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#![warn(missing_docs)]
extern crate line_drawing;
extern crate rusttype;
#[macro_use]
extern crate bitflags;
pub mod line;
pub mod shapes;
pub mod text;
pub trait Drawable {
fn draw(&self, canvas: &mut Canvas);
}
pub struct Canvas<'a> {
pub buffer: &'a mut [u8],
pub width: usize,
pub height: usize,
pub stride: usize,
pub pixel_size: usize,
}
impl<'a> Canvas<'a> {
pub fn new(buffer: &'a mut [u8], width: usize, height: usize, stride: usize) -> Canvas<'a> {
assert!(
stride % width == 0,
"Incorrect Dimensions - Stride is not a multiple of width"
);
assert!(buffer.len() == stride * height);
let pixel_size = stride / width;
Canvas {
buffer,
width,
height,
stride,
pixel_size,
}
}
pub fn draw<D: Drawable>(&mut self, drawable: &D) {
drawable.draw(self);
}
pub fn draw_point(&mut self, x: usize, y: usize, color: [u8; 4]) {
for c in 0..3 {
let alpha = f32::from(color[3]) / 255.0;
let color_diff = (color[c] as isize
- self.buffer[self.stride * y + self.pixel_size * x + c] as isize)
as f32
* alpha;
let new_color = (f32::from(self.buffer[self.stride * y + self.pixel_size * x + c])
+ color_diff) as u8;
self.buffer[self.stride * y + self.pixel_size * x + c] = new_color as u8;
}
self.buffer[self.stride * y + self.pixel_size * x + 3] = 255 as u8;
}
pub fn clear(&mut self) {
for i in 0..self.width * self.height * 4 {
self.buffer[i] = 0x00;
}
}
}