Auto merge of #25702 - szeged:wgpu_command_encoder, r=jdm

Initial implementation of GPUCommandEncoder

<!-- Please describe your changes on the following line: -->
Added WebIDL bindings for `GPUCommandEncoder`, `GPUCommandBuffer`, `GPUComputePassEncoder` and `GPUProgrammablePassEncoder`.
Implemented the `beginComputePass`, `copyBufferToBuffer` and `finish` functions of `GPUCommandEncoder`.
Implemented the `createCommandEncoder` function of `GPUDevice`.
This pull request is based on: #25700

---
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes addresses a part of #24706

cc @kvark @jdm @zakorgy
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1 files changed, 114 insertions, 0 deletions

diff --git a/components/script/dom/gpucommandencoder.rs b/components/script/dom/gpucommandencoder.rs
new file mode 100644
index 00000000000..5e86c0b8bfd
--- /dev/null
+++ b/components/script/dom/gpucommandencoder.rs
@@ -0,0 +1,114 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+use crate::dom::bindings::cell::DomRefCell;
+use crate::dom::bindings::codegen::Bindings::GPUCommandEncoderBinding::{
+    self, GPUCommandBufferDescriptor, GPUCommandEncoderMethods, GPUComputePassDescriptor,
+};
+use crate::dom::bindings::reflector::DomObject;
+use crate::dom::bindings::reflector::{reflect_dom_object, Reflector};
+use crate::dom::bindings::root::DomRoot;
+use crate::dom::bindings::str::DOMString;
+use crate::dom::globalscope::GlobalScope;
+use crate::dom::gpubuffer::GPUBuffer;
+use crate::dom::gpucommandbuffer::GPUCommandBuffer;
+use crate::dom::gpucomputepassencoder::GPUComputePassEncoder;
+use dom_struct::dom_struct;
+use ipc_channel::ipc;
+use webgpu::{wgpu::command::RawPass, WebGPU, WebGPUCommandEncoder, WebGPURequest};
+
+#[dom_struct]
+pub struct GPUCommandEncoder {
+    reflector_: Reflector,
+    #[ignore_malloc_size_of = "defined in webgpu"]
+    channel: WebGPU,
+    label: DomRefCell<Option<DOMString>>,
+    encoder: WebGPUCommandEncoder,
+}
+
+impl GPUCommandEncoder {
+    pub fn new_inherited(channel: WebGPU, encoder: WebGPUCommandEncoder) -> GPUCommandEncoder {
+        GPUCommandEncoder {
+            channel,
+            reflector_: Reflector::new(),
+            label: DomRefCell::new(None),
+            encoder,
+        }
+    }
+
+    pub fn new(
+        global: &GlobalScope,
+        channel: WebGPU,
+        encoder: WebGPUCommandEncoder,
+    ) -> DomRoot<GPUCommandEncoder> {
+        reflect_dom_object(
+            Box::new(GPUCommandEncoder::new_inherited(channel, encoder)),
+            global,
+            GPUCommandEncoderBinding::Wrap,
+        )
+    }
+}
+
+impl GPUCommandEncoderMethods for GPUCommandEncoder {
+    /// https://gpuweb.github.io/gpuweb/#dom-gpuobjectbase-label
+    fn GetLabel(&self) -> Option<DOMString> {
+        self.label.borrow().clone()
+    }
+
+    /// https://gpuweb.github.io/gpuweb/#dom-gpuobjectbase-label
+    fn SetLabel(&self, value: Option<DOMString>) {
+        *self.label.borrow_mut() = value;
+    }
+
+    /// https://gpuweb.github.io/gpuweb/#dom-gpucommandencoder-begincomputepass
+    fn BeginComputePass(
+        &self,
+        _descriptor: &GPUComputePassDescriptor,
+    ) -> DomRoot<GPUComputePassEncoder> {
+        GPUComputePassEncoder::new(
+            &self.global(),
+            self.channel.clone(),
+            RawPass::new_compute(self.encoder.0),
+        )
+    }
+
+    /// https://gpuweb.github.io/gpuweb/#dom-gpucommandencoder-copybuffertobuffer
+    fn CopyBufferToBuffer(
+        &self,
+        source: &GPUBuffer,
+        source_offset: u64,
+        destination: &GPUBuffer,
+        destination_offset: u64,
+        size: u64,
+    ) {
+        self.channel
+            .0
+            .send(WebGPURequest::CopyBufferToBuffer(
+                self.encoder.0,
+                source.id().0,
+                source_offset,
+                destination.id().0,
+                destination_offset,
+                size,
+            ))
+            .expect("Failed to send CopyBufferToBuffer");
+    }
+
+    /// https://gpuweb.github.io/gpuweb/#dom-gpucommandencoder-finish
+    fn Finish(&self, _descriptor: &GPUCommandBufferDescriptor) -> DomRoot<GPUCommandBuffer> {
+        let (sender, receiver) = ipc::channel().unwrap();
+        self.channel
+            .0
+            .send(WebGPURequest::CommandEncoderFinish(
+                sender,
+                self.encoder.0,
+                // TODO(zakorgy): We should use `_descriptor` here after it's not empty
+                // and the underlying wgpu-core struct is serializable
+            ))
+            .expect("Failed to send CopyBufferToBuffer");
+
+        let buffer = receiver.recv().unwrap();
+        GPUCommandBuffer::new(&self.global(), self.channel.clone(), buffer)
+    }
+}