Implement `Frame::fill` and `Frame::stroke`

1 files changed, 74 insertions, 2 deletions

diff --git a/wgpu/src/widget/canvas/frame.rs b/wgpu/src/widget/canvas/frame.rs
index e5daeedb..82ff526b 100644
--- a/wgpu/src/widget/canvas/frame.rs
+++ b/wgpu/src/widget/canvas/frame.rs
@@ -33,7 +33,79 @@ impl Frame {
         Point::new(self.width as f32 / 2.0, self.height as f32 / 2.0)
     }
 
-    pub fn fill(&mut self, path: &Path, fill: Fill) {}
+    pub fn fill(&mut self, path: &Path, fill: Fill) {
+        use lyon::tessellation::{
+            BuffersBuilder, FillOptions, FillTessellator,
+        };
 
-    pub fn stroke(&mut self, path: &Path, stroke: Stroke) {}
+        let mut buffers = BuffersBuilder::new(
+            &mut self.buffers,
+            FillVertex(match fill {
+                Fill::Color(color) => color.into_linear(),
+            }),
+        );
+
+        let mut tessellator = FillTessellator::new();
+
+        let _ = tessellator
+            .tessellate_path(path.raw(), &FillOptions::default(), &mut buffers)
+            .expect("Tessellate path");
+    }
+
+    pub fn stroke(&mut self, path: &Path, stroke: Stroke) {
+        use lyon::tessellation::{
+            BuffersBuilder, StrokeOptions, StrokeTessellator,
+        };
+
+        let mut buffers = BuffersBuilder::new(
+            &mut self.buffers,
+            StrokeVertex(stroke.color.into_linear()),
+        );
+
+        let mut tessellator = StrokeTessellator::new();
+
+        let mut options = StrokeOptions::default();
+        options.line_width = stroke.width;
+        options.start_cap = stroke.line_cap.into();
+        options.end_cap = stroke.line_cap.into();
+        options.line_join = stroke.line_join.into();
+
+        let _ = tessellator
+            .tessellate_path(path.raw(), &options, &mut buffers)
+            .expect("Stroke path");
+    }
+}
+
+struct FillVertex([f32; 4]);
+
+impl lyon::tessellation::FillVertexConstructor<triangle::Vertex2D>
+    for FillVertex
+{
+    fn new_vertex(
+        &mut self,
+        position: lyon::math::Point,
+        _attributes: lyon::tessellation::FillAttributes<'_>,
+    ) -> triangle::Vertex2D {
+        triangle::Vertex2D {
+            position: [position.x, position.y],
+            color: self.0,
+        }
+    }
+}
+
+struct StrokeVertex([f32; 4]);
+
+impl lyon::tessellation::StrokeVertexConstructor<triangle::Vertex2D>
+    for StrokeVertex
+{
+    fn new_vertex(
+        &mut self,
+        position: lyon::math::Point,
+        _attributes: lyon::tessellation::StrokeAttributes<'_, '_>,
+    ) -> triangle::Vertex2D {
+        triangle::Vertex2D {
+            position: [position.x, position.y],
+            color: self.0,
+        }
+    }
 }