add gui in os

os/src/gui/graphic.rs

@@ -0,0 +1,56 @@
+use alloc::sync::Arc;
+use embedded_graphics::{
+    draw_target::DrawTarget,
+    pixelcolor::Rgb888,
+    prelude::{OriginDimensions, Point, RgbColor, Size},
+};
+
+use crate::drivers::{GPUDevice, GPU_DEVICE};
+
+#[derive(Clone)]
+pub struct Graphics {
+    pub size: Size,
+    pub point: Point,
+    pub drv: Arc<dyn GPUDevice>,
+}
+
+impl Graphics {
+    pub fn new(size: Size, point: Point) -> Self {
+        Self {
+            size,
+            point,
+            drv: GPU_DEVICE.clone()
+        }
+    }
+}
+
+impl OriginDimensions for Graphics {
+    fn size(&self) -> Size {
+        self.size
+    }
+}
+
+impl DrawTarget for Graphics {
+    type Color = Rgb888;
+
+    type Error = core::convert::Infallible;
+
+    fn draw_iter<I>(&mut self, pixels: I) -> Result<(), Self::Error>
+    where
+        I: IntoIterator<Item = embedded_graphics::Pixel<Self::Color>>,
+    {
+        let fb = self.drv.getfreambuffer();
+
+        pixels.into_iter().for_each(|px| {
+            let idx = ((self.point.y + px.0.y) * 1024 + self.point.x + px.0.x) as usize * 4;
+            if idx + 2 >= fb.len() {
+                return;
+            }
+            fb[idx] = px.1.b();
+            fb[idx + 1] = px.1.g();
+            fb[idx + 2] = px.1.r();
+        });
+        self.drv.flush();
+        Ok(())
+    }
+}