--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/rust/land2d/Cargo.toml Sun Oct 14 23:17:47 2018 +0200
@@ -0,0 +1,7 @@
+[package]
+name = "land2d"
+version = "0.1.0"
+authors = ["Andrey Korotaev <a.korotaev@hedgewars.org>"]
+
+[dependencies]
+vec2d = { path = "../vec2d" }
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/rust/land2d/src/lib.rs Sun Oct 14 23:17:47 2018 +0200
@@ -0,0 +1,101 @@
+extern crate vec2d;
+
+use std::cmp;
+
+pub struct Land2D<T> {
+ pixels: vec2d::Vec2D<T>,
+ width_mask: usize,
+ height_mask: usize,
+}
+
+impl<T: Default + Copy> Land2D<T> {
+ pub fn new(width: usize, height: usize) -> Self {
+ assert!(width.is_power_of_two());
+ assert!(height.is_power_of_two());
+
+ Self {
+ pixels: vec2d::Vec2D::new(width, height, T::default()),
+ width_mask: !(width - 1),
+ height_mask: !(height - 1),
+ }
+ }
+
+ #[inline]
+ fn is_valid_coordinate(&self, x: i32, y: i32) -> bool {
+ (x as usize & self.width_mask) == 0 && (y as usize & self.height_mask) == 0
+ }
+
+ #[inline]
+ pub fn map<U, F: FnOnce(&mut T) -> U>(&mut self, y: i32, x: i32, f: F) {
+ if self.is_valid_coordinate(x, y) {
+ self.pixels.get_mut(y as usize, x as usize).map(f);
+ }
+ }
+
+ pub fn draw_line(&mut self, x1: i32, y1: i32, x2: i32, y2: i32, value: T) {
+ let mut e_x: i32 = 0;
+ let mut e_y: i32 = 0;
+ let mut d_x: i32 = x2 - x1;
+ let mut d_y: i32 = y2 - y1;
+
+ let s_x: i32;
+ let s_y: i32;
+
+ if d_x > 0 {
+ s_x = 1;
+ } else if d_x < 0 {
+ s_x = -1;
+ d_x = -d_x;
+ } else {
+ s_x = d_x;
+ }
+
+ if d_y > 0 {
+ s_y = 1;
+ } else if d_y < 0 {
+ s_y = -1;
+ d_y = -d_y;
+ } else {
+ s_y = d_y;
+ }
+
+ let d = cmp::max(d_x, d_y);
+
+ let mut x = x1;
+ let mut y = y1;
+
+ for _i in 0..=d {
+ e_x += d_x;
+ e_y += d_y;
+
+ if e_x > d {
+ e_x -= d;
+ x += s_x;
+ }
+ if e_y > d {
+ e_y -= d;
+ y += s_y;
+ }
+
+ self.map(y, x, |p| *p = value);
+ }
+ }
+}
+
+#[cfg(test)]
+mod tests {
+ use super::*;
+
+ #[test]
+ fn basics() {
+ let l:Land2D<u8> = Land2D::new(32, 64);
+
+ 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));
+ }
+
+}