here_be_dragons/src/filter/starting_point.rs
2020-09-22 20:44:54 +02:00

96 lines
2.7 KiB
Rust

//! Add starting point to the map
//!
//! This modifier will try to add starting point by finding the floor title closes
//! to the given point.
//!
//! Example modifier usage:
//! ```
//! use rand::prelude::*;
//! use mapgen::{MapFilter, Map, TileType};
//! use mapgen::filter::starting_point::{AreaStartingPosition, XStart, YStart};
//! use mapgen::geometry::Point;
//!
//! let mut rng = StdRng::seed_from_u64(100);
//! let mut map = Map::new(80, 50);
//! map.set_tile(10, 10, TileType::Floor);
//! let modifier = AreaStartingPosition::new(XStart::LEFT, YStart::TOP);
//! let new_map = modifier.modify_map(&mut rng, &map);
//!
//! assert_eq!(new_map.starting_point, Some(Point::new(10, 10)));
//! ```
//!
use rand::prelude::StdRng;
use crate::MapFilter;
use crate::geometry::Point;
use crate::{Map, TileType};
/// Initial x region position
pub enum XStart { LEFT, CENTER, RIGHT }
/// Initial y region position
pub enum YStart { TOP, CENTER, BOTTOM }
/// Add starting position to the map
pub struct AreaStartingPosition {
x : XStart,
y : YStart
}
impl MapFilter for AreaStartingPosition {
fn modify_map(&self, _: &mut StdRng, map: &Map) -> Map {
self.build(map)
}
}
impl AreaStartingPosition {
/// Create new modifier with given region
pub fn new(x : XStart, y : YStart) -> Box<AreaStartingPosition> {
Box::new(AreaStartingPosition{
x, y
})
}
fn build(&self, map : &Map) -> Map {
let seed_x;
let seed_y;
match self.x {
XStart::LEFT => seed_x = 1,
XStart::CENTER => seed_x = map.width / 2,
XStart::RIGHT => seed_x = map.width - 2
}
match self.y {
YStart::TOP => seed_y = 1,
YStart::CENTER => seed_y = map.height / 2,
YStart::BOTTOM => seed_y = map.height - 2
}
let mut available_floors : Vec<(usize, f32)> = Vec::new();
for (idx, tiletype) in map.tiles.iter().enumerate() {
if *tiletype == TileType::Floor {
available_floors.push(
(
idx,
Point::new(idx % map.width, idx / map.width)
.distance_to(&Point::new(seed_x, seed_y))
)
);
}
}
if available_floors.is_empty() {
panic!("No valid floors to start on");
}
available_floors.sort_by(|a,b| a.1.partial_cmp(&b.1).unwrap());
let start_x = available_floors[0].0 % map.width;
let start_y = available_floors[0].0 / map.width;
let mut new_map = map.clone();
new_map.starting_point = Some(Point::new(start_x, start_y));
new_map
}
}