feat: wayland

src/wayland/core/shm_buffer_backing.rs

@@ -0,0 +1,102 @@
+use super::shm_pool::ShmPool;
+use bevy::{
+	asset::{Assets, Handle, RenderAssetUsages},
+	image::Image,
+	render::render_resource::{Extent3d, TextureDimension, TextureFormat},
+};
+use mint::Vector2;
+use std::sync::{Arc, OnceLock};
+use waynest::server::protocol::core::wayland::wl_shm::Format;
+
+/// Parameters for a shared memory buffer
+#[derive(Debug)]
+pub struct ShmBufferBacking {
+	pool: Arc<ShmPool>,
+	offset: usize,
+	stride: usize,
+	size: Vector2<usize>,
+	format: Format,
+	image: OnceLock<Handle<Image>>,
+}
+
+impl ShmBufferBacking {
+	pub fn new(
+		pool: Arc<ShmPool>,
+		offset: usize,
+		stride: usize,
+		size: Vector2<usize>,
+		format: Format,
+	) -> Self {
+		Self {
+			pool,
+			offset,
+			stride,
+			size,
+			format,
+			image: OnceLock::new(),
+		}
+	}
+
+	pub fn update_tex(&self, images: &mut Assets<Image>) -> Option<Handle<Image>> {
+		let image = self.image.get_or_init(|| {
+			let image = Image::new_fill(
+				Extent3d {
+					width: self.size.x as u32,
+					height: self.size.y as u32,
+					depth_or_array_layers: 1,
+				},
+				TextureDimension::D2,
+				&[255, 0, 255, 255],
+				TextureFormat::Rgba8Unorm,
+				RenderAssetUsages::all(),
+			);
+			images.add(image)
+		});
+
+		let src_data_lock = self.pool.data_lock();
+		let mut src_cursor = self.offset;
+
+		// Calculate maximum cursor position needed - stride is already in bytes
+		let max_cursor = self.offset + (self.size.y * self.stride);
+
+		// Check if we have enough data
+		if max_cursor > src_data_lock.len() {
+			return None;
+		}
+
+		let dst_data = images.get_mut(image).unwrap().data.get_or_insert_with(|| {
+			let length = self.size.x as usize * self.size.y as usize * 4;
+			vec![255; length]
+		});
+		let mut dst_cursor = 0;
+
+		for _y in 0..self.size.y {
+			for _x in 0..self.size.x {
+				match self.format {
+					Format::Xrgb8888 => {
+						dst_data[dst_cursor] = src_data_lock[src_cursor + 2]; // Red is byte 2
+						dst_data[dst_cursor + 1] = src_data_lock[src_cursor + 1]; // Green is byte 1
+						dst_data[dst_cursor + 2] = src_data_lock[src_cursor]; // Blue is byte 0
+						dst_data[dst_cursor + 3] = 255; // X means ignore alpha, treat as fully opaque
+					}
+					Format::Argb8888 => {
+						dst_data[dst_cursor] = src_data_lock[src_cursor + 2]; // Red is byte 2
+						dst_data[dst_cursor + 1] = src_data_lock[src_cursor + 1]; // Green is byte 1
+						dst_data[dst_cursor + 2] = src_data_lock[src_cursor]; // Blue is byte 0
+						dst_data[dst_cursor + 3] = src_data_lock[src_cursor + 3]; // Alpha is byte 3
+					}
+					_ => panic!("Unsupported format {:?}", self.format),
+				}
+				src_cursor += 4;
+				dst_cursor += 4;
+			}
+			src_cursor += self.stride - (self.size.x * 4);
+		}
+
+		Some(image.clone())
+	}
+
+	pub fn size(&self) -> Vector2<usize> {
+		self.size
+	}
+}