use super::super::Image;
pub fn pad<T: Image>(
top: usize,
bottom: usize,
left: usize,
right: usize,
padding: T::Pixel,
frame: T
) -> Pad<T> {
Pad { top, bottom, left, right, padding, frame }
}
#[doc(hidden)]
pub struct Pad<T: Image> {
top: usize,
bottom: usize,
left: usize,
right: usize,
padding: T::Pixel,
frame: T
}
impl<T: Image> Image for Pad<T>
where T::Pixel: Clone {
type Pixel = T::Pixel;
fn width(&self) -> usize { self.left + self.frame.width() + self.right }
fn height(&self) -> usize { self.top + self.frame.height() + self.bottom }
unsafe fn pixel(&self, mut x: usize, mut y: usize) -> Self::Pixel {
if x < self.left || y < self.top {
self.padding.clone()
} else {
x -= self.left;
y -= self.top;
if x < self.frame.width() && y < self.frame.height() {
self.frame.pixel(x, y)
} else {
self.padding.clone()
}
}
}
}