1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
|
use bitvec::prelude::*;
use std::fmt;
use std::ops::{Index, IndexMut};
/// 2D buffer of monochrome (white/black i.e. true/false) pixels
pub struct PixelBuffer {
pub buffer: BitVec,
pub width: usize,
pub height: usize,
}
impl PixelBuffer {
pub fn new(width: usize, height: usize) -> Self {
let mut buffer = BitVec::with_capacity(width * height);
buffer.resize(width * height, false);
PixelBuffer {
buffer,
width,
height,
}
}
pub fn fill_rect(&mut self, x: usize, y: usize, width: usize, height: usize) {
for i in x..(x + width) {
for j in y..(y + height) {
self[i].set(j, true);
}
}
}
}
impl Index<usize> for PixelBuffer {
type Output = BitSlice;
fn index(&self, column: usize) -> &Self::Output {
&self.buffer[(column * self.height)..((column + 1) * self.height)]
}
}
impl IndexMut<usize> for PixelBuffer {
fn index_mut(&mut self, column: usize) -> &mut Self::Output {
&mut self.buffer[(column * self.height)..((column + 1) * self.height)]
}
}
impl fmt::Display for PixelBuffer {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
let mut result = String::new();
for y in 0..self.height {
for x in 0..self.width {
result.push(if self[x][y] { '█' } else { ' ' })
}
result.push('\n')
}
write!(f, "{}", result)
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn access_default() {
let pixel_buffer = PixelBuffer::new(2, 3);
assert!(pixel_buffer[0][0] == false);
}
#[test]
fn mutate() {
let mut pixel_buffer = PixelBuffer::new(2, 3);
pixel_buffer[1].set(2, true);
assert!(pixel_buffer[1][2] == true);
}
#[test]
#[should_panic]
fn access_out_of_bounds() {
let pixel_buffer = PixelBuffer::new(10, 20);
assert!(pixel_buffer[10][0] == false);
}
#[test]
fn print() {
let mut pixel_buffer = PixelBuffer::new(3, 3);
pixel_buffer[1].set(1, true);
let result = format!("{}", pixel_buffer);
assert!(result == " \n █ \n \n");
}
#[test]
fn rect() {
let mut pixel_buffer = PixelBuffer::new(5, 3);
pixel_buffer.fill_rect(1, 0, 2, 2);
let result = format!("{}", pixel_buffer);
assert!(result == " ██ \n ██ \n \n");
}
}
|
