--- a/rust/landgen/src/outline.rs Fri Nov 02 23:33:22 2018 +0300
+++ b/rust/landgen/src/outline.rs Fri Nov 02 22:59:22 2018 +0100
@@ -46,6 +46,13 @@
self.islands.iter().map(|i| i.len()).sum::<usize>() + self.fill_points.len()
}
+ pub fn iter(&self) -> impl Iterator<Item = &Point> {
+ self.islands
+ .iter()
+ .flat_map(|i| i.iter())
+ .chain(self.fill_points.iter())
+ }
+
pub fn iter_mut(&mut self) -> impl Iterator<Item = &mut Point> {
self.islands
.iter_mut()
@@ -56,8 +63,44 @@
fn divide_edge<I: Iterator<Item = u32>>(
&self,
segment: Line,
+ distance_divisor: u32,
random_numbers: &mut I,
) -> Option<Point> {
+ #[inline]
+ fn intersect(p: &Point, m: &Point, p1: &Point, p2: &Point) -> bool {
+ let t1 = (m.x - p1.x) * p.y - p.x * (m.y - p1.y);
+ let t2 = (m.x - p2.x) * p.y - p.x * (m.y - p2.y);
+
+ (t1 > 0) != (t2 > 0)
+ }
+
+ #[inline]
+ fn solve_intersection(p: &Point, m: &Point, s: &Point, e: &Point) -> Option<(i32, u32)> {
+ let f = *e - *s;
+ let aqpb = (p.x * f.y - f.x * p.y) as i64;
+
+ if aqpb != 0 {
+ let iy = ((((s.x - m.x) as i64 * p.y as i64 + m.y as i64 * p.x as i64)
+ * f.y as i64
+ - s.y as i64 * f.x as i64 * p.y as i64)
+ / aqpb) as i32;
+ let ix = if p.y.abs() > f.y.abs() {
+ (iy - m.y) * p.x / p.y + m.x
+ } else {
+ (iy - s.y) * f.x / f.y + s.x
+ };
+
+ let intersection_point = Point::new(ix, iy);
+ let diff_point = *m - intersection_point;
+ let d = diff_point.integral_norm();
+ let t = p.y * diff_point.y + p.x * diff_point.x;
+
+ Some((t, d))
+ } else {
+ None
+ }
+ }
+
let min_distance = 40;
// new point should fall inside this box
let map_box = self.play_box.with_margin(min_distance);
@@ -125,11 +168,71 @@
}
// now go through all other segments
+ for s in self.segments_iter() {
+ if s != segment {
+ if intersect(&p, &mid_point, &s.start, &s.end) {
+ if let Some((t, d)) = solve_intersection(&p, &mid_point, &s.start, &s.end) {
+ if t > 0 {
+ dist_left = min(d, dist_left);
+ } else {
+ dist_right = min(d, dist_right);
+ }
+ }
+ }
+ }
+ }
- None
+ // go through all points, including fill points
+ for pi in self.iter() {
+ if *pi != segment.start && *pi != segment.end {
+ if intersect(&p, &pi, &segment.start, &segment.end) {
+ // ray from segment.start
+ if let Some((t, d)) = solve_intersection(&p, &mid_point, &segment.start, &pi) {
+ if t > 0 {
+ dist_left = min(d, dist_left);
+ } else {
+ dist_right = min(d, dist_right);
+ }
+ }
+
+ // ray from segment.end
+ if let Some((t, d)) = solve_intersection(&p, &mid_point, &segment.end, &pi) {
+ if t > 0 {
+ dist_left = min(d, dist_left);
+ } else {
+ dist_right = min(d, dist_right);
+ }
+ }
+ }
+ }
+ }
+
+ let max_dist = p.integral_norm() * 100 / distance_divisor;
+ dist_left = min(dist_left, max_dist);
+ dist_right = min(dist_right, max_dist);
+
+ if dist_right + dist_left < min_distance as u32 * 2 + 10 {
+ // limits are too narrow, just divide
+ Some(mid_point)
+ } else {
+ // select distance within [-dist_left; dist_right], keeping min_distance in mind
+ let d = -(dist_left as i32)
+ + min_distance
+ + random_numbers.next().unwrap() as i32
+ % (dist_right as i32 + dist_left as i32 - min_distance * 2);
+
+ Some(Point::new(
+ mid_point.x + p.x * d / distance_divisor as i32,
+ mid_point.y + p.y * d / distance_divisor as i32,
+ ))
+ }
}
- fn divide_edges<I: Iterator<Item = u32>>(&mut self, random_numbers: &mut I) {
+ fn divide_edges<I: Iterator<Item = u32>>(
+ &mut self,
+ distance_divisor: u32,
+ random_numbers: &mut I,
+ ) {
for is in 0..self.islands.len() {
let mut i = 0;
let mut segment;
@@ -151,7 +254,8 @@
segment = Line::new(island[i], end_point);
}
- if let Some(new_point) = self.divide_edge(segment, random_numbers) {
+ if let Some(new_point) = self.divide_edge(segment, distance_divisor, random_numbers)
+ {
self.islands[is].insert(i + 1, new_point);
i += 2;
} else {
@@ -161,14 +265,16 @@
}
}
- pub fn bezierize(&mut self) {
- unimplemented!()
- }
+ pub fn bezierize(&mut self) {}
- pub fn distort<I: Iterator<Item = u32>>(&mut self, random_numbers: &mut I) {
+ pub fn distort<I: Iterator<Item = u32>>(
+ &mut self,
+ distance_divisor: u32,
+ random_numbers: &mut I,
+ ) {
loop {
let old_len = self.total_len();
- self.divide_edges(random_numbers);
+ self.divide_edges(distance_divisor, random_numbers);
if self.total_len() == old_len {
break;
@@ -193,15 +299,15 @@
}
pub fn mirror(&mut self) {
- let width = self.size.width as i32;
- self.iter_mut()
- .for_each(|p| p.x = width - 1 - p.x);
+ let r = self.size.width as i32 - 1;
+
+ self.iter_mut().for_each(|p| p.x = r - p.x);
}
pub fn flip(&mut self) {
- let height = self.size.height as i32;
- self.iter_mut()
- .for_each(|p| p.y = height - 1 - p.y);
+ let t = self.size.height as i32 - 1;
+
+ self.iter_mut().for_each(|p| p.y = t - p.y);
}
}