1 files changed, 158 insertions, 0 deletions
diff --git a/tiny_skia/src/window/compositor.rs b/tiny_skia/src/window/compositor.rs
new file mode 100644
index 00000000..9999a188
--- /dev/null
+++ b/tiny_skia/src/window/compositor.rs
@@ -0,0 +1,158 @@
+use crate::core::{Color, Rectangle};
+use crate::graphics::compositor::{self, Information, SurfaceError};
+use crate::graphics::damage;
+use crate::graphics::{Error, Primitive, Viewport};
+use crate::{Backend, Renderer, Settings};
+
+use raw_window_handle::{HasRawDisplayHandle, HasRawWindowHandle};
+use std::marker::PhantomData;
+
+pub struct Compositor<Theme> {
+    _theme: PhantomData<Theme>,
+}
+
+pub struct Surface {
+    window: softbuffer::GraphicsContext,
+    buffer: Vec<u32>,
+    clip_mask: tiny_skia::Mask,
+    primitives: Option<Vec<Primitive>>,
+    background_color: Color,
+}
+
+impl<Theme> crate::graphics::Compositor for Compositor<Theme> {
+    type Settings = Settings;
+    type Renderer = Renderer<Theme>;
+    type Surface = Surface;
+
+    fn new<W: HasRawWindowHandle + HasRawDisplayHandle>(
+        settings: Self::Settings,
+        _compatible_window: Option<&W>,
+    ) -> Result<(Self, Self::Renderer), Error> {
+        let (compositor, backend) = new(settings);
+
+        Ok((compositor, Renderer::new(backend)))
+    }
+
+    fn create_surface<W: HasRawWindowHandle + HasRawDisplayHandle>(
+        &mut self,
+        window: &W,
+        width: u32,
+        height: u32,
+    ) -> Surface {
+        let window =
+            unsafe { softbuffer::GraphicsContext::new(window, window) }
+                .expect("Create softbuffer for window");
+
+        Surface {
+            window,
+            buffer: vec![0; width as usize * height as usize],
+            clip_mask: tiny_skia::Mask::new(width, height)
+                .expect("Create clip mask"),
+            primitives: None,
+            background_color: Color::BLACK,
+        }
+    }
+
+    fn configure_surface(
+        &mut self,
+        surface: &mut Surface,
+        width: u32,
+        height: u32,
+    ) {
+        surface.buffer.resize((width * height) as usize, 0);
+        surface.clip_mask =
+            tiny_skia::Mask::new(width, height).expect("Create clip mask");
+        surface.primitives = None;
+    }
+
+    fn fetch_information(&self) -> Information {
+        Information {
+            adapter: String::from("CPU"),
+            backend: String::from("tiny-skia"),
+        }
+    }
+
+    fn present<T: AsRef<str>>(
+        &mut self,
+        renderer: &mut Self::Renderer,
+        surface: &mut Self::Surface,
+        viewport: &Viewport,
+        background_color: Color,
+        overlay: &[T],
+    ) -> Result<(), SurfaceError> {
+        renderer.with_primitives(|backend, primitives| {
+            present(
+                backend,
+                surface,
+                primitives,
+                viewport,
+                background_color,
+                overlay,
+            )
+        })
+    }
+}
+
+pub fn new<Theme>(settings: Settings) -> (Compositor<Theme>, Backend) {
+    (
+        Compositor {
+            _theme: PhantomData,
+        },
+        Backend::new(settings),
+    )
+}
+
+pub fn present<T: AsRef<str>>(
+    backend: &mut Backend,
+    surface: &mut Surface,
+    primitives: &[Primitive],
+    viewport: &Viewport,
+    background_color: Color,
+    overlay: &[T],
+) -> Result<(), compositor::SurfaceError> {
+    let physical_size = viewport.physical_size();
+    let scale_factor = viewport.scale_factor() as f32;
+
+    let mut pixels = tiny_skia::PixmapMut::from_bytes(
+        bytemuck::cast_slice_mut(&mut surface.buffer),
+        physical_size.width,
+        physical_size.height,
+    )
+    .expect("Create pixel map");
+
+    let damage = surface
+        .primitives
+        .as_deref()
+        .and_then(|last_primitives| {
+            (surface.background_color == background_color)
+                .then(|| damage::list(last_primitives, primitives))
+        })
+        .unwrap_or_else(|| vec![Rectangle::with_size(viewport.logical_size())]);
+
+    if damage.is_empty() {
+        return Ok(());
+    }
+
+    surface.primitives = Some(primitives.to_vec());
+    surface.background_color = background_color;
+
+    let damage = damage::group(damage, scale_factor, physical_size);
+
+    backend.draw(
+        &mut pixels,
+        &mut surface.clip_mask,
+        primitives,
+        viewport,
+        &damage,
+        background_color,
+        overlay,
+    );
+
+    surface.window.set_buffer(
+        &surface.buffer,
+        physical_size.width as u16,
+        physical_size.height as u16,
+    );
+
+    Ok(())
+}