servo/components/script/dom/gpucommandencoder.rs

/* 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::GPUBufferBinding::GPUSize64;
use crate::dom::bindings::codegen::Bindings::GPUCommandEncoderBinding::{
    GPUBufferCopyView, GPUCommandBufferDescriptor, GPUCommandEncoderMethods,
    GPUComputePassDescriptor, GPUOrigin3D, GPURenderPassDescriptor, GPUStencilLoadValue,
    GPUStoreOp, GPUTextureCopyView, GPUTextureDataLayout,
};
use crate::dom::bindings::codegen::Bindings::GPUTextureBinding::GPUExtent3D;
use crate::dom::bindings::codegen::UnionTypes::{
    GPULoadOpOrDoubleSequenceOrGPUColorDict as GPUColorLoad, GPULoadOpOrFloat,
};
use crate::dom::bindings::num::Finite;
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::USVString;
use crate::dom::globalscope::GlobalScope;
use crate::dom::gpubuffer::GPUBuffer;
use crate::dom::gpucommandbuffer::GPUCommandBuffer;
use crate::dom::gpucomputepassencoder::GPUComputePassEncoder;
use crate::dom::gpudevice::{convert_texture_size_to_dict, convert_texture_size_to_wgt};
use crate::dom::gpurenderpassencoder::GPURenderPassEncoder;
use dom_struct::dom_struct;
use std::borrow::Cow;
use std::cell::Cell;
use std::collections::HashSet;
use webgpu::wgpu::command as wgpu_com;
use webgpu::{self, wgt, WebGPU, WebGPUDevice, WebGPURequest};

// https://gpuweb.github.io/gpuweb/#enumdef-encoder-state
#[derive(MallocSizeOf, PartialEq)]
pub enum GPUCommandEncoderState {
    Open,
    EncodingRenderPass,
    EncodingComputePass,
    Closed,
}

#[dom_struct]
pub struct GPUCommandEncoder {
    reflector_: Reflector,
    #[ignore_malloc_size_of = "defined in webgpu"]
    channel: WebGPU,
    label: DomRefCell<Option<USVString>>,
    encoder: webgpu::WebGPUCommandEncoder,
    buffers: DomRefCell<HashSet<DomRoot<GPUBuffer>>>,
    state: DomRefCell<GPUCommandEncoderState>,
    device: WebGPUDevice,
    valid: Cell<bool>,
}

impl GPUCommandEncoder {
    pub fn new_inherited(
        channel: WebGPU,
        device: WebGPUDevice,
        encoder: webgpu::WebGPUCommandEncoder,
        valid: bool,
        label: Option<USVString>,
    ) -> Self {
        Self {
            channel,
            reflector_: Reflector::new(),
            label: DomRefCell::new(label),
            device,
            encoder,
            buffers: DomRefCell::new(HashSet::new()),
            state: DomRefCell::new(GPUCommandEncoderState::Open),
            valid: Cell::new(valid),
        }
    }

    pub fn new(
        global: &GlobalScope,
        channel: WebGPU,
        device: WebGPUDevice,
        encoder: webgpu::WebGPUCommandEncoder,
        valid: bool,
        label: Option<USVString>,
    ) -> DomRoot<Self> {
        reflect_dom_object(
            Box::new(GPUCommandEncoder::new_inherited(
                channel, device, encoder, valid, label,
            )),
            global,
        )
    }
}

impl GPUCommandEncoder {
    pub fn id(&self) -> webgpu::WebGPUCommandEncoder {
        self.encoder
    }

    pub fn set_state(&self, set: GPUCommandEncoderState, expect: GPUCommandEncoderState) {
        if *self.state.borrow() == expect {
            *self.state.borrow_mut() = set;
        } else {
            self.valid.set(false);
            *self.state.borrow_mut() = GPUCommandEncoderState::Closed;
        }
    }
}

impl GPUCommandEncoderMethods for GPUCommandEncoder {
    /// https://gpuweb.github.io/gpuweb/#dom-gpuobjectbase-label
    fn GetLabel(&self) -> Option<USVString> {
        self.label.borrow().clone()
    }

    /// https://gpuweb.github.io/gpuweb/#dom-gpuobjectbase-label
    fn SetLabel(&self, value: Option<USVString>) {
        *self.label.borrow_mut() = value;
    }

    /// https://gpuweb.github.io/gpuweb/#dom-gpucommandencoder-begincomputepass
    fn BeginComputePass(
        &self,
        descriptor: &GPUComputePassDescriptor,
    ) -> DomRoot<GPUComputePassEncoder> {
        self.set_state(
            GPUCommandEncoderState::EncodingComputePass,
            GPUCommandEncoderState::Open,
        );
        GPUComputePassEncoder::new(
            &self.global(),
            self.channel.clone(),
            &self,
            descriptor.parent.label.as_ref().cloned(),
        )
    }

    /// https://gpuweb.github.io/gpuweb/#dom-gpucommandencoder-beginrenderpass
    fn BeginRenderPass(
        &self,
        descriptor: &GPURenderPassDescriptor,
    ) -> DomRoot<GPURenderPassEncoder> {
        self.set_state(
            GPUCommandEncoderState::EncodingRenderPass,
            GPUCommandEncoderState::Open,
        );

        let depth_stencil = descriptor.depthStencilAttachment.as_ref().map(|depth| {
            let (depth_load_op, clear_depth) = match depth.depthLoadValue {
                GPULoadOpOrFloat::GPULoadOp(_) => (wgpu_com::LoadOp::Load, 0.0f32),
                GPULoadOpOrFloat::Float(f) => (wgpu_com::LoadOp::Clear, *f),
            };
            let (stencil_load_op, clear_stencil) = match depth.stencilLoadValue {
                GPUStencilLoadValue::GPULoadOp(_) => (wgpu_com::LoadOp::Load, 0u32),
                GPUStencilLoadValue::RangeEnforcedUnsignedLong(l) => (wgpu_com::LoadOp::Clear, l),
            };
            let depth_channel = wgpu_com::PassChannel {
                load_op: depth_load_op,
                store_op: match depth.depthStoreOp {
                    GPUStoreOp::Store => wgpu_com::StoreOp::Store,
                    GPUStoreOp::Clear => wgpu_com::StoreOp::Clear,
                },
                clear_value: clear_depth,
                read_only: depth.depthReadOnly,
            };
            let stencil_channel = wgpu_com::PassChannel {
                load_op: stencil_load_op,
                store_op: match depth.stencilStoreOp {
                    GPUStoreOp::Store => wgpu_com::StoreOp::Store,
                    GPUStoreOp::Clear => wgpu_com::StoreOp::Clear,
                },
                clear_value: clear_stencil,
                read_only: depth.stencilReadOnly,
            };
            wgpu_com::DepthStencilAttachmentDescriptor {
                attachment: depth.attachment.id().0,
                depth: depth_channel,
                stencil: stencil_channel,
            }
        });

        let desc = wgpu_com::RenderPassDescriptor {
            color_attachments: Cow::Owned(
                descriptor
                    .colorAttachments
                    .iter()
                    .map(|color| {
                        let (load_op, clear_value) = match color.loadValue {
                            GPUColorLoad::GPULoadOp(_) => {
                                (wgpu_com::LoadOp::Load, wgt::Color::TRANSPARENT)
                            },
                            GPUColorLoad::DoubleSequence(ref s) => {
                                let mut w = s.clone();
                                if w.len() < 3 {
                                    w.resize(3, Finite::wrap(0.0f64));
                                }
                                w.resize(4, Finite::wrap(1.0f64));
                                (
                                    wgpu_com::LoadOp::Clear,
                                    wgt::Color {
                                        r: *w[0],
                                        g: *w[1],
                                        b: *w[2],
                                        a: *w[3],
                                    },
                                )
                            },
                            GPUColorLoad::GPUColorDict(ref d) => (
                                wgpu_com::LoadOp::Clear,
                                wgt::Color {
                                    r: *d.r,
                                    g: *d.g,
                                    b: *d.b,
                                    a: *d.a,
                                },
                            ),
                        };
                        let channel = wgpu_com::PassChannel {
                            load_op,
                            store_op: match color.storeOp {
                                GPUStoreOp::Store => wgpu_com::StoreOp::Store,
                                GPUStoreOp::Clear => wgpu_com::StoreOp::Clear,
                            },
                            clear_value,
                            read_only: false,
                        };
                        wgpu_com::ColorAttachmentDescriptor {
                            attachment: color.attachment.id().0,
                            resolve_target: color.resolveTarget.as_ref().map(|t| t.id().0),
                            channel,
                        }
                    })
                    .collect::<Vec<_>>(),
            ),
            depth_stencil_attachment: depth_stencil.as_ref(),
        };

        let render_pass = wgpu_com::RenderPass::new(self.encoder.0, desc);

        GPURenderPassEncoder::new(
            &self.global(),
            self.channel.clone(),
            render_pass,
            &self,
            descriptor.parent.label.as_ref().cloned(),
        )
    }

    /// https://gpuweb.github.io/gpuweb/#dom-gpucommandencoder-copybuffertobuffer
    fn CopyBufferToBuffer(
        &self,
        source: &GPUBuffer,
        source_offset: GPUSize64,
        destination: &GPUBuffer,
        destination_offset: GPUSize64,
        size: GPUSize64,
    ) {
        let valid = *self.state.borrow() == GPUCommandEncoderState::Open;

        if !valid {
            // TODO: Record an error in the current scope.
            self.valid.set(false);
            return;
        }

        self.buffers.borrow_mut().insert(DomRoot::from_ref(source));
        self.buffers
            .borrow_mut()
            .insert(DomRoot::from_ref(destination));
        self.channel
            .0
            .send(WebGPURequest::CopyBufferToBuffer {
                command_encoder_id: self.encoder.0,
                source_id: source.id().0,
                source_offset,
                destination_id: destination.id().0,
                destination_offset,
                size,
            })
            .expect("Failed to send CopyBufferToBuffer");
    }

    /// https://gpuweb.github.io/gpuweb/#dom-gpucommandencoder-copybuffertotexture
    fn CopyBufferToTexture(
        &self,
        source: &GPUBufferCopyView,
        destination: &GPUTextureCopyView,
        copy_size: GPUExtent3D,
    ) {
        let valid = *self.state.borrow() == GPUCommandEncoderState::Open;

        if !valid {
            // TODO: Record an error in the current scope.
            self.valid.set(false);
            return;
        }

        self.buffers
            .borrow_mut()
            .insert(DomRoot::from_ref(&*source.buffer));

        self.channel
            .0
            .send(WebGPURequest::CopyBufferToTexture {
                command_encoder_id: self.encoder.0,
                source: convert_buffer_cv(source),
                destination: convert_texture_cv(destination),
                copy_size: convert_texture_size_to_wgt(&convert_texture_size_to_dict(&copy_size)),
            })
            .expect("Failed to send CopyBufferToTexture");
    }

    /// https://gpuweb.github.io/gpuweb/#GPUCommandEncoder-copyTextureToBuffer
    fn CopyTextureToBuffer(
        &self,
        source: &GPUTextureCopyView,
        destination: &GPUBufferCopyView,
        copy_size: GPUExtent3D,
    ) {
        let valid = *self.state.borrow() == GPUCommandEncoderState::Open;

        if !valid {
            // TODO: Record an error in the current scope.
            self.valid.set(false);
            return;
        }

        self.buffers
            .borrow_mut()
            .insert(DomRoot::from_ref(&*destination.buffer));

        self.channel
            .0
            .send(WebGPURequest::CopyTextureToBuffer {
                command_encoder_id: self.encoder.0,
                source: convert_texture_cv(source),
                destination: convert_buffer_cv(destination),
                copy_size: convert_texture_size_to_wgt(&convert_texture_size_to_dict(&copy_size)),
            })
            .expect("Failed to send CopyTextureToBuffer");
    }

    /// https://gpuweb.github.io/gpuweb/#GPUCommandEncoder-copyTextureToTexture
    fn CopyTextureToTexture(
        &self,
        source: &GPUTextureCopyView,
        destination: &GPUTextureCopyView,
        copy_size: GPUExtent3D,
    ) {
        let valid = *self.state.borrow() == GPUCommandEncoderState::Open;

        if !valid {
            // TODO: Record an error in the current scope.
            self.valid.set(false);
            return;
        }

        self.channel
            .0
            .send(WebGPURequest::CopyTextureToTexture {
                command_encoder_id: self.encoder.0,
                source: convert_texture_cv(source),
                destination: convert_texture_cv(destination),
                copy_size: convert_texture_size_to_wgt(&convert_texture_size_to_dict(&copy_size)),
            })
            .expect("Failed to send CopyTextureToTexture");
    }

    /// https://gpuweb.github.io/gpuweb/#dom-gpucommandencoder-finish
    fn Finish(&self, descriptor: &GPUCommandBufferDescriptor) -> DomRoot<GPUCommandBuffer> {
        self.channel
            .0
            .send(WebGPURequest::CommandEncoderFinish {
                command_encoder_id: 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 Finish");

        *self.state.borrow_mut() = GPUCommandEncoderState::Closed;
        let buffer = webgpu::WebGPUCommandBuffer(self.encoder.0);
        GPUCommandBuffer::new(
            &self.global(),
            self.channel.clone(),
            buffer,
            self.buffers.borrow_mut().drain().collect(),
            descriptor.parent.label.as_ref().cloned(),
        )
    }
}

fn convert_buffer_cv(buffer_cv: &GPUBufferCopyView) -> wgpu_com::BufferCopyView {
    wgpu_com::BufferCopyView {
        buffer: buffer_cv.buffer.id().0,
        layout: convert_texture_data_layout(&buffer_cv.parent),
    }
}

pub fn convert_texture_cv(texture_cv: &GPUTextureCopyView) -> wgpu_com::TextureCopyView {
    wgpu_com::TextureCopyView {
        texture: texture_cv.texture.id().0,
        mip_level: texture_cv.mipLevel,
        origin: match texture_cv.origin {
            GPUOrigin3D::RangeEnforcedUnsignedLongSequence(ref v) => {
                let mut w = v.clone();
                w.resize(3, 0);
                wgt::Origin3d {
                    x: w[0],
                    y: w[1],
                    z: w[2],
                }
            },
            GPUOrigin3D::GPUOrigin3DDict(ref d) => wgt::Origin3d {
                x: d.x,
                y: d.y,
                z: d.z,
            },
        },
    }
}

pub fn convert_texture_data_layout(data_layout: &GPUTextureDataLayout) -> wgt::TextureDataLayout {
    wgt::TextureDataLayout {
        offset: data_layout.offset as wgt::BufferAddress,
        bytes_per_row: data_layout.bytesPerRow,
        rows_per_image: data_layout.rowsPerImage,
    }
}