Merge pull request #2351 from iced-rs/custom-renderer-injection

Type-Driven Renderer Fallback

2 files changed, 27 insertions, 8 deletions

diff --git a/widget/src/canvas.rs b/widget/src/canvas.rs
index 0eda0191..7a21895a 100644
--- a/widget/src/canvas.rs
+++ b/widget/src/canvas.rs
@@ -6,8 +6,10 @@ mod program;
 pub use event::Event;
 pub use program::Program;
 
-pub use crate::graphics::geometry::*;
-pub use crate::renderer::geometry::*;
+pub use crate::graphics::geometry::{
+    fill, gradient, path, stroke, Fill, Gradient, LineCap, LineDash, LineJoin,
+    Path, Stroke, Style, Text,
+};
 
 use crate::core;
 use crate::core::layout::{self, Layout};
@@ -21,6 +23,19 @@ use crate::graphics::geometry;
 
 use std::marker::PhantomData;
 
+/// A simple cache that stores generated [`Geometry`] to avoid recomputation.
+///
+/// A [`Cache`] will not redraw its geometry unless the dimensions of its layer
+/// change or it is explicitly cleared.
+pub type Cache<Renderer = crate::Renderer> = geometry::Cache<Renderer>;
+
+/// The geometry supported by a renderer.
+pub type Geometry<Renderer = crate::Renderer> =
+    <Renderer as geometry::Renderer>::Geometry;
+
+/// The frame supported by a renderer.
+pub type Frame<Renderer = crate::Renderer> = geometry::Frame<Renderer>;
+
 /// A widget capable of drawing 2D graphics.
 ///
 /// ## Drawing a simple circle
@@ -42,7 +57,7 @@ use std::marker::PhantomData;
 /// impl Program<()> for Circle {
 ///     type State = ();
 ///
-///     fn draw(&self, _state: &(), renderer: &Renderer, _theme: &Theme, bounds: Rectangle, _cursor: mouse::Cursor) -> Vec<Geometry>{
+///     fn draw(&self, _state: &(), renderer: &Renderer, _theme: &Theme, bounds: Rectangle, _cursor: mouse::Cursor) -> Vec<Geometry> {
 ///         // We prepare a new `Frame`
 ///         let mut frame = Frame::new(renderer, bounds.size());
 ///
@@ -210,9 +225,12 @@ where
         renderer.with_transformation(
             Transformation::translate(bounds.x, bounds.y),
             |renderer| {
-                renderer.draw(
-                    self.program.draw(state, renderer, theme, bounds, cursor),
-                );
+                let layers =
+                    self.program.draw(state, renderer, theme, bounds, cursor);
+
+                for layer in layers {
+                    renderer.draw_geometry(layer);
+                }
             },
         );
     }
diff --git a/widget/src/canvas/program.rs b/widget/src/canvas/program.rs
index 0bff4bda..a7ded0f4 100644
--- a/widget/src/canvas/program.rs
+++ b/widget/src/canvas/program.rs
@@ -1,5 +1,6 @@
 use crate::canvas::event::{self, Event};
 use crate::canvas::mouse;
+use crate::canvas::Geometry;
 use crate::core::Rectangle;
 use crate::graphics::geometry;
 
@@ -52,7 +53,7 @@ where
         theme: &Theme,
         bounds: Rectangle,
         cursor: mouse::Cursor,
-    ) -> Vec<Renderer::Geometry>;
+    ) -> Vec<Geometry<Renderer>>;
 
     /// Returns the current mouse interaction of the [`Program`].
     ///
@@ -94,7 +95,7 @@ where
         theme: &Theme,
         bounds: Rectangle,
         cursor: mouse::Cursor,
-    ) -> Vec<Renderer::Geometry> {
+    ) -> Vec<Geometry<Renderer>> {
         T::draw(self, state, renderer, theme, bounds, cursor)
     }