Introduce `Translate` primitive in `iced_wgpu`

8 files changed, 64 insertions, 45 deletions

diff --git a/wgpu/src/primitive.rs b/wgpu/src/primitive.rs
index 46d9e624..e9c0bf46 100644
--- a/wgpu/src/primitive.rs
+++ b/wgpu/src/primitive.rs
@@ -1,5 +1,5 @@
 use iced_native::{
-    image, svg, Background, Color, Font, HorizontalAlignment, Point, Rectangle,
+    image, svg, Background, Color, Font, HorizontalAlignment, Rectangle,
     Vector, VerticalAlignment,
 };
 
@@ -70,13 +70,18 @@ pub enum Primitive {
         /// The content of the clip
         content: Box<Primitive>,
     },
+    /// A primitive that applies a translation
+    Translate {
+        /// The top-left coordinate of the mesh
+        translation: Vector,
+
+        /// The primitive to translate
+        content: Box<Primitive>,
+    },
     /// A low-level primitive to render a mesh of triangles.
     ///
     /// It can be used to render many kinds of geometry freely.
     Mesh2D {
-        /// The top-left coordinate of the mesh
-        origin: Point,
-
         /// The vertex and index buffers of the mesh
         buffers: triangle::Mesh2D,
     },
@@ -85,9 +90,6 @@ pub enum Primitive {
     /// This can be useful if you are implementing a widget where primitive
     /// generation is expensive.
     Cached {
-        /// The origin of the coordinate system of the cached primitives
-        origin: Point,
-
         /// The cached primitive
         cache: Arc<Primitive>,
     },
diff --git a/wgpu/src/renderer.rs b/wgpu/src/renderer.rs
index 481b310c..e93532bc 100644
--- a/wgpu/src/renderer.rs
+++ b/wgpu/src/renderer.rs
@@ -29,7 +29,7 @@ pub struct Renderer {
 struct Layer<'a> {
     bounds: Rectangle<u32>,
     quads: Vec<Quad>,
-    meshes: Vec<(Point, &'a triangle::Mesh2D)>,
+    meshes: Vec<(Vector, &'a triangle::Mesh2D)>,
     text: Vec<wgpu_glyph::Section<'a>>,
 
     #[cfg(any(feature = "image", feature = "svg"))]
@@ -214,10 +214,10 @@ impl Renderer {
                     border_color: border_color.into_linear(),
                 });
             }
-            Primitive::Mesh2D { origin, buffers } => {
+            Primitive::Mesh2D { buffers } => {
                 let layer = layers.last_mut().unwrap();
 
-                layer.meshes.push((*origin + translation, buffers));
+                layer.meshes.push((translation, buffers));
             }
             Primitive::Clip {
                 bounds,
@@ -249,15 +249,21 @@ impl Renderer {
                     layers.push(new_layer);
                 }
             }
-
-            Primitive::Cached { origin, cache } => {
+            Primitive::Translate {
+                translation: new_translation,
+                content,
+            } => {
                 self.draw_primitive(
-                    translation + Vector::new(origin.x, origin.y),
-                    &cache,
+                    translation + *new_translation,
+                    &content,
                     layers,
                 );
             }
 
+            Primitive::Cached { cache } => {
+                self.draw_primitive(translation, &cache, layers);
+            }
+
             #[cfg(feature = "image")]
             Primitive::Image { handle, bounds } => {
                 let layer = layers.last_mut().unwrap();
diff --git a/wgpu/src/renderer/widget/pane_grid.rs b/wgpu/src/renderer/widget/pane_grid.rs
index 2d201fec..11ba6347 100644
--- a/wgpu/src/renderer/widget/pane_grid.rs
+++ b/wgpu/src/renderer/widget/pane_grid.rs
@@ -59,12 +59,12 @@ impl pane_grid::Renderer for Renderer {
                     height: bounds.height + 0.5,
                 },
                 offset: Vector::new(0, 0),
-                content: Box::new(Primitive::Cached {
-                    origin: Point::new(
+                content: Box::new(Primitive::Translate {
+                    translation: Vector::new(
                         cursor_position.x - bounds.x - bounds.width / 2.0,
                         cursor_position.y - bounds.y - bounds.height / 2.0,
                     ),
-                    cache: std::sync::Arc::new(pane),
+                    content: Box::new(pane),
                 }),
             };
 
diff --git a/wgpu/src/triangle.rs b/wgpu/src/triangle.rs
index 99365a4b..b58cc03c 100644
--- a/wgpu/src/triangle.rs
+++ b/wgpu/src/triangle.rs
@@ -1,6 +1,6 @@
 //! Draw meshes of triangles.
 use crate::{settings, Transformation};
-use iced_native::{Point, Rectangle};
+use iced_native::{Rectangle, Vector};
 use std::mem;
 use zerocopy::AsBytes;
 
@@ -201,7 +201,7 @@ impl Pipeline {
         target_width: u32,
         target_height: u32,
         transformation: Transformation,
-        meshes: &[(Point, &Mesh2D)],
+        meshes: &[(Vector, &Mesh2D)],
         bounds: Rectangle<u32>,
     ) {
         // This looks a bit crazy, but we are just counting how many vertices
diff --git a/wgpu/src/widget/canvas.rs b/wgpu/src/widget/canvas.rs
index 2b485e18..744d901e 100644
--- a/wgpu/src/widget/canvas.rs
+++ b/wgpu/src/widget/canvas.rs
@@ -10,7 +10,7 @@ use crate::{Defaults, Primitive, Renderer};
 
 use iced_native::{
     input::mouse, layout, Clipboard, Element, Hasher, Layout, Length,
-    MouseCursor, Point, Size, Widget,
+    MouseCursor, Point, Size, Vector, Widget,
 };
 use std::hash::Hash;
 
@@ -190,20 +190,20 @@ impl<Message, S: State> Widget<Message, Renderer> for Canvas<S> {
         _cursor_position: Point,
     ) -> (Primitive, MouseCursor) {
         let bounds = layout.bounds();
-        let origin = Point::new(bounds.x, bounds.y);
+        let translation = Vector::new(bounds.x, bounds.y);
         let size = Size::new(bounds.width, bounds.height);
 
         (
-            Primitive::Group {
-                primitives: self
-                    .state
-                    .draw(size)
-                    .into_iter()
-                    .map(|geometry| Primitive::Cached {
-                        origin,
-                        cache: geometry.into_primitive(),
-                    })
-                    .collect(),
+            Primitive::Translate {
+                translation,
+                content: Box::new(Primitive::Group {
+                    primitives: self
+                        .state
+                        .draw(size)
+                        .into_iter()
+                        .map(Geometry::into_primitive)
+                        .collect(),
+                }),
             },
             MouseCursor::Idle,
         )
diff --git a/wgpu/src/widget/canvas/cache.rs b/wgpu/src/widget/canvas/cache.rs
index 310bc1d3..12cc6442 100644
--- a/wgpu/src/widget/canvas/cache.rs
+++ b/wgpu/src/widget/canvas/cache.rs
@@ -57,21 +57,27 @@ impl Cache {
         if let State::Filled { bounds, primitive } = self.state.borrow().deref()
         {
             if *bounds == new_bounds {
-                return Geometry::from_primitive(primitive.clone());
+                return Geometry::from_primitive(Primitive::Cached {
+                    cache: primitive.clone(),
+                });
             }
         }
 
         let mut frame = Frame::new(new_bounds);
         input.draw(&mut frame);
 
-        let primitive = Arc::new(frame.into_primitive());
+        let primitive = {
+            let geometry = frame.into_geometry();
+
+            Arc::new(geometry.into_primitive())
+        };
 
         *self.state.borrow_mut() = State::Filled {
             bounds: new_bounds,
             primitive: primitive.clone(),
         };
 
-        Geometry::from_primitive(primitive)
+        Geometry::from_primitive(Primitive::Cached { cache: primitive })
     }
 
     pub fn with<'a, T>(&'a self, input: T) -> impl crate::canvas::State + 'a
diff --git a/wgpu/src/widget/canvas/frame.rs b/wgpu/src/widget/canvas/frame.rs
index a951a029..8623ce4d 100644
--- a/wgpu/src/widget/canvas/frame.rs
+++ b/wgpu/src/widget/canvas/frame.rs
@@ -1,7 +1,7 @@
 use iced_native::{Point, Rectangle, Size, Vector};
 
 use crate::{
-    canvas::{Fill, Path, Stroke, Text},
+    canvas::{Fill, Geometry, Path, Stroke, Text},
     triangle, Primitive,
 };
 
@@ -260,13 +260,13 @@ impl Frame {
         self.transforms.current.is_identity = false;
     }
 
-    /// Produces the primitive representing everything drawn on the [`Frame`].
+    /// Produces the [`Geometry`] representing everything drawn on the [`Frame`].
     ///
     /// [`Frame`]: struct.Frame.html
-    pub fn into_primitive(mut self) -> Primitive {
+    /// [`Geometry`]: struct.Geometry.html
+    pub fn into_geometry(mut self) -> Geometry {
         if !self.buffers.indices.is_empty() {
             self.primitives.push(Primitive::Mesh2D {
-                origin: Point::ORIGIN,
                 buffers: triangle::Mesh2D {
                     vertices: self.buffers.vertices,
                     indices: self.buffers.indices,
@@ -274,9 +274,9 @@ impl Frame {
             });
         }
 
-        Primitive::Group {
+        Geometry::from_primitive(Primitive::Group {
             primitives: self.primitives,
-        }
+        })
     }
 }
 
diff --git a/wgpu/src/widget/canvas/geometry.rs b/wgpu/src/widget/canvas/geometry.rs
index db7b4054..12ef828f 100644
--- a/wgpu/src/widget/canvas/geometry.rs
+++ b/wgpu/src/widget/canvas/geometry.rs
@@ -1,15 +1,20 @@
 use crate::Primitive;
-use std::sync::Arc;
 
-#[derive(Debug)]
-pub struct Geometry(Arc<Primitive>);
+#[derive(Debug, Clone)]
+pub struct Geometry(Primitive);
 
 impl Geometry {
-    pub(crate) fn from_primitive(primitive: Arc<Primitive>) -> Self {
+    pub(crate) fn from_primitive(primitive: Primitive) -> Self {
         Self(primitive)
     }
 
-    pub(crate) fn into_primitive(self) -> Arc<Primitive> {
+    pub fn into_primitive(self) -> Primitive {
         self.0
     }
 }
+
+impl From<Geometry> for Primitive {
+    fn from(geometry: Geometry) -> Primitive {
+        geometry.0
+    }
+}