use itertools::Itertools;
use std::cmp::min;
use integral_geometry::{Line, Ray, Point, Polygon, Rect, Size};
use land2d::Land2D;
use crate::outline_template::OutlineTemplate;
pub struct OutlinePoints {
pub islands: Vec<Polygon>,
pub fill_points: Vec<Point>,
pub size: Size,
pub play_box: Rect,
intersections_box: Rect,
}
impl OutlinePoints {
pub fn from_outline_template<I: Iterator<Item = u32>>(
outline_template: &OutlineTemplate,
play_box: Rect,
size: Size,
random_numbers: &mut I,
) -> Self {
Self {
play_box,
size,
islands: outline_template
.islands
.iter()
.map(|i| {
i.iter()
.zip(random_numbers.tuples())
.map(|(rect, (rnd_a, rnd_b))| {
play_box.top_left() + rect.quotient(rnd_a as usize, rnd_b as usize)
})
.collect::<Vec<_>>()
.into()
})
.collect(),
fill_points: outline_template.fill_points.clone(),
intersections_box: Rect::at_origin(size)
.with_margin(size.to_square().width as i32 * -2),
}
}
pub fn total_len(&self) -> usize {
self.islands.iter().map(|i| i.edges_count()).sum::<usize>() + self.fill_points.len()
}
pub fn iter(&self) -> impl Iterator<Item = &Point> {
self.islands
.iter()
.flat_map(|p| p.iter())
.chain(self.fill_points.iter())
}
pub fn iter_mut(&mut self) -> impl Iterator<Item = &mut Point> {
self.islands
.iter_mut()
.flat_map(|i| i.iter_mut())
.chain(self.fill_points.iter_mut())
}
fn divide_edge<I: Iterator<Item = u32>>(
&self,
segment: Line,
distance_divisor: u32,
random_numbers: &mut I,
) -> Option<Point> {
#[inline]
fn intersects(ray: &Ray, edge: &Line) -> bool {
ray.orientation(edge.start) != ray.orientation(edge.end)
}
#[inline]
fn solve_intersection(
intersections_box: &Rect,
ray: &Ray,
edge: &Line
) -> Option<(i32, u32)>
{
let edge_dir = edge.scaled_direction();
let aqpb = ray.direction.cross(edge_dir) as i64;
if aqpb != 0 {
let mut iy =
((((edge.start.x - ray.start.x) as i64 * ray.direction.y as i64
+ ray.start.y as i64 * ray.direction.x as i64)
* edge_dir.y as i64
- edge.start.y as i64 * edge_dir.x as i64 * ray.direction.y as i64)
/ aqpb) as i32;
// is there better way to do it?
if iy < intersections_box.top() {
iy = intersections_box.top();
} else if iy > intersections_box.bottom() {
iy = intersections_box.bottom();
}
let ix = if ray.direction.y.abs() > edge_dir.y.abs() {
ray.start.x + ray.direction.cotangent_mul(iy - ray.start.y)
} else {
edge.start.x + edge_dir.cotangent_mul(iy - edge.start.y)
};
let intersection_point = Point::new(ix, iy).clamp(intersections_box);
let diff_point = ray.start - intersection_point;
let t = ray.direction.dot(diff_point);
if diff_point.max_norm() >= std::i16::MAX as i32 {
Some((t, std::i32::MAX as u32))
} else {
let d = diff_point.integral_norm();
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);
let normal = segment.scaled_normal();
let normal_len = normal.integral_norm();
let mid_point = segment.center();
if (normal_len < min_distance as u32 * 3) || !map_box.contains_inside(mid_point) {
return None;
}
let normal_ray = Ray::new(mid_point, normal);
let mut dist_left = (self.size.width + self.size.height) as u32;
let mut dist_right = dist_left;
// find distances to map borders
if normal.x != 0 {
// where the normal line intersects the left map border
let left_intersection = Point::new(
map_box.left(),
mid_point.y + normal.tangent_mul(map_box.left() - mid_point.x),
);
dist_left = (mid_point - left_intersection).integral_norm();
// same for the right border
let right_intersection = Point::new(
map_box.right(),
mid_point.y + normal.tangent_mul(map_box.right() - mid_point.x) ,
);
dist_right = (mid_point - right_intersection).integral_norm();
if normal.x > 0 {
std::mem::swap(&mut dist_left, &mut dist_right);
}
}
if normal.y != 0 {
// where the normal line intersects the top map border
let top_intersection = Point::new(
mid_point.x + normal.cotangent_mul(map_box.top() - mid_point.y),
map_box.top(),
);
let dl = (mid_point - top_intersection).integral_norm();
// same for the bottom border
let bottom_intersection = Point::new(
mid_point.x + normal.cotangent_mul(map_box.bottom() - mid_point.y),
map_box.bottom(),
);
let dr = (mid_point - bottom_intersection).integral_norm();
if normal.y < 0 {
dist_left = min(dist_left, dl);
dist_right = min(dist_right, dr);
} else {
dist_left = min(dist_left, dr);
dist_right = min(dist_right, dl);
}
}
// now go through all other segments
for s in self.segments_iter() {
if s != segment {
if intersects(&normal_ray, &s) {
if let Some((t, d)) =
solve_intersection(&self.intersections_box, &normal_ray, &s)
{
if t > 0 {
dist_right = min(dist_right, d);
} else {
dist_left = min(dist_left, d);
}
}
}
}
}
// go through all points, including fill points
for pi in self.iter().cloned() {
if pi != segment.start && pi != segment.end {
if intersects(&pi.ray_with_dir(normal), &segment) {
// ray from segment.start
if let Some((t, d)) = solve_intersection(
&self.intersections_box, &normal_ray, &segment.start.line_to(pi),
) {
if t > 0 {
dist_right = min(dist_right, d);
} else {
dist_left = min(dist_left, d);
}
}
// ray from segment.end
if let Some((t, d)) = solve_intersection(
&self.intersections_box, &normal_ray, &segment.end.line_to(pi)
) {
if t > 0 {
dist_right = min(dist_right, d);
} else {
dist_left = min(dist_left, d);
}
}
}
}
}
let max_dist = normal_len * 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_right; dist_left], keeping min_distance in mind
let d = -(dist_right as i32)
+ min_distance
+ random_numbers.next().unwrap() as i32
% (dist_right as i32 + dist_left as i32 - min_distance * 2);
Some(mid_point + normal * d / normal_len as i32)
}
}
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;
while i < self.islands[is].edges_count() {
let segment = self.islands[is].get_edge(i);
if let Some(new_point) = self.divide_edge(segment, distance_divisor, random_numbers)
{
self.islands[is].split_edge(i, new_point);
i += 2;
} else {
i += 1;
}
}
}
}
pub fn bezierize(&mut self, segments_number: u32) {
for island in &mut self.islands {
island.bezierize(segments_number);
}
}
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(distance_divisor, random_numbers);
if self.total_len() == old_len {
break;
}
}
}
pub fn draw<T: Copy + PartialEq>(&self, land: &mut Land2D<T>, value: T) {
for segment in self.segments_iter() {
land.draw_line(segment, value);
}
}
fn segments_iter<'a>(&'a self) -> impl Iterator<Item = Line> + 'a {
self.islands.iter().flat_map(|p| p.iter_edges())
}
pub fn mirror(&mut self) {
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 t = self.size.height as i32 - 1;
self.iter_mut().for_each(|p| p.y = t - p.y);
}
}
#[test()]
fn points_test() {
let size = Size::square(100);
let mut points = OutlinePoints {
islands: vec![
Polygon::new(&[Point::new(0, 0), Point::new(20, 0), Point::new(30, 30)]),
Polygon::new(&[Point::new(10, 15), Point::new(15, 20), Point::new(20, 15)]),
],
fill_points: vec![Point::new(1, 1)],
play_box: Rect::at_origin(size).with_margin(10),
size: Size::square(100),
intersections_box: Rect::at_origin(size),
};
let segments: Vec<Line> = points.segments_iter().collect();
assert_eq!(
segments.first(),
Some(&Line::new(Point::new(0, 0), Point::new(20, 0)))
);
assert_eq!(
segments.last(),
Some(&Line::new(Point::new(20, 15), Point::new(10, 15)))
);
points.iter_mut().for_each(|p| p.x = 2);
assert_eq!(points.fill_points[0].x, 2);
assert_eq!(points.islands[0].get_edge(0).start.x, 2);
}