
+    }
+
     /// Queues writing of data from system RAM to VRAM using the [`RenderDevice`](crate::renderer::RenderDevice)
     /// and the provided [`RenderQueue`](crate::renderer::RenderQueue).
     ///
@@ -91,13 +111,14 @@ impl<T: ShaderType + WriteInto> StorageBuffer<T> {
 
         let size = self.scratch.as_ref().len();
 
-        if self.capacity < size {
+        if self.capacity < size || self.label_changed {
             self.buffer = Some(device.create_buffer_with_data(&BufferInitDescriptor {
-                label: None,
+                label: self.label.as_deref(),
                 usage: BufferUsages::COPY_DST | BufferUsages::STORAGE,
                 contents: self.scratch.as_ref(),
             }));
             self.capacity = size;
+            self.label_changed = false;
         } else if let Some(buffer) = &self.buffer {
             queue.write_buffer(buffer, 0, self.scratch.as_ref());
         }
@@ -130,6 +151,8 @@ pub struct DynamicStorageBuffer<T: ShaderType> {
     scratch: DynamicStorageBufferWrapper<Vec<u8>>,
     buffer: Option<Buffer>,
     capacity: usize,
+    label: Option<String>,
+    label_changed: bool,
 }
 
 impl<T: ShaderType> Default for DynamicStorageBuffer<T> {
@@ -139,6 +162,8 @@ impl<T: ShaderType> Default for DynamicStorageBuffer<T> {
             scratch: DynamicStorageBufferWrapper::new(Vec::new()),
             buffer: None,
             capacity: 0,
+            label: None,
+            label_changed: false,
         }
     }
 }
@@ -175,17 +200,32 @@ impl<T: ShaderType + WriteInto> DynamicStorageBuffer<T> {
         offset
     }
 
+    pub fn set_label(&mut self, label: Option<&str>) {
+        let label = label.map(str::to_string);
+
+        if label != self.label {
+            self.label_changed = true;
+        }
+
+        self.label = label;
+    }
+
+    pub fn get_label(&self) -> Option<&str> {
+        self.label.as_deref()
+    }
+
     #[inline]
     pub fn write_buffer(&mut self, device: &RenderDevice, queue: &RenderQueue) {
         let size = self.scratch.as_ref().len();
 
-        if self.capacity < size {
+        if self.capacity < size || self.label_changed {
             self.buffer = Some(device.create_buffer_with_data(&BufferInitDescriptor {
-                label: None,
+                label: self.label.as_deref(),
                 usage: BufferUsages::COPY_DST | BufferUsages::STORAGE,
                 contents: self.scratch.as_ref(),
             }));
             self.capacity = size;
+            self.label_changed = false;
         } else if let Some(buffer) = &self.buffer {
             queue.write_buffer(buffer, 0, self.scratch.as_ref());
         }

crates/bevy_render/src/render_resource/uniform_buffer.rs

@@ -31,6 +31,8 @@ pub struct UniformBuffer<T: ShaderType> {
     value: T,
     scratch: UniformBufferWrapper<Vec<u8>>,
     buffer: Option<Buffer>,
+    label: Option<String>,
+    label_changed: bool,
 }
 
 impl<T: ShaderType> From<T> for UniformBuffer<T> {
@@ -39,6 +41,8 @@ impl<T: ShaderType> From<T> for UniformBuffer<T> {
             value,
             scratch: UniformBufferWrapper::new(Vec::new()),
             buffer: None,
+            label: None,
+            label_changed: false,
         }
     }
 }
@@ -49,6 +53,8 @@ impl<T: ShaderType + Default> Default for UniformBuffer<T> {
             value: T::default(),
             scratch: UniformBufferWrapper::new(Vec::new()),
             buffer: None,
+            label: None,
+            label_changed: false,
         }
     }
 }
@@ -79,6 +85,20 @@ impl<T: ShaderType + WriteInto> UniformBuffer<T> {
         &mut self.value
     }
 
+    pub fn set_label(&mut self, label: Option<&str>) {
+        let label = label.map(str::to_string);
+
+        if label != self.label {
+            self.label_changed = true;
+        }
+
+        self.label = label;
+    }
+
+    pub fn get_label(&self) -> Option<&str> {
+        self.label.as_deref()
+    }
+
     /// Queues writing of data from system RAM to VRAM using the [`RenderDevice`](crate::renderer::RenderDevice)
     /// and the provided [`RenderQueue`](crate::renderer::RenderQueue), if a GPU-side backing buffer already exists.
     ///
@@ -87,15 +107,15 @@ impl<T: ShaderType + WriteInto> UniformBuffer<T> {
     pub fn write_buffer(&mut self, device: &RenderDevice, queue: &RenderQueue) {
         self.scratch.write(&self.value).unwrap();
 
-        match &self.buffer {
+        if self.label_changed || self.buffer.is_none() {
-            Some(buffer) => queue.write_buffer(buffer, 0, self.scratch.as_ref()),
+            self.buffer = Some(device.create_buffer_with_data(&BufferInitDescriptor {
-            None => {
+                label: self.label.as_deref(),
-                self.buffer = Some(device.create_buffer_with_data(&BufferInitDescriptor {
+                usage: BufferUsages::COPY_DST | BufferUsages::UNIFORM,
-                    label: None,
+                contents: self.scratch.as_ref(),
-                    usage: BufferUsages::COPY_DST | BufferUsages::UNIFORM,
+            }));
-                    contents: self.scratch.as_ref(),
+            self.label_changed = false;
-                }));
+        } else if let Some(buffer) = &self.buffer {
-            }
+            queue.write_buffer(buffer, 0, self.scratch.as_ref());
         }
     }
 }
@@ -124,6 +144,8 @@ pub struct DynamicUniformBuffer<T: ShaderType> {
     scratch: DynamicUniformBufferWrapper<Vec<u8>>,
     buffer: Option<Buffer>,
     capacity: usize,
+    label: Option<String>,
+    label_changed: bool,
 }
 
 impl<T: ShaderType> Default for DynamicUniformBuffer<T> {
@@ -133,6 +155,8 @@ impl<T: ShaderType> Default for DynamicUniformBuffer<T> {
             scratch: DynamicUniformBufferWrapper::new(Vec::new()),
             buffer: None,
             capacity: 0,
+            label: None,
+            label_changed: false,
         }
     }
 }
@@ -170,6 +194,20 @@ impl<T: ShaderType + WriteInto> DynamicUniformBuffer<T> {
         offset
     }
 
+    pub fn set_label(&mut self, label: Option<&str>) {
+        let label = label.map(str::to_string);
+
+        if label != self.label {
+            self.label_changed = true;
+        }
+
+        self.label = label;
+    }
+
+    pub fn get_label(&self) -> Option<&str> {
+        self.label.as_deref()
+    }
+
     /// Queues writing of data from system RAM to VRAM using the [`RenderDevice`](crate::renderer::RenderDevice)
     /// and the provided [`RenderQueue`](crate::renderer::RenderQueue).
     ///
@@ -179,13 +217,14 @@ impl<T: ShaderType + WriteInto> DynamicUniformBuffer<T> {
     pub fn write_buffer(&mut self, device: &RenderDevice, queue: &RenderQueue) {
         let size = self.scratch.as_ref().len();
 
-        if self.capacity < size {
+        if self.capacity < size || self.label_changed {
             self.buffer = Some(device.create_buffer_with_data(&BufferInitDescriptor {
-                label: None,
+                label: self.label.as_deref(),
                 usage: BufferUsages::COPY_DST | BufferUsages::UNIFORM,
                 contents: self.scratch.as_ref(),
             }));
             self.capacity = size;
+            self.label_changed = false;
         } else if let Some(buffer) = &self.buffer {
             queue.write_buffer(buffer, 0, self.scratch.as_ref());
         }