Add fast rectangle drawing

src/lib.rs

@@ -285,16 +285,16 @@ where
     }
 }
 
-#[cfg(feature = "graphics")]
-use embedded_graphics::drawable;
 #[cfg(feature = "graphics")]
 use embedded_graphics::{
     drawable::Pixel,
-    geometry::Size,
+    geometry::{Point, Size},
     pixelcolor::{
         raw::{RawData, RawU16},
         Rgb565,
     },
+    primitives::Rectangle,
+    style::{PrimitiveStyle, Styled},
     DrawTarget,
 };
 
@@ -314,7 +314,7 @@ where
     fn draw_pixel(&mut self, pixel: Pixel<Rgb565>) -> Result<(), Self::Error> {
         let Pixel(pos, color) = pixel;
 
-        if pos.x < 0 || pos.y < 0 || pos.x > self.width as i32 || pos.y > self.height as i32 {
+        if pos.x < 0 || pos.y < 0 || pos.x >= self.width as i32 || pos.y >= self.height as i32 {
             return Ok(());
         }
 
@@ -326,6 +326,43 @@ where
             &[RawU16::from(color).into_inner()],
         )
     }
+    fn draw_rectangle(
+        &mut self,
+        item: &Styled<Rectangle, PrimitiveStyle<Rgb565>>,
+    ) -> Result<(), Self::Error> {
+        let Point { x: x0, y: y0 } = item.primitive.top_left;
+        let Point { x: x1, y: y1 } = item.primitive.bottom_right;
+        let w = self.width as i32;
+        let h = self.height as i32;
+        if x0 >= w || y0 >= h {
+            return Ok(());
+        }
+        fn clamp(v: i32, max: i32) -> u16 {
+            if v < 0 {
+                0
+            } else if v > max {
+                max as u16
+            } else {
+                v as u16
+            }
+        }
+        let x0 = clamp(x0, w - 1);
+        let y0 = clamp(y0, h - 1);
+        let x1 = clamp(x1, w - 1);
+        let y1 = clamp(y1, h - 1);
+        self.draw_iter(
+            x0,
+            y0,
+            x1,
+            y1,
+            item.into_iter()
+                .filter(|p| {
+                    let Point { x, y } = p.0;
+                    x >= 0 && y >= 0 && x < w && y < h
+                })
+                .map(|p| RawU16::from(p.1).into_inner()),
+        )
+    }
 }
 
 #[derive(Clone, Copy)]