4 files changed, 301 insertions, 0 deletions
diff --git a/src/render_helpers/mod.rs b/src/render_helpers/mod.rs
new file mode 100644
index 00000000..fc7a9c85
--- /dev/null
+++ b/src/render_helpers/mod.rs
@@ -0,0 +1,3 @@
+pub mod primary_gpu_texture;
+pub mod render_elements;
+pub mod renderer;
diff --git a/src/render_helpers/primary_gpu_texture.rs b/src/render_helpers/primary_gpu_texture.rs
new file mode 100644
index 00000000..a3835c49
--- /dev/null
+++ b/src/render_helpers/primary_gpu_texture.rs
@@ -0,0 +1,99 @@
+use smithay::backend::renderer::element::texture::TextureRenderElement;
+use smithay::backend::renderer::element::{Element, Id, Kind, RenderElement, UnderlyingStorage};
+use smithay::backend::renderer::gles::{GlesError, GlesFrame, GlesRenderer, GlesTexture};
+use smithay::backend::renderer::utils::CommitCounter;
+use smithay::utils::{Buffer, Physical, Rectangle, Scale, Transform};
+
+use super::renderer::AsGlesFrame;
+use crate::backend::tty::{TtyFrame, TtyRenderer, TtyRendererError};
+
+/// Wrapper for a texture from the primary GPU for rendering with the primary GPU.
+#[derive(Debug)]
+pub struct PrimaryGpuTextureRenderElement(pub TextureRenderElement<GlesTexture>);
+
+impl Element for PrimaryGpuTextureRenderElement {
+    fn id(&self) -> &Id {
+        self.0.id()
+    }
+
+    fn current_commit(&self) -> CommitCounter {
+        self.0.current_commit()
+    }
+
+    fn geometry(&self, scale: Scale<f64>) -> Rectangle<i32, Physical> {
+        self.0.geometry(scale)
+    }
+
+    fn transform(&self) -> Transform {
+        self.0.transform()
+    }
+
+    fn src(&self) -> Rectangle<f64, Buffer> {
+        self.0.src()
+    }
+
+    fn damage_since(
+        &self,
+        scale: Scale<f64>,
+        commit: Option<CommitCounter>,
+    ) -> Vec<Rectangle<i32, Physical>> {
+        self.0.damage_since(scale, commit)
+    }
+
+    fn opaque_regions(&self, scale: Scale<f64>) -> Vec<Rectangle<i32, Physical>> {
+        self.0.opaque_regions(scale)
+    }
+
+    fn alpha(&self) -> f32 {
+        self.0.alpha()
+    }
+
+    fn kind(&self) -> Kind {
+        self.0.kind()
+    }
+}
+
+impl RenderElement<GlesRenderer> for PrimaryGpuTextureRenderElement {
+    fn draw(
+        &self,
+        frame: &mut GlesFrame<'_>,
+        src: Rectangle<f64, Buffer>,
+        dst: Rectangle<i32, Physical>,
+        damage: &[Rectangle<i32, Physical>],
+    ) -> Result<(), GlesError> {
+        let gles_frame = frame.as_gles_frame();
+        RenderElement::<GlesRenderer>::draw(&self.0, gles_frame, src, dst, damage)?;
+        Ok(())
+    }
+
+    fn underlying_storage(&self, _renderer: &mut GlesRenderer) -> Option<UnderlyingStorage> {
+        // If scanout for things other than Wayland buffers is implemented, this will need to take
+        // the target GPU into account.
+        None
+    }
+}
+
+impl<'render, 'alloc> RenderElement<TtyRenderer<'render, 'alloc>>
+    for PrimaryGpuTextureRenderElement
+{
+    fn draw(
+        &self,
+        frame: &mut TtyFrame<'_, '_, '_>,
+        src: Rectangle<f64, Buffer>,
+        dst: Rectangle<i32, Physical>,
+        damage: &[Rectangle<i32, Physical>],
+    ) -> Result<(), TtyRendererError<'render, 'alloc>> {
+        let gles_frame = frame.as_gles_frame();
+        RenderElement::<GlesRenderer>::draw(&self.0, gles_frame, src, dst, damage)?;
+        Ok(())
+    }
+
+    fn underlying_storage(
+        &self,
+        _renderer: &mut TtyRenderer<'render, 'alloc>,
+    ) -> Option<UnderlyingStorage> {
+        // If scanout for things other than Wayland buffers is implemented, this will need to take
+        // the target GPU into account.
+        None
+    }
+}
diff --git a/src/render_helpers/render_elements.rs b/src/render_helpers/render_elements.rs
new file mode 100644
index 00000000..d6423bff
--- /dev/null
+++ b/src/render_helpers/render_elements.rs
@@ -0,0 +1,126 @@
+// We need to implement RenderElement manually due to AsGlesFrame requirement.
+// This macro does it for us.
+#[macro_export]
+macro_rules! niri_render_elements {
+    ($name:ident => { $($variant:ident = $type:ty),+ $(,)? }) => {
+        #[derive(Debug)]
+        pub enum $name<R: $crate::render_helpers::renderer::NiriRenderer> {
+            $($variant($type)),+
+        }
+
+        impl<R: $crate::render_helpers::renderer::NiriRenderer> smithay::backend::renderer::element::Element for $name<R> {
+            fn id(&self) -> &smithay::backend::renderer::element::Id {
+                match self {
+                    $($name::$variant(elem) => elem.id()),+
+                }
+            }
+
+            fn current_commit(&self) -> smithay::backend::renderer::utils::CommitCounter {
+                match self {
+                    $($name::$variant(elem) => elem.current_commit()),+
+                }
+            }
+
+            fn geometry(&self, scale: smithay::utils::Scale<f64>) -> Rectangle<i32, smithay::utils::Physical> {
+                match self {
+                    $($name::$variant(elem) => elem.geometry(scale)),+
+                }
+            }
+
+            fn transform(&self) -> smithay::utils::Transform {
+                match self {
+                    $($name::$variant(elem) => elem.transform()),+
+                }
+            }
+
+            fn src(&self) -> smithay::utils::Rectangle<f64, smithay::utils::Buffer> {
+                match self {
+                    $($name::$variant(elem) => elem.src()),+
+                }
+            }
+
+            fn damage_since(
+                &self,
+                scale: smithay::utils::Scale<f64>,
+                commit: Option<smithay::backend::renderer::utils::CommitCounter>,
+            ) -> Vec<smithay::utils::Rectangle<i32, smithay::utils::Physical>> {
+                match self {
+                    $($name::$variant(elem) => elem.damage_since(scale, commit)),+
+                }
+            }
+
+            fn opaque_regions(&self, scale: smithay::utils::Scale<f64>) -> Vec<smithay::utils::Rectangle<i32, smithay::utils::Physical>> {
+                match self {
+                    $($name::$variant(elem) => elem.opaque_regions(scale)),+
+                }
+            }
+
+            fn alpha(&self) -> f32 {
+                match self {
+                    $($name::$variant(elem) => elem.alpha()),+
+                }
+            }
+
+            fn kind(&self) -> smithay::backend::renderer::element::Kind {
+                match self {
+                    $($name::$variant(elem) => elem.kind()),+
+                }
+            }
+        }
+
+        impl smithay::backend::renderer::element::RenderElement<smithay::backend::renderer::gles::GlesRenderer> for $name<smithay::backend::renderer::gles::GlesRenderer> {
+            fn draw(
+                &self,
+                frame: &mut smithay::backend::renderer::gles::GlesFrame<'_>,
+                src: smithay::utils::Rectangle<f64, smithay::utils::Buffer>,
+                dst: smithay::utils::Rectangle<i32, smithay::utils::Physical>,
+                damage: &[smithay::utils::Rectangle<i32, smithay::utils::Physical>],
+            ) -> Result<(), smithay::backend::renderer::gles::GlesError> {
+                match self {
+                    $($name::$variant(elem) => {
+                        smithay::backend::renderer::element::RenderElement::<smithay::backend::renderer::gles::GlesRenderer>::draw(elem, frame, src, dst, damage)
+                    })+
+                }
+            }
+
+            fn underlying_storage(&self, renderer: &mut smithay::backend::renderer::gles::GlesRenderer) -> Option<smithay::backend::renderer::element::UnderlyingStorage> {
+                match self {
+                    $($name::$variant(elem) => elem.underlying_storage(renderer)),+
+                }
+            }
+        }
+
+        impl<'render, 'alloc> smithay::backend::renderer::element::RenderElement<$crate::backend::tty::TtyRenderer<'render, 'alloc>>
+            for $name<$crate::backend::tty::TtyRenderer<'render, 'alloc>>
+        {
+            fn draw(
+                &self,
+                frame: &mut $crate::backend::tty::TtyFrame<'render, 'alloc, '_>,
+                src: smithay::utils::Rectangle<f64, smithay::utils::Buffer>,
+                dst: smithay::utils::Rectangle<i32, smithay::utils::Physical>,
+                damage: &[smithay::utils::Rectangle<i32, smithay::utils::Physical>],
+            ) -> Result<(), $crate::backend::tty::TtyRendererError<'render, 'alloc>> {
+                match self {
+                    $($name::$variant(elem) => {
+                        smithay::backend::renderer::element::RenderElement::<$crate::backend::tty::TtyRenderer<'render, 'alloc>>::draw(elem, frame, src, dst, damage)
+                    })+
+                }
+            }
+
+            fn underlying_storage(
+                &self,
+                renderer: &mut $crate::backend::tty::TtyRenderer<'render, 'alloc>,
+            ) -> Option<smithay::backend::renderer::element::UnderlyingStorage> {
+                match self {
+                    $($name::$variant(elem) => elem.underlying_storage(renderer)),+
+                }
+            }
+        }
+
+        $(impl<R: $crate::render_helpers::renderer::NiriRenderer> From<$type> for $name<R> {
+            fn from(x: $type) -> Self {
+                Self::$variant(x)
+            }
+        })+
+    };
+}
diff --git a/src/render_helpers/renderer.rs b/src/render_helpers/renderer.rs
new file mode 100644
index 00000000..7f85b66d
--- /dev/null
+++ b/src/render_helpers/renderer.rs
@@ -0,0 +1,73 @@
+use smithay::backend::allocator::dmabuf::Dmabuf;
+use smithay::backend::renderer::gles::{GlesFrame, GlesRenderer, GlesTexture};
+use smithay::backend::renderer::{
+    Bind, ExportMem, ImportAll, ImportMem, Offscreen, Renderer, Texture,
+};
+
+use crate::backend::tty::{TtyFrame, TtyRenderer};
+
+/// Trait with our main renderer requirements to save on the typing.
+pub trait NiriRenderer:
+    ImportAll
+    + ImportMem
+    + ExportMem
+    + Bind<Dmabuf>
+    + Offscreen<GlesTexture>
+    + Renderer<TextureId = Self::NiriTextureId, Error = Self::NiriError>
+    + AsGlesRenderer
+{
+    // Associated types to work around the instability of associated type bounds.
+    type NiriTextureId: Texture + Clone + 'static;
+    type NiriError: std::error::Error
+        + Send
+        + Sync
+        + From<<GlesRenderer as Renderer>::Error>
+        + 'static;
+}
+
+impl<R> NiriRenderer for R
+where
+    R: ImportAll + ImportMem + ExportMem + Bind<Dmabuf> + Offscreen<GlesTexture> + AsGlesRenderer,
+    R::TextureId: Texture + Clone + 'static,
+    R::Error: std::error::Error + Send + Sync + From<<GlesRenderer as Renderer>::Error> + 'static,
+{
+    type NiriTextureId = R::TextureId;
+    type NiriError = R::Error;
+}
+
+/// Trait for getting the underlying `GlesRenderer`.
+pub trait AsGlesRenderer {
+    fn as_gles_renderer(&mut self) -> &mut GlesRenderer;
+}
+
+impl AsGlesRenderer for GlesRenderer {
+    fn as_gles_renderer(&mut self) -> &mut GlesRenderer {
+        self
+    }
+}
+
+impl<'render, 'alloc> AsGlesRenderer for TtyRenderer<'render, 'alloc> {
+    fn as_gles_renderer(&mut self) -> &mut GlesRenderer {
+        self.as_mut()
+    }
+}
+
+/// Trait for getting the underlying `GlesFrame`.
+pub trait AsGlesFrame<'frame>
+where
+    Self: 'frame,
+{
+    fn as_gles_frame(&mut self) -> &mut GlesFrame<'frame>;
+}
+
+impl<'frame> AsGlesFrame<'frame> for GlesFrame<'frame> {
+    fn as_gles_frame(&mut self) -> &mut GlesFrame<'frame> {
+        self
+    }
+}
+
+impl<'render, 'alloc, 'frame> AsGlesFrame<'frame> for TtyFrame<'render, 'alloc, 'frame> {
+    fn as_gles_frame(&mut self) -> &mut GlesFrame<'frame> {
+        self.as_mut()
+    }
+}