Files
phos-neo/engine/world_generation/src/hex_utils.rs
2024-11-06 22:42:01 -05:00

313 lines
7.4 KiB
Rust

use std::fmt::Display;
use crate::prelude::Chunk;
use bevy::prelude::*;
use serde::{Deserialize, Serialize};
pub const OUTER_RADIUS: f32 = 1.;
pub const INNER_RADIUS: f32 = OUTER_RADIUS * (SQRT_3 / 2.);
pub const SHORT_DIAGONAL: f32 = 1. * SQRT_3;
pub const LONG_DIAGONAL: f32 = 2. * OUTER_RADIUS;
const SQRT_3: f32 = 1.7320508076;
pub fn offset3d_to_world(offset: Vec3) -> Vec3 {
let x = (offset.x + (offset.z * 0.5) - (offset.z / 2.).floor()) * (INNER_RADIUS * 2.);
return Vec3::new(x, offset.y, offset.z * OUTER_RADIUS * 1.5);
}
pub fn offset_to_world(offset: IVec2, height: f32) -> Vec3 {
let off = offset.as_vec2();
let x = (off.x + (off.y * 0.5) - (off.y / 2.).floor()) * (INNER_RADIUS * 2.);
return Vec3::new(x, height, off.y * OUTER_RADIUS * 1.5);
}
pub fn offset_to_hex(offset: IVec2) -> IVec3 {
let mut v = IVec3 {
x: offset.x - (offset.y / 2),
y: offset.y,
z: 0,
};
v.z = -v.x - v.y;
return v;
}
pub fn offset_to_index(offset: IVec2, width: usize) -> usize {
return offset.x as usize + offset.y as usize * width;
}
pub fn snap_to_hex_grid(world_pos: Vec3) -> Vec3 {
return offset_to_world(world_to_offset_pos(world_pos), world_pos.y);
}
pub fn world_to_offset_pos(world_pos: Vec3) -> IVec2 {
let offset = world_pos.z / (OUTER_RADIUS * 3.);
let x = (world_pos.x / (INNER_RADIUS * 2.)) - offset;
let z = -world_pos.x - offset;
let ix = x.round() as i32;
let iz = z.round() as i32;
let ox = ix + iz / 2;
let oz = iz;
return IVec2::new(ox, oz);
}
pub fn tile_to_world_distance(dist: u32) -> f32 {
return dist as f32 * (2. * INNER_RADIUS);
}
pub fn get_tile_count_in_range(radius: usize) -> usize {
return 1 + 3 * (radius + 1) * radius;
}
#[derive(Default, Debug, Clone, Copy, Eq, PartialEq, Serialize, Deserialize, Hash)]
pub struct HexCoord {
pub hex: IVec3,
}
impl Display for HexCoord {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
f.write_fmt(format_args!("HexCoord{}", self.hex))
}
}
impl HexCoord {
pub const DIRECTIONS: [IVec3; 6] = [
IVec3::new(0, 1, -1),
IVec3::new(1, 0, -1),
IVec3::new(1, -1, 0),
IVec3::new(0, -1, 1),
IVec3::new(-1, 0, 1),
IVec3::new(-1, 1, 0),
];
pub const ZERO: HexCoord = HexCoord { hex: IVec3::ZERO };
pub fn new(x: i32, z: i32) -> Self {
return HexCoord {
hex: IVec3::new(x, z, -x - z),
};
}
pub fn from_hex(hex: IVec2) -> Self {
return HexCoord {
hex: IVec3::new(hex.x, hex.y, -hex.x - hex.y),
};
}
pub fn from_grid_pos(x: usize, z: usize) -> Self {
return HexCoord::new(x as i32 - (z as i32 / 2), z as i32);
}
pub fn from_offset(offset_pos: IVec2) -> Self {
return HexCoord {
hex: offset_to_hex(offset_pos),
};
}
pub fn from_world_pos(world_pos: Vec3) -> Self {
let offset = world_pos.z / (OUTER_RADIUS * 3.);
let mut x = world_pos.x / (INNER_RADIUS * 2.);
let mut z = -x;
z -= offset;
x -= offset;
let i_x = x.round() as i32;
let i_z = (-x - z).round() as i32;
let offset_pos = IVec2::new(i_x + i_z / 2, i_z);
return Self::from_offset(offset_pos);
}
pub fn is_in_bounds(&self, map_height: usize, map_width: usize) -> bool {
let off = self.to_offset();
if off.x < 0 || off.y < 0 {
return false;
}
if off.x >= map_width as i32 || off.y >= map_height as i32 {
return false;
}
return true;
}
pub fn is_on_chunk_edge(&self) -> bool {
let offset = self.to_offset().rem_euclid(IVec2::splat(Chunk::SIZE as i32));
let e = (Chunk::SIZE - 1) as i32;
return offset.x == 0 || offset.y == 0 || offset.x == e || offset.y == e;
}
pub fn to_chunk_pos(&self) -> IVec2 {
let off = self.to_offset();
return IVec2 {
x: (off.x as f32 / Chunk::SIZE as f32).floor() as i32,
y: (off.y as f32 / Chunk::SIZE as f32).floor() as i32,
};
}
/// Converts this coordinate to it's chunk local equivalent
pub fn to_chunk(&self) -> HexCoord {
let c_pos = self.to_chunk_pos();
let off = self.to_offset();
return HexCoord::from_offset(
(
off.x - (c_pos.x * Chunk::SIZE as i32),
off.y - (c_pos.y * Chunk::SIZE as i32),
)
.into(),
);
}
pub fn to_world(&self, height: f32) -> Vec3 {
return offset_to_world(self.to_offset(), height);
}
pub fn to_offset(&self) -> IVec2 {
return IVec2::new(self.hex.x + (self.hex.y / 2), self.hex.y);
}
/// Convert the current coordiante to an index
pub fn to_index(&self, width: usize) -> usize {
return ((self.hex.x + self.hex.y * width as i32) + (self.hex.y / 2)) as usize;
}
/// Gets the index of this coord in the chunk array.
///
/// [`width`] is in number of chunks
pub fn to_chunk_index(&self, width: usize) -> usize {
let pos = self.to_chunk_pos();
return (pos.x + pos.y * width as i32) as usize;
}
/// Gets the index of this tile in the chunk
pub fn to_chunk_local_index(&self) -> usize {
return self.to_chunk().to_index(Chunk::SIZE);
}
pub fn distance(&self, other: &HexCoord) -> i32 {
return (self.hex.x - other.hex.x).abs() + (self.hex.y - other.hex.y).abs() + (self.hex.z - other.hex.z).abs();
}
pub fn rotate_around(&self, center: &HexCoord, angle: i32) -> HexCoord {
if self == center || angle == 0 {
return self.clone();
}
let mut a = angle % 6;
let mut pc = self.hex - center.hex;
if a > 0 {
for _ in 0..a {
pc = Self::slide_right(pc);
}
} else {
a = a.abs();
for _ in 0..a {
pc = Self::slide_left(pc);
}
}
return HexCoord::from_hex(pc.xy() + center.hex.xy());
}
fn slide_left(hex: IVec3) -> IVec3 {
return (hex * -1).yzx();
}
fn slide_right(hex: IVec3) -> IVec3 {
return (hex * -1).zxy();
}
pub fn scale(&self, dir: i32, radius: usize) -> HexCoord {
let s = Self::DIRECTIONS[(dir % 6) as usize] * radius as i32;
return Self::from_hex(self.hex.xy() + s.xy());
}
pub fn get_neighbor(&self, dir: usize) -> HexCoord {
let d = Self::DIRECTIONS[dir % 6];
return Self::from_hex(self.hex.xy() + d.xy());
}
pub fn get_neighbors(&self) -> [HexCoord; 6] {
return [
self.get_neighbor(0),
self.get_neighbor(1),
self.get_neighbor(2),
self.get_neighbor(3),
self.get_neighbor(4),
self.get_neighbor(5),
];
}
pub fn hex_select(&self, radius: usize, include_center: bool) -> Vec<HexCoord> {
assert!(radius != 0, "Radius cannot be zero");
let mut result = Vec::with_capacity(get_tile_count_in_range(radius));
if include_center {
result.push(*self);
}
for k in 0..(radius + 1) {
let mut p = self.scale(4, k);
for i in 0..6 {
for _j in 0..k {
p = p.get_neighbor(i);
result.push(p);
}
}
}
return result;
}
pub fn hex_select_bounded(
&self,
radius: usize,
include_center: bool,
height: usize,
width: usize,
) -> Vec<HexCoord> {
assert!(radius != 0, "Radius cannot be zero");
let mut result = Vec::with_capacity(get_tile_count_in_range(radius));
if include_center {
if self.is_in_bounds(height, width) {
result.push(*self);
}
}
for k in 0..(radius + 1) {
let mut p = self.scale(4, k);
for i in 0..6 {
for _j in 0..k {
p = p.get_neighbor(i);
if p.is_in_bounds(height, width) {
result.push(p);
}
}
}
}
return result;
}
pub fn select_ring(&self, radius: usize) -> Vec<HexCoord> {
assert!(radius != 0, "Radius cannot be zero");
let mut result = Vec::with_capacity(radius * 6);
let mut p = self.scale(4, radius);
// if radius == 1 {
// result.push(*self);
// return result;
// }
for i in 0..6 {
for _j in 0..radius {
result.push(p);
p = p.get_neighbor(i);
}
}
return result;
}
}