From 45455be45000c0d41d18eced1b62eab049c5e9c0 Mon Sep 17 00:00:00 2001
From: Héctor Ramón Jiménez <hector0193@gmail.com>
Date: Sun, 13 Feb 2022 16:51:31 +0700
Subject: Implement `Image` in `iced_pure`

---
 native/src/widget/image.rs | 73 ++++++++++++++++++++++++++++++---------------
 pure/src/widget.rs         |  7 +++++
 pure/src/widget/image.rs   | 74 ++++++++++++++++++++++++++++++++++++++++++++++
 src/pure.rs                |  5 +++-
 4 files changed, 134 insertions(+), 25 deletions(-)
 create mode 100644 pure/src/widget/image.rs

diff --git a/native/src/widget/image.rs b/native/src/widget/image.rs
index b8fb662e..5e03bf99 100644
--- a/native/src/widget/image.rs
+++ b/native/src/widget/image.rs
@@ -51,6 +51,53 @@ impl<Handle> Image<Handle> {
     }
 }
 
+/// Computes the layout of an [`Image`].
+pub fn layout<Renderer, Handle>(
+    renderer: &Renderer,
+    limits: &layout::Limits,
+    handle: &Handle,
+    width: Length,
+    height: Length,
+) -> layout::Node
+where
+    Renderer: image::Renderer<Handle = Handle>,
+{
+    let (original_width, original_height) = renderer.dimensions(handle);
+
+    let mut size = limits
+        .width(width)
+        .height(height)
+        .resolve(Size::new(original_width as f32, original_height as f32));
+
+    let aspect_ratio = original_width as f32 / original_height as f32;
+    let viewport_aspect_ratio = size.width / size.height;
+
+    if viewport_aspect_ratio > aspect_ratio {
+        size.width =
+            original_width as f32 * size.height / original_height as f32;
+    } else {
+        size.height =
+            original_height as f32 * size.width / original_width as f32;
+    }
+
+    layout::Node::new(size)
+}
+
+/// Hashes the layout attributes of an [`Image`].
+pub fn hash_layout<Handle: Hash>(
+    state: &mut Hasher,
+    handle: &Handle,
+    width: Length,
+    height: Length,
+) {
+    struct Marker;
+    std::any::TypeId::of::<Marker>().hash(state);
+
+    handle.hash(state);
+    width.hash(state);
+    height.hash(state);
+}
+
 impl<Message, Renderer, Handle> Widget<Message, Renderer> for Image<Handle>
 where
     Renderer: image::Renderer<Handle = Handle>,
@@ -69,24 +116,7 @@ where
         renderer: &Renderer,
         limits: &layout::Limits,
     ) -> layout::Node {
-        let (width, height) = renderer.dimensions(&self.handle);
-
-        let aspect_ratio = width as f32 / height as f32;
-
-        let mut size = limits
-            .width(self.width)
-            .height(self.height)
-            .resolve(Size::new(width as f32, height as f32));
-
-        let viewport_aspect_ratio = size.width / size.height;
-
-        if viewport_aspect_ratio > aspect_ratio {
-            size.width = width as f32 * size.height / height as f32;
-        } else {
-            size.height = height as f32 * size.width / width as f32;
-        }
-
-        layout::Node::new(size)
+        layout(renderer, limits, &self.handle, self.width, self.height)
     }
 
     fn draw(
@@ -101,12 +131,7 @@ where
     }
 
     fn hash_layout(&self, state: &mut Hasher) {
-        struct Marker;
-        std::any::TypeId::of::<Marker>().hash(state);
-
-        self.handle.hash(state);
-        self.width.hash(state);
-        self.height.hash(state);
+        hash_layout(state, &self.handle, self.width, self.height)
     }
 }
 
diff --git a/pure/src/widget.rs b/pure/src/widget.rs
index 302a057a..93298c61 100644
--- a/pure/src/widget.rs
+++ b/pure/src/widget.rs
@@ -1,3 +1,5 @@
+pub mod image;
+
 mod button;
 mod checkbox;
 mod column;
@@ -14,6 +16,7 @@ pub use checkbox::Checkbox;
 pub use column::Column;
 pub use container::Container;
 pub use element::Element;
+pub use image::Image;
 pub use row::Row;
 pub use scrollable::Scrollable;
 pub use text::Text;
@@ -145,3 +148,7 @@ where
 {
     TextInput::new(placeholder, value, on_change)
 }
+
+pub fn image<Handle>(handle: Handle) -> Image<Handle> {
+    Image::new(handle)
+}
diff --git a/pure/src/widget/image.rs b/pure/src/widget/image.rs
new file mode 100644
index 00000000..b33dad2b
--- /dev/null
+++ b/pure/src/widget/image.rs
@@ -0,0 +1,74 @@
+use crate::widget::{Tree, Widget};
+
+use iced_native::layout::{self, Layout};
+use iced_native::renderer;
+use iced_native::widget::image;
+use iced_native::{Hasher, Length, Point, Rectangle};
+
+use std::any::{self, Any};
+use std::hash::Hash;
+
+pub use image::Image;
+
+impl<Message, Renderer, Handle> Widget<Message, Renderer> for Image<Handle>
+where
+    Handle: Clone + Hash,
+    Renderer: iced_native::image::Renderer<Handle = Handle>,
+{
+    fn tag(&self) -> any::TypeId {
+        any::TypeId::of::<()>()
+    }
+
+    fn state(&self) -> Box<dyn Any> {
+        Box::new(())
+    }
+
+    fn children_state(&self) -> Vec<Tree> {
+        Vec::new()
+    }
+
+    fn diff(&self, _tree: &mut Tree) {}
+
+    fn width(&self) -> Length {
+        <Self as iced_native::Widget<Message, Renderer>>::width(self)
+    }
+
+    fn height(&self) -> Length {
+        <Self as iced_native::Widget<Message, Renderer>>::height(self)
+    }
+
+    fn layout(
+        &self,
+        renderer: &Renderer,
+        limits: &layout::Limits,
+    ) -> layout::Node {
+        <Self as iced_native::Widget<Message, Renderer>>::layout(
+            self, renderer, limits,
+        )
+    }
+
+    fn draw(
+        &self,
+        _tree: &Tree,
+        renderer: &mut Renderer,
+        style: &renderer::Style,
+        layout: Layout<'_>,
+        cursor_position: Point,
+        viewport: &Rectangle,
+    ) {
+        <Self as iced_native::Widget<Message, Renderer>>::draw(
+            self,
+            renderer,
+            style,
+            layout,
+            cursor_position,
+            viewport,
+        )
+    }
+
+    fn hash_layout(&self, state: &mut Hasher) {
+        <Self as iced_native::Widget<Message, Renderer>>::hash_layout(
+            self, state,
+        )
+    }
+}
diff --git a/src/pure.rs b/src/pure.rs
index 29495c07..712bd31f 100644
--- a/src/pure.rs
+++ b/src/pure.rs
@@ -17,7 +17,7 @@
 //! [the original widgets]: crate::widget
 //! [`button::State`]: crate::widget::button::State
 //! [impure `Application`]: crate::Application
-pub use iced_pure::{Element as _, Text as _, *};
+pub use iced_pure::{Element as _, Image as _, Text as _, *};
 
 /// A generic, pure [`Widget`].
 pub type Element<'a, Message> =
@@ -26,6 +26,9 @@ pub type Element<'a, Message> =
 /// A pure text widget.
 pub type Text = iced_pure::Text<crate::Renderer>;
 
+/// A pure image widget.
+pub type Image = iced_pure::Image<crate::widget::image::Handle>;
+
 mod application;
 mod sandbox;
 
-- 
cgit