Auto merge of #25734 - pylbrecht:get.transform, r=jdm

Implement CanvasRenderingContext2D.getTransform()

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- [x] These changes fix part of #25331

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- [x] There are tests for these changes

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1 files changed, 10 insertions, 0 deletions

diff --git a/components/script/canvas_state.rs b/components/script/canvas_state.rs
index d596ff826fa..41c92fc0799 100644
--- a/components/script/canvas_state.rs
+++ b/components/script/canvas_state.rs
@@ -16,6 +16,7 @@ use crate::dom::bindings::root::{Dom, DomRoot};
 use crate::dom::bindings::str::DOMString;
 use crate::dom::canvasgradient::{CanvasGradient, CanvasGradientStyle, ToFillOrStrokeStyle};
 use crate::dom::canvaspattern::CanvasPattern;
+use crate::dom::dommatrix::DOMMatrix;
 use crate::dom::element::cors_setting_for_element;
 use crate::dom::element::Element;
 use crate::dom::globalscope::GlobalScope;
@@ -1415,6 +1416,15 @@ impl CanvasState {
         self.update_transform()
     }
 
+    // https://html.spec.whatwg.org/multipage/#dom-context-2d-gettransform
+    pub fn get_transform(&self, global: &GlobalScope) -> DomRoot<DOMMatrix> {
+        let (sender, receiver) = ipc::channel::<Transform2D<f32>>().unwrap();
+        self.send_canvas_2d_msg(Canvas2dMsg::GetTransform(sender));
+        let transform = receiver.recv().unwrap();
+
+        DOMMatrix::new(global, true, transform.cast::<f64>().to_3d())
+    }
+
     // https://html.spec.whatwg.org/multipage/#dom-context-2d-settransform
     pub fn set_transform(&self, a: f64, b: f64, c: f64, d: f64, e: f64, f: f64) {
         if !(a.is_finite() &&