extern crate integral_geometry;
extern crate vec2d;
use std::cmp;
use std::ops;
use integral_geometry::{ArcPoints, EquidistantPoints, LinePoints, Point};
pub struct Land2D<T> {
pixels: vec2d::Vec2D<T>,
width_mask: usize,
height_mask: usize,
}
impl<T: Copy + PartialEq> Land2D<T> {
pub fn new(width: usize, height: usize, fill_value: T) -> Self {
assert!(width.is_power_of_two());
assert!(height.is_power_of_two());
Self {
pixels: vec2d::Vec2D::new(width, height, fill_value),
width_mask: !(width - 1),
height_mask: !(height - 1),
}
}
#[inline]
pub fn width(&self) -> usize {
self.pixels.width()
}
#[inline]
pub fn height(&self) -> usize {
self.pixels.height()
}
#[inline]
pub fn is_valid_x(&self, x: i32) -> bool {
(x as usize & self.width_mask) == 0
}
#[inline]
pub fn is_valid_y(&self, y: i32) -> bool {
(y as usize & self.height_mask) == 0
}
#[inline]
pub fn is_valid_coordinate(&self, x: i32, y: i32) -> bool {
self.is_valid_x(x) && self.is_valid_y(y)
}
#[inline]
pub fn map<U: Default, F: FnOnce(&mut T) -> U>(&mut self, y: i32, x: i32, f: F) -> U {
if self.is_valid_coordinate(x, y) {
unsafe {
// hey, I just checked that coordinates are valid!
f(self.pixels.get_unchecked_mut(y as usize, x as usize))
}
} else {
U::default()
}
}
#[inline]
pub fn map_point<U: Default, F: FnOnce(&mut T) -> U>(&mut self, point: Point, f: F) -> U {
self.map(point.y, point.x, f)
}
pub fn fill_from_iter<I>(&mut self, i: I, value: T) -> usize
where
I: std::iter::Iterator<Item = Point>,
{
i.map(|p| {
self.map(p.y, p.x, |v| {
*v = value;
1
})
}).count()
}
pub fn draw_line(&mut self, from: Point, to: Point, value: T) -> usize {
self.fill_from_iter(LinePoints::new(from, to), value)
}
pub fn fill(&mut self, start_point: Point, border_value: T, fill_value: T) {
debug_assert!(self.is_valid_coordinate(start_point.x - 1, start_point.y));
debug_assert!(self.is_valid_coordinate(start_point.x, start_point.y));
let mut stack: Vec<(usize, usize, usize, isize)> = Vec::new();
fn push<T: Copy + PartialEq>(
land: &Land2D<T>,
stack: &mut Vec<(usize, usize, usize, isize)>,
xl: usize,
xr: usize,
y: usize,
dir: isize,
) {
let yd = y as isize + dir;
if land.is_valid_coordinate(0, yd as i32) {
stack.push((xl, xr, yd as usize, dir));
}
};
let start_x_l = (start_point.x - 1) as usize;
let start_x_r = start_point.x as usize;
push(
self,
&mut stack,
start_x_l,
start_x_r,
start_point.y as usize,
-1,
);
push(
self,
&mut stack,
start_x_l,
start_x_r,
start_point.y as usize,
1,
);
loop {
let a = stack.pop();
match a {
None => return,
Some(a) => {
let (mut xl, mut xr, y, mut dir) = a;
while xl > 0 && self
.pixels
.get(y, xl)
.map_or(false, |v| *v != border_value && *v != fill_value)
{
xl -= 1;
}
while xr < self.width() - 1 && self
.pixels
.get(y, xr)
.map_or(false, |v| *v != border_value && *v != fill_value)
{
xr += 1;
}
while xl < xr {
while xl <= xr
&& (self.pixels[y][xl] == border_value
|| self.pixels[y][xl] == fill_value)
{
xl += 1;
}
let mut x = xl;
while xl <= xr
&& (self.pixels[y][xl] != border_value
&& self.pixels[y][xl] != fill_value)
{
self.pixels[y][xl] = fill_value;
xl += 1;
}
if x < xl {
push(self, &mut stack, x, xl - 1, y, dir);
push(self, &mut stack, x, xl - 1, y, -dir);
}
}
}
}
}
}
#[inline]
fn fill_circle_line<F: Fn(&mut T) -> usize>(
&mut self,
y: i32,
x_from: i32,
x_to: i32,
f: &F,
) -> usize {
let mut result = 0;
if self.is_valid_y(y) {
for i in cmp::min(x_from, 0) as usize..cmp::max(x_to as usize, self.width() - 1) {
unsafe {
// coordinates are valid at this point
result += f(self.pixels.get_unchecked_mut(y as usize, i));
}
}
}
result
}
#[inline]
fn fill_circle_lines<F: Fn(&mut T) -> usize>(
&mut self,
x: i32,
y: i32,
dx: i32,
dy: i32,
f: &F,
) -> usize {
self.fill_circle_line(y + dy, x - dx, x + dx, f)
+ self.fill_circle_line(y - dy, x - dx, x + dx, f)
+ self.fill_circle_line(y + dx, x - dy, x + dy, f)
+ self.fill_circle_line(y - dx, x - dy, x + dy, f)
}
pub fn change_round<F: Fn(&mut T) -> usize>(
&mut self,
x: i32,
y: i32,
radius: i32,
f: F,
) -> usize {
ArcPoints::new(radius)
.map(&mut |p: Point| self.fill_circle_lines(x, y, p.x, p.y, &f))
.sum()
}
pub fn draw_thick_line(&mut self, from: Point, to: Point, radius: i32, value: T) -> usize {
let mut result = 0;
for point in LinePoints::new(from, to) {
for vector in ArcPoints::new(radius) {
for delta in EquidistantPoints::new(vector) {
self.map_point(point + delta, |p| {
if *p != value {
*p = value;
result += 1;
}
})
}
}
}
result
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn basics() {
let l: Land2D<u8> = Land2D::new(32, 64, 0);
assert!(l.is_valid_coordinate(0, 0));
assert!(!l.is_valid_coordinate(-1, -1));
assert!(l.is_valid_coordinate(31, 63));
assert!(!l.is_valid_coordinate(32, 63));
assert!(!l.is_valid_coordinate(31, 64));
}
#[test]
fn fill() {
let mut l: Land2D<u8> = Land2D::new(128, 128, 0);
l.draw_line(Point::new(0, 0), Point::new(32, 96), 1);
l.draw_line(Point::new(32, 96), Point::new(64, 32), 1);
l.draw_line(Point::new(64, 32), Point::new(96, 80), 1);
l.draw_line(Point::new(96, 80), Point::new(128, 0), 1);
l.draw_line(Point::new(0, 128), Point::new(64, 96), 1);
l.draw_line(Point::new(128, 128), Point::new(64, 96), 1);
l.fill(Point::new(32, 32), 1, 2);
l.fill(Point::new(16, 96), 1, 3);
l.fill(Point::new(60, 100), 1, 4);
assert_eq!(l.pixels[0][0], 1);
assert_eq!(l.pixels[96][64], 1);
assert_eq!(l.pixels[40][32], 2);
assert_eq!(l.pixels[40][96], 2);
assert_eq!(l.pixels[5][0], 3);
assert_eq!(l.pixels[120][0], 3);
assert_eq!(l.pixels[5][127], 3);
assert_eq!(l.pixels[120][127], 3);
assert_eq!(l.pixels[35][64], 3);
assert_eq!(l.pixels[120][20], 4);
assert_eq!(l.pixels[120][100], 4);
assert_eq!(l.pixels[100][64], 4);
}
}