Merge pull request #1748 from iced-rs/feature/software-renderer

Software renderer, runtime renderer fallback, and core consolidation

1 files changed, 82 insertions, 0 deletions

diff --git a/core/src/renderer/null.rs b/core/src/renderer/null.rs
new file mode 100644
index 00000000..d93338ae
--- /dev/null
+++ b/core/src/renderer/null.rs
@@ -0,0 +1,82 @@
+use crate::renderer::{self, Renderer};
+use crate::text::{self, Text};
+use crate::{Background, Font, Point, Rectangle, Size, Vector};
+
+use std::borrow::Cow;
+
+/// A renderer that does nothing.
+///
+/// It can be useful if you are writing tests!
+#[derive(Debug, Clone, Copy, Default)]
+pub struct Null;
+
+impl Null {
+    /// Creates a new [`Null`] renderer.
+    pub fn new() -> Null {
+        Null
+    }
+}
+
+impl Renderer for Null {
+    type Theme = ();
+
+    fn with_layer(&mut self, _bounds: Rectangle, _f: impl FnOnce(&mut Self)) {}
+
+    fn with_translation(
+        &mut self,
+        _translation: Vector,
+        _f: impl FnOnce(&mut Self),
+    ) {
+    }
+
+    fn clear(&mut self) {}
+
+    fn fill_quad(
+        &mut self,
+        _quad: renderer::Quad,
+        _background: impl Into<Background>,
+    ) {
+    }
+}
+
+impl text::Renderer for Null {
+    type Font = Font;
+
+    const ICON_FONT: Font = Font::SansSerif;
+    const CHECKMARK_ICON: char = '0';
+    const ARROW_DOWN_ICON: char = '0';
+
+    fn default_font(&self) -> Self::Font {
+        Font::SansSerif
+    }
+
+    fn default_size(&self) -> f32 {
+        16.0
+    }
+
+    fn load_font(&mut self, _font: Cow<'static, [u8]>) {}
+
+    fn measure(
+        &self,
+        _content: &str,
+        _size: f32,
+        _font: Font,
+        _bounds: Size,
+    ) -> (f32, f32) {
+        (0.0, 20.0)
+    }
+
+    fn hit_test(
+        &self,
+        _contents: &str,
+        _size: f32,
+        _font: Self::Font,
+        _bounds: Size,
+        _point: Point,
+        _nearest_only: bool,
+    ) -> Option<text::Hit> {
+        None
+    }
+
+    fn fill_text(&mut self, _text: Text<'_, Self::Font>) {}
+}