Added support for gradients to respect current frame transform.

4 files changed, 43 insertions, 19 deletions

diff --git a/graphics/src/widget/canvas.rs b/graphics/src/widget/canvas.rs
index 4a2c5b2d..fe0f618f 100644
--- a/graphics/src/widget/canvas.rs
+++ b/graphics/src/widget/canvas.rs
@@ -9,12 +9,12 @@ pub mod path;
 
 mod cache;
 mod cursor;
-mod frame;
 mod geometry;
 mod program;
 mod text;
 pub mod fill;
 pub mod stroke;
+pub(crate) mod frame;
 
 pub use cache::Cache;
 pub use cursor::Cursor;
diff --git a/graphics/src/widget/canvas/fill.rs b/graphics/src/widget/canvas/fill.rs
index 55cb3966..768c2b9c 100644
--- a/graphics/src/widget/canvas/fill.rs
+++ b/graphics/src/widget/canvas/fill.rs
@@ -3,6 +3,7 @@
 use crate::gradient::Gradient;
 use crate::layer::mesh;
 use iced_native::Color;
+use crate::widget::canvas::frame::Transform;
 
 /// The style used to fill geometry.
 #[derive(Debug, Clone)]
@@ -50,11 +51,16 @@ pub enum Style<'a> {
     Gradient(&'a Gradient),
 }
 
-impl<'a> Into<mesh::Style> for Style<'a> {
-    fn into(self) -> mesh::Style {
+impl<'a> Style<'a> {
+    /// Converts a fill's [Style] to a [mesh::Style] for use in the renderer's shader.
+    pub(crate) fn as_mesh_style(&self, transform: &Transform) -> mesh::Style {
         match self {
-            Style::Solid(color) => mesh::Style::Solid(color),
-            Style::Gradient(gradient) => gradient.clone().into(),
+            Style::Solid(color) => {
+                mesh::Style::Solid(*color)
+            },
+            Style::Gradient(gradient) => {
+                mesh::Style::Gradient((*gradient).clone().transform(transform))
+            }
         }
     }
 }
diff --git a/graphics/src/widget/canvas/frame.rs b/graphics/src/widget/canvas/frame.rs
index 427a2e2a..ccba840a 100644
--- a/graphics/src/widget/canvas/frame.rs
+++ b/graphics/src/widget/canvas/frame.rs
@@ -1,3 +1,4 @@
+use lyon::geom::euclid::Vector2D;
 use std::borrow::Cow;
 
 use iced_native::{Point, Rectangle, Size, Vector};
@@ -30,11 +31,22 @@ struct Transforms {
 }
 
 #[derive(Debug, Clone, Copy)]
-struct Transform {
+pub(crate) struct Transform {
     raw: lyon::math::Transform,
     is_identity: bool,
 }
 
+impl Transform {
+    /// Transforms the given [Point] by the transformation matrix.
+    pub(crate) fn apply_to(&self, mut point: Point) -> Point {
+        let transformed =
+            self.raw.transform_vector(Vector2D::new(point.x, point.y));
+        point.x = transformed.x + self.raw.m31;
+        point.y = transformed.y + self.raw.m32;
+        point
+    }
+}
+
 impl Frame {
     /// Creates a new empty [`Frame`] with the given dimensions.
     ///
@@ -111,7 +123,8 @@ impl Frame {
         }
         .expect("Tessellate path.");
 
-        self.buffers.push((buf, style.into()))
+        self.buffers
+            .push((buf, style.as_mesh_style(&self.transforms.current)));
     }
 
     /// Draws an axis-aligned rectangle given its top-left corner coordinate and
@@ -150,7 +163,8 @@ impl Frame {
             )
             .expect("Fill rectangle");
 
-        self.buffers.push((buf, style.into()))
+        self.buffers
+            .push((buf, style.as_mesh_style(&self.transforms.current)));
     }
 
     /// Draws the stroke of the given [`Path`] on the [`Frame`] with the
@@ -192,7 +206,8 @@ impl Frame {
         }
         .expect("Stroke path");
 
-        self.buffers.push((buf, stroke.style.into()))
+        self.buffers
+            .push((buf, stroke.style.as_mesh_style(&self.transforms.current)))
     }
 
     /// Draws the characters of the given [`Text`] on the [`Frame`], filling
@@ -307,7 +322,7 @@ impl Frame {
         self.transforms.current.is_identity = false;
     }
 
-    /// Applies a rotation to the current transform of the [`Frame`].
+    /// Applies a rotation in radians to the current transform of the [`Frame`].
     #[inline]
     pub fn rotate(&mut self, angle: f32) {
         self.transforms.current.raw = self
@@ -354,10 +369,7 @@ impl Frame {
 struct Vertex2DBuilder;
 
 impl tessellation::FillVertexConstructor<Vertex2D> for Vertex2DBuilder {
-    fn new_vertex(
-        &mut self,
-        vertex: tessellation::FillVertex<'_>,
-    ) -> Vertex2D {
+    fn new_vertex(&mut self, vertex: tessellation::FillVertex<'_>) -> Vertex2D {
         let position = vertex.position();
 
         Vertex2D {
@@ -377,4 +389,4 @@ impl tessellation::StrokeVertexConstructor<Vertex2D> for Vertex2DBuilder {
             position: [position.x, position.y],
         }
     }
-}
\ No newline at end of file
+}
diff --git a/graphics/src/widget/canvas/stroke.rs b/graphics/src/widget/canvas/stroke.rs
index a19937ea..aaac15bb 100644
--- a/graphics/src/widget/canvas/stroke.rs
+++ b/graphics/src/widget/canvas/stroke.rs
@@ -3,6 +3,7 @@
 use iced_native::Color;
 use crate::gradient::Gradient;
 use crate::layer::mesh;
+use crate::widget::canvas::frame::Transform;
 
 /// The style of a stroke.
 #[derive(Debug, Clone)]
@@ -68,11 +69,16 @@ pub enum Style<'a> {
     Gradient(&'a Gradient),
 }
 
-impl <'a> Into<mesh::Style> for Style<'a> {
-    fn into(self) -> mesh::Style {
+impl<'a> Style<'a> {
+    /// Converts a fill's [Style] to a [mesh::Style] for use in the renderer's shader.
+    pub(crate) fn as_mesh_style(&self, transform: &Transform) -> mesh::Style {
         match self {
-            Style::Solid(color) => mesh::Style::Solid(color),
-            Style::Gradient(gradient) => gradient.clone().into()
+            Style::Solid(color) => {
+                mesh::Style::Solid(*color)
+            },
+            Style::Gradient(gradient) => {
+                mesh::Style::Gradient((*gradient).clone().transform(transform))
+            }
         }
     }
 }