feat: take PixelRead and WindowedDrawTarget from embedded-draw-target

Both traits were defined here, so a buffer implementing them satisfied this
crate and nothing else -- a 3D rasterizer or an application needing the same
readback had to implement a second, identical trait.

Re-export them from embedded-draw-target instead. The paths and signatures are
unchanged, so existing implementors and call sites are unaffected, but the
trait identity is now shared across the ecosystem: one buffer can serve this
crate's alpha compositor, a rasterizer's anti-aliasing, and plain
embedded-graphics drawing at once.

Author: leftger

Cargo.lock

@@ -1,6 +1,6 @@
 [package]
 name = "embedded-gui"
-version = "0.1.5"
+version = "0.1.6"
 edition = "2024"
 rust-version = "1.87"
 authors = ["Gerzain Mata <leftger@gmail.com>"]
@@ -51,6 +51,7 @@ embassy = ["embassy-time", "dep:embassy-sync"]
 
 [dependencies]
 embedded-graphics-core = "0.4.1"
+embedded-draw-target = { version = "0.1", default-features = false }
 embedded-graphics-framebuf = "0.3"
 critical-section = "1.1"
 heapless = "0.9"

Cargo.toml

@@ -360,20 +360,19 @@ pub enum BlendMode {
 /// Implementing `PixelRead` additionally unlocks the `*_true_alpha` methods,
 /// which composite against the destination's actual current contents
 /// instead of dithering.
-pub trait PixelRead: DrawTarget {
-    fn get_pixel(&self, point: Point) -> Self::Color;
-}
+///
+/// Re-exported from [`embedded_draw_target`] so that a buffer implementing it
+/// once is accepted by every crate in the ecosystem that needs readback,
+/// rather than by this one alone.
+pub use embedded_draw_target::PixelRead;
 
 /// Capability trait for hardware display controllers (e.g. ST7789, ILI9341, SSD1306)
 /// supporting direct column/row address window setting (`set_address_window`).
 /// Allows rendering dirty regions by transmitting SPI/DMA transfers exclusively to
 /// the target sub-window instead of the full screen.
-pub trait WindowedDrawTarget: DrawTarget {
-    fn set_window(
-        &mut self,
-        area: &embedded_graphics_core::primitives::Rectangle,
-    ) -> Result<(), Self::Error>;
-}
+///
+/// Re-exported from [`embedded_draw_target`].
+pub use embedded_draw_target::WindowedDrawTarget;
 
 /// Pixel-plotting policy for a [`RenderCtx`]. Selected by the ctx's `C` type
 /// parameter so the *same* drawing calls composite differently depending on