servo/components/script/dom/canvasrenderingcontext2d.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 canvas_traits::canvas::{Canvas2dMsg, CanvasId, CanvasMsg, FromScriptMsg};
use dom_struct::dom_struct;
use euclid::default::Size2D;
use profile_traits::ipc;
use script_bindings::inheritance::Castable;
use servo_url::ServoUrl;
use snapshot::Snapshot;
use webrender_api::ImageKey;

use crate::canvas_context::{CanvasContext, CanvasHelpers, LayoutCanvasRenderingContextHelpers};
use crate::canvas_state::CanvasState;
use crate::dom::bindings::codegen::Bindings::CanvasRenderingContext2DBinding::{
    CanvasDirection, CanvasFillRule, CanvasImageSource, CanvasLineCap, CanvasLineJoin,
    CanvasRenderingContext2DMethods, CanvasTextAlign, CanvasTextBaseline,
};
use crate::dom::bindings::codegen::UnionTypes::{
    HTMLCanvasElementOrOffscreenCanvas, StringOrCanvasGradientOrCanvasPattern,
};
use crate::dom::bindings::error::{ErrorResult, Fallible};
use crate::dom::bindings::num::Finite;
use crate::dom::bindings::reflector::{DomGlobal, Reflector, reflect_dom_object};
use crate::dom::bindings::root::{DomRoot, LayoutDom};
use crate::dom::bindings::str::DOMString;
use crate::dom::canvasgradient::CanvasGradient;
use crate::dom::canvaspattern::CanvasPattern;
use crate::dom::dommatrix::DOMMatrix;
use crate::dom::globalscope::GlobalScope;
use crate::dom::htmlcanvaselement::HTMLCanvasElement;
use crate::dom::imagedata::ImageData;
use crate::dom::node::{Node, NodeDamage, NodeTraits};
use crate::dom::path2d::Path2D;
use crate::dom::textmetrics::TextMetrics;
use crate::script_runtime::CanGc;

// https://html.spec.whatwg.org/multipage/#canvasrenderingcontext2d
#[dom_struct]
pub(crate) struct CanvasRenderingContext2D {
    reflector_: Reflector,
    canvas: HTMLCanvasElementOrOffscreenCanvas,
    canvas_state: CanvasState,
}

impl CanvasRenderingContext2D {
    pub(crate) fn new_inherited(
        global: &GlobalScope,
        canvas: HTMLCanvasElementOrOffscreenCanvas,
        size: Size2D<u32>,
    ) -> CanvasRenderingContext2D {
        CanvasRenderingContext2D {
            reflector_: Reflector::new(),
            canvas,
            canvas_state: CanvasState::new(
                global,
                Size2D::new(size.width as u64, size.height as u64),
            ),
        }
    }

    pub(crate) fn new(
        global: &GlobalScope,
        canvas: &HTMLCanvasElement,
        size: Size2D<u32>,
        can_gc: CanGc,
    ) -> DomRoot<CanvasRenderingContext2D> {
        let boxed = Box::new(CanvasRenderingContext2D::new_inherited(
            global,
            HTMLCanvasElementOrOffscreenCanvas::HTMLCanvasElement(DomRoot::from_ref(canvas)),
            size,
        ));
        reflect_dom_object(boxed, global, can_gc)
    }

    // https://html.spec.whatwg.org/multipage/#reset-the-rendering-context-to-its-default-state
    fn reset_to_initial_state(&self) {
        self.canvas_state.reset_to_initial_state();
    }

    /// <https://html.spec.whatwg.org/multipage/#concept-canvas-set-bitmap-dimensions>
    pub(crate) fn set_canvas_bitmap_dimensions(&self, size: Size2D<u64>) {
        self.canvas_state.set_bitmap_dimensions(size);
    }

    pub(crate) fn take_missing_image_urls(&self) -> Vec<ServoUrl> {
        std::mem::take(&mut self.canvas_state.get_missing_image_urls().borrow_mut())
    }

    pub(crate) fn get_canvas_id(&self) -> CanvasId {
        self.canvas_state.get_canvas_id()
    }

    pub(crate) fn send_canvas_2d_msg(&self, msg: Canvas2dMsg) {
        self.canvas_state.send_canvas_2d_msg(msg)
    }
}

impl LayoutCanvasRenderingContextHelpers for LayoutDom<'_, CanvasRenderingContext2D> {
    fn canvas_data_source(self) -> Option<ImageKey> {
        let canvas_state = &self.unsafe_get().canvas_state;

        if canvas_state.is_paintable() {
            Some(canvas_state.image_key())
        } else {
            None
        }
    }
}

impl CanvasContext for CanvasRenderingContext2D {
    type ID = CanvasId;

    fn context_id(&self) -> Self::ID {
        self.canvas_state.get_canvas_id()
    }

    fn canvas(&self) -> HTMLCanvasElementOrOffscreenCanvas {
        self.canvas.clone()
    }

    fn update_rendering(&self) {
        self.canvas_state.update_rendering();
    }

    fn resize(&self) {
        self.set_canvas_bitmap_dimensions(self.size().cast())
    }

    fn get_image_data(&self) -> Option<Snapshot> {
        if !self.canvas_state.is_paintable() {
            return None;
        }

        let (sender, receiver) = ipc::channel(self.global().time_profiler_chan().clone()).unwrap();
        let msg = CanvasMsg::FromScript(FromScriptMsg::SendPixels(sender), self.get_canvas_id());
        self.canvas_state.get_ipc_renderer().send(msg).unwrap();

        Some(receiver.recv().unwrap().to_owned())
    }

    fn origin_is_clean(&self) -> bool {
        self.canvas_state.origin_is_clean()
    }

    fn mark_as_dirty(&self) {
        if let Some(canvas) = self.canvas.canvas() {
            canvas.upcast::<Node>().dirty(NodeDamage::OtherNodeDamage);
            canvas.owner_document().add_dirty_2d_canvas(self);
        }
    }
}

// We add a guard to each of methods by the spec:
// http://www.w3.org/html/wg/drafts/2dcontext/html5_canvas_CR/
//
// > Except where otherwise specified, for the 2D context interface,
// > any method call with a numeric argument whose value is infinite or a NaN value must be ignored.
//
//  Restricted values are guarded in glue code. Therefore we need not add a guard.
//
// FIXME: this behavior should might be generated by some annotattions to idl.
impl CanvasRenderingContext2DMethods<crate::DomTypeHolder> for CanvasRenderingContext2D {
    // https://html.spec.whatwg.org/multipage/#dom-context-2d-canvas
    fn Canvas(&self) -> DomRoot<HTMLCanvasElement> {
        match &self.canvas {
            HTMLCanvasElementOrOffscreenCanvas::HTMLCanvasElement(canvas) => canvas.clone(),
            _ => panic!("Should not be called from offscreen canvas"),
        }
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-save
    fn Save(&self) {
        self.canvas_state.save()
    }

    #[cfg_attr(crown, allow(crown::unrooted_must_root))]
    // https://html.spec.whatwg.org/multipage/#dom-context-2d-restore
    fn Restore(&self) {
        self.canvas_state.restore()
    }

    /// <https://html.spec.whatwg.org/multipage/#dom-context-2d-reset>
    fn Reset(&self) {
        self.canvas_state.reset()
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-scale
    fn Scale(&self, x: f64, y: f64) {
        self.canvas_state.scale(x, y)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-rotate
    fn Rotate(&self, angle: f64) {
        self.canvas_state.rotate(angle)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-translate
    fn Translate(&self, x: f64, y: f64) {
        self.canvas_state.translate(x, y)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-transform
    fn Transform(&self, a: f64, b: f64, c: f64, d: f64, e: f64, f: f64) {
        self.canvas_state.transform(a, b, c, d, e, f)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-gettransform
    fn GetTransform(&self, can_gc: CanGc) -> DomRoot<DOMMatrix> {
        self.canvas_state.get_transform(&self.global(), can_gc)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-settransform
    fn SetTransform(&self, a: f64, b: f64, c: f64, d: f64, e: f64, f: f64) {
        self.canvas_state.set_transform(a, b, c, d, e, f)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-resettransform
    fn ResetTransform(&self) {
        self.canvas_state.reset_transform()
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-globalalpha
    fn GlobalAlpha(&self) -> f64 {
        self.canvas_state.global_alpha()
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-globalalpha
    fn SetGlobalAlpha(&self, alpha: f64) {
        self.canvas_state.set_global_alpha(alpha)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-globalcompositeoperation
    fn GlobalCompositeOperation(&self) -> DOMString {
        self.canvas_state.global_composite_operation()
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-globalcompositeoperation
    fn SetGlobalCompositeOperation(&self, op_str: DOMString) {
        self.canvas_state.set_global_composite_operation(op_str)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-fillrect
    fn FillRect(&self, x: f64, y: f64, width: f64, height: f64) {
        self.canvas_state.fill_rect(x, y, width, height);
        self.mark_as_dirty();
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-clearrect
    fn ClearRect(&self, x: f64, y: f64, width: f64, height: f64) {
        self.canvas_state.clear_rect(x, y, width, height);
        self.mark_as_dirty();
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-strokerect
    fn StrokeRect(&self, x: f64, y: f64, width: f64, height: f64) {
        self.canvas_state.stroke_rect(x, y, width, height);
        self.mark_as_dirty();
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-beginpath
    fn BeginPath(&self) {
        self.canvas_state.begin_path()
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-closepath
    fn ClosePath(&self) {
        self.canvas_state.close_path()
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-fill
    fn Fill(&self, fill_rule: CanvasFillRule) {
        self.canvas_state.fill(fill_rule);
        self.mark_as_dirty();
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-fill
    fn Fill_(&self, path: &Path2D, fill_rule: CanvasFillRule) {
        self.canvas_state.fill_(path.segments(), fill_rule);
        self.mark_as_dirty();
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-stroke
    fn Stroke(&self) {
        self.canvas_state.stroke();
        self.mark_as_dirty();
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-stroke
    fn Stroke_(&self, path: &Path2D) {
        self.canvas_state.stroke_(path.segments());
        self.mark_as_dirty();
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-clip
    fn Clip(&self, fill_rule: CanvasFillRule) {
        self.canvas_state.clip(fill_rule)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-clip
    fn Clip_(&self, path: &Path2D, fill_rule: CanvasFillRule) {
        self.canvas_state.clip_(path.segments(), fill_rule)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-ispointinpath
    fn IsPointInPath(&self, x: f64, y: f64, fill_rule: CanvasFillRule) -> bool {
        self.canvas_state
            .is_point_in_path(&self.global(), x, y, fill_rule)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-ispointinpath
    fn IsPointInPath_(&self, path: &Path2D, x: f64, y: f64, fill_rule: CanvasFillRule) -> bool {
        self.canvas_state
            .is_point_in_path_(&self.global(), path.segments(), x, y, fill_rule)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-filltext
    fn FillText(&self, text: DOMString, x: f64, y: f64, max_width: Option<f64>, can_gc: CanGc) {
        self.canvas_state
            .fill_text(self.canvas.canvas(), text, x, y, max_width, can_gc);
        self.mark_as_dirty();
    }

    // https://html.spec.whatwg.org/multipage/#textmetrics
    fn MeasureText(&self, text: DOMString, can_gc: CanGc) -> DomRoot<TextMetrics> {
        self.canvas_state
            .measure_text(&self.global(), self.canvas.canvas(), text, can_gc)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-font
    fn Font(&self) -> DOMString {
        self.canvas_state.font()
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-font
    fn SetFont(&self, value: DOMString, can_gc: CanGc) {
        self.canvas_state
            .set_font(self.canvas.canvas(), value, can_gc)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-textalign
    fn TextAlign(&self) -> CanvasTextAlign {
        self.canvas_state.text_align()
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-textalign
    fn SetTextAlign(&self, value: CanvasTextAlign) {
        self.canvas_state.set_text_align(value)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-textbaseline
    fn TextBaseline(&self) -> CanvasTextBaseline {
        self.canvas_state.text_baseline()
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-textbaseline
    fn SetTextBaseline(&self, value: CanvasTextBaseline) {
        self.canvas_state.set_text_baseline(value)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-direction
    fn Direction(&self) -> CanvasDirection {
        self.canvas_state.direction()
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-direction
    fn SetDirection(&self, value: CanvasDirection) {
        self.canvas_state.set_direction(value)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-drawimage
    fn DrawImage(&self, image: CanvasImageSource, dx: f64, dy: f64) -> ErrorResult {
        self.canvas_state
            .draw_image(self.canvas.canvas(), image, dx, dy)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-drawimage
    fn DrawImage_(
        &self,
        image: CanvasImageSource,
        dx: f64,
        dy: f64,
        dw: f64,
        dh: f64,
    ) -> ErrorResult {
        self.canvas_state
            .draw_image_(self.canvas.canvas(), image, dx, dy, dw, dh)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-drawimage
    fn DrawImage__(
        &self,
        image: CanvasImageSource,
        sx: f64,
        sy: f64,
        sw: f64,
        sh: f64,
        dx: f64,
        dy: f64,
        dw: f64,
        dh: f64,
    ) -> ErrorResult {
        self.canvas_state
            .draw_image__(self.canvas.canvas(), image, sx, sy, sw, sh, dx, dy, dw, dh)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-moveto
    fn MoveTo(&self, x: f64, y: f64) {
        self.canvas_state.move_to(x, y)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-lineto
    fn LineTo(&self, x: f64, y: f64) {
        self.canvas_state.line_to(x, y)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-rect
    fn Rect(&self, x: f64, y: f64, width: f64, height: f64) {
        self.canvas_state.rect(x, y, width, height)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-quadraticcurveto
    fn QuadraticCurveTo(&self, cpx: f64, cpy: f64, x: f64, y: f64) {
        self.canvas_state.quadratic_curve_to(cpx, cpy, x, y)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-beziercurveto
    fn BezierCurveTo(&self, cp1x: f64, cp1y: f64, cp2x: f64, cp2y: f64, x: f64, y: f64) {
        self.canvas_state
            .bezier_curve_to(cp1x, cp1y, cp2x, cp2y, x, y)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-arc
    fn Arc(&self, x: f64, y: f64, r: f64, start: f64, end: f64, ccw: bool) -> ErrorResult {
        self.canvas_state.arc(x, y, r, start, end, ccw)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-arcto
    fn ArcTo(&self, cp1x: f64, cp1y: f64, cp2x: f64, cp2y: f64, r: f64) -> ErrorResult {
        self.canvas_state.arc_to(cp1x, cp1y, cp2x, cp2y, r)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-ellipse
    fn Ellipse(
        &self,
        x: f64,
        y: f64,
        rx: f64,
        ry: f64,
        rotation: f64,
        start: f64,
        end: f64,
        ccw: bool,
    ) -> ErrorResult {
        self.canvas_state
            .ellipse(x, y, rx, ry, rotation, start, end, ccw)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-imagesmoothingenabled
    fn ImageSmoothingEnabled(&self) -> bool {
        self.canvas_state.image_smoothing_enabled()
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-imagesmoothingenabled
    fn SetImageSmoothingEnabled(&self, value: bool) {
        self.canvas_state.set_image_smoothing_enabled(value)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-strokestyle
    fn StrokeStyle(&self) -> StringOrCanvasGradientOrCanvasPattern {
        self.canvas_state.stroke_style()
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-strokestyle
    fn SetStrokeStyle(&self, value: StringOrCanvasGradientOrCanvasPattern, can_gc: CanGc) {
        self.canvas_state
            .set_stroke_style(self.canvas.canvas(), value, can_gc)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-strokestyle
    fn FillStyle(&self) -> StringOrCanvasGradientOrCanvasPattern {
        self.canvas_state.fill_style()
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-strokestyle
    fn SetFillStyle(&self, value: StringOrCanvasGradientOrCanvasPattern, can_gc: CanGc) {
        self.canvas_state
            .set_fill_style(self.canvas.canvas(), value, can_gc)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-createimagedata
    fn CreateImageData(&self, sw: i32, sh: i32, can_gc: CanGc) -> Fallible<DomRoot<ImageData>> {
        self.canvas_state
            .create_image_data(&self.global(), sw, sh, can_gc)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-createimagedata
    fn CreateImageData_(
        &self,
        imagedata: &ImageData,
        can_gc: CanGc,
    ) -> Fallible<DomRoot<ImageData>> {
        self.canvas_state
            .create_image_data_(&self.global(), imagedata, can_gc)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-getimagedata
    fn GetImageData(
        &self,
        sx: i32,
        sy: i32,
        sw: i32,
        sh: i32,
        can_gc: CanGc,
    ) -> Fallible<DomRoot<ImageData>> {
        self.canvas_state
            .get_image_data(self.canvas.size(), &self.global(), sx, sy, sw, sh, can_gc)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-putimagedata
    fn PutImageData(&self, imagedata: &ImageData, dx: i32, dy: i32) {
        self.canvas_state
            .put_image_data(self.canvas.size(), imagedata, dx, dy)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-putimagedata
    #[allow(unsafe_code)]
    fn PutImageData_(
        &self,
        imagedata: &ImageData,
        dx: i32,
        dy: i32,
        dirty_x: i32,
        dirty_y: i32,
        dirty_width: i32,
        dirty_height: i32,
    ) {
        self.canvas_state.put_image_data_(
            self.canvas.size(),
            imagedata,
            dx,
            dy,
            dirty_x,
            dirty_y,
            dirty_width,
            dirty_height,
        );
        self.mark_as_dirty();
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-createlineargradient
    fn CreateLinearGradient(
        &self,
        x0: Finite<f64>,
        y0: Finite<f64>,
        x1: Finite<f64>,
        y1: Finite<f64>,
        can_gc: CanGc,
    ) -> DomRoot<CanvasGradient> {
        self.canvas_state
            .create_linear_gradient(&self.global(), x0, y0, x1, y1, can_gc)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-createradialgradient
    fn CreateRadialGradient(
        &self,
        x0: Finite<f64>,
        y0: Finite<f64>,
        r0: Finite<f64>,
        x1: Finite<f64>,
        y1: Finite<f64>,
        r1: Finite<f64>,
        can_gc: CanGc,
    ) -> Fallible<DomRoot<CanvasGradient>> {
        self.canvas_state
            .create_radial_gradient(&self.global(), x0, y0, r0, x1, y1, r1, can_gc)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-createpattern
    fn CreatePattern(
        &self,
        image: CanvasImageSource,
        repetition: DOMString,
        can_gc: CanGc,
    ) -> Fallible<Option<DomRoot<CanvasPattern>>> {
        self.canvas_state
            .create_pattern(&self.global(), image, repetition, can_gc)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-linewidth
    fn LineWidth(&self) -> f64 {
        self.canvas_state.line_width()
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-linewidth
    fn SetLineWidth(&self, width: f64) {
        self.canvas_state.set_line_width(width)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-linecap
    fn LineCap(&self) -> CanvasLineCap {
        self.canvas_state.line_cap()
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-linecap
    fn SetLineCap(&self, cap: CanvasLineCap) {
        self.canvas_state.set_line_cap(cap)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-linejoin
    fn LineJoin(&self) -> CanvasLineJoin {
        self.canvas_state.line_join()
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-linejoin
    fn SetLineJoin(&self, join: CanvasLineJoin) {
        self.canvas_state.set_line_join(join)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-miterlimit
    fn MiterLimit(&self) -> f64 {
        self.canvas_state.miter_limit()
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-miterlimit
    fn SetMiterLimit(&self, limit: f64) {
        self.canvas_state.set_miter_limit(limit)
    }

    /// <https://html.spec.whatwg.org/multipage/#dom-context-2d-setlinedash>
    fn SetLineDash(&self, segments: Vec<f64>) {
        self.canvas_state.set_line_dash(segments);
    }

    /// <https://html.spec.whatwg.org/multipage/#dom-context-2d-getlinedash>
    fn GetLineDash(&self) -> Vec<f64> {
        self.canvas_state.line_dash()
    }

    /// <https://html.spec.whatwg.org/multipage/#dom-context-2d-linedashoffset>
    fn LineDashOffset(&self) -> f64 {
        self.canvas_state.line_dash_offset()
    }

    /// <https://html.spec.whatwg.org/multipage/#dom-context-2d-linedashoffset>
    fn SetLineDashOffset(&self, offset: f64) {
        self.canvas_state.set_line_dash_offset(offset);
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-shadowoffsetx
    fn ShadowOffsetX(&self) -> f64 {
        self.canvas_state.shadow_offset_x()
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-shadowoffsetx
    fn SetShadowOffsetX(&self, value: f64) {
        self.canvas_state.set_shadow_offset_x(value)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-shadowoffsety
    fn ShadowOffsetY(&self) -> f64 {
        self.canvas_state.shadow_offset_y()
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-shadowoffsety
    fn SetShadowOffsetY(&self, value: f64) {
        self.canvas_state.set_shadow_offset_y(value)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-shadowblur
    fn ShadowBlur(&self) -> f64 {
        self.canvas_state.shadow_blur()
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-shadowblur
    fn SetShadowBlur(&self, value: f64) {
        self.canvas_state.set_shadow_blur(value)
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-shadowcolor
    fn ShadowColor(&self) -> DOMString {
        self.canvas_state.shadow_color()
    }

    // https://html.spec.whatwg.org/multipage/#dom-context-2d-shadowcolor
    fn SetShadowColor(&self, value: DOMString, can_gc: CanGc) {
        self.canvas_state
            .set_shadow_color(self.canvas.canvas(), value, can_gc)
    }
}

impl Drop for CanvasRenderingContext2D {
    fn drop(&mut self) {
        if let Err(err) = self
            .canvas_state
            .get_ipc_renderer()
            .send(CanvasMsg::Close(self.canvas_state.get_canvas_id()))
        {
            warn!("Could not close canvas: {}", err)
        }
    }
}