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+//! Write a graphics backend.
+use iced_native::image;
+use iced_native::svg;
+use iced_native::{Font, Size};
+
+/// The graphics backend of a [`Renderer`].
+///
+/// [`Renderer`]: ../struct.Renderer.html
+pub trait Backend {
+ /// Trims the measurements cache.
+ ///
+ /// This method is currently necessary to properly trim the text cache in
+ /// `iced_wgpu` and `iced_glow` because of limitations in the text rendering
+ /// pipeline. It will be removed in the future.
+ fn trim_measurements(&mut self) {}
+}
+
+/// A graphics backend that supports text rendering.
+pub trait Text {
+ /// The icon font of the backend.
+ const ICON_FONT: Font;
+
+ /// The `char` representing a ✔ icon in the [`ICON_FONT`].
+ ///
+ /// [`ICON_FONT`]: #associatedconst.ICON_FONt
+ const CHECKMARK_ICON: char;
+
+ /// Measures the text contents with the given size and font,
+ /// returning the size of a laid out paragraph that fits in the provided
+ /// bounds.
+ fn measure(
+ &self,
+ contents: &str,
+ size: f32,
+ font: Font,
+ bounds: Size,
+ ) -> (f32, f32);
+}
+
+/// A graphics backend that supports image rendering.
+pub trait Image {
+ /// Returns the dimensions of the provided image.
+ fn dimensions(&self, handle: &image::Handle) -> (u32, u32);
+}
+
+/// A graphics backend that supports SVG rendering.
+pub trait Svg {
+ /// Returns the viewport dimensions of the provided SVG.
+ fn viewport_dimensions(&self, handle: &svg::Handle) -> (u32, u32);
+}