render: make surfaces own rectangles, to drop a clone

src/render.rs

@@ -30,7 +30,7 @@ pub trait Shader: Send + Sync {
 pub trait Surfaces: Send + Sync {
     type Surface: Surface;
     type Error: Debug;
-    fn new_surface(&mut self, area: &Rectangle<Virtual>) -> Result<Self::Surface, Self::Error>;
+    fn new_surface(&mut self, area: Rectangle<Virtual>) -> Result<Self::Surface, Self::Error>;
     fn render_to<S: Sample>(&self, output: &mut S, frame: usize);
 }
 
@@ -38,7 +38,7 @@ pub trait Surface: Send + Sync {
     fn set_shader(&mut self, shader: Box<dyn Shader>);
     fn clear_shader(&mut self);
 
-    fn set_rect(&mut self, rect: &Rectangle<Virtual>);
+    fn set_rect(&mut self, rect: Rectangle<Virtual>);
     fn set_opacity(&mut self, opacity: u8);
 }