chunkgen 0.2.0

Minecraft world generation library
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130

use shulkr::util::Key;
use shulkr::world::block::{Block, BlockState, Properties};

use shulkr::util::Direction;

use crate::util::rng::RandomSource;
use crate::world::worldgen::region::WorldGenRegion;
use shulkr::util::BlockPosition;

const SUPPORTS_CHORUS_PLANT: Key = Key::const_vanilla("supports_chorus_plant");

fn all_neighbors_empty(
    region: &WorldGenRegion<'_>,
    pos: BlockPosition,
    ignore: Option<Direction>,
) -> bool {
    for direction in Direction::HORIZONTAL {
        if Some(direction) != ignore && !region.get_block(pos.relative(direction)).is_air() {
            return false;
        }
    }
    true
}

fn is_plant_or_flower(region: &WorldGenRegion<'_>, pos: BlockPosition) -> bool {
    let block = region.get_block(pos).as_block();
    matches!(block, Block::CHORUS_PLANT | Block::CHORUS_FLOWER)
}

fn supports_chorus_plant(region: &WorldGenRegion<'_>, pos: BlockPosition) -> bool {
    region
        .get_block(pos)
        .as_block()
        .has_tag(&SUPPORTS_CHORUS_PLANT)
}

fn state_with_connections(region: &WorldGenRegion<'_>, pos: BlockPosition) -> BlockState {
    let down = pos.below();
    let down_supported = is_plant_or_flower(region, down) || supports_chorus_plant(region, down);

    Block::CHORUS_PLANT
        .default_state()
        .with(Properties::DOWN, down_supported)
        .with(Properties::UP, is_plant_or_flower(region, pos.above()))
        .with(Properties::NORTH, is_plant_or_flower(region, pos.north()))
        .with(Properties::EAST, is_plant_or_flower(region, pos.east()))
        .with(Properties::SOUTH, is_plant_or_flower(region, pos.south()))
        .with(Properties::WEST, is_plant_or_flower(region, pos.west()))
}

fn grow_tree_recursive(
    region: &WorldGenRegion<'_>,
    random: &mut RandomSource,
    current: BlockPosition,
    start_pos: BlockPosition,
    max_horizontal_spread: i32,
    depth: i32,
) {
    let mut height = random.next_i32_bounded(4) + 1;
    if depth == 0 {
        height += 1;
    }

    for i in 0..height {
        let target = current.above_n(i + 1);
        if !all_neighbors_empty(region, target, None) {
            return;
        }

        region.set_block(target, state_with_connections(region, target));
        let below = target.below();
        region.set_block(below, state_with_connections(region, below));
    }

    let mut placed_stem = false;
    if depth < 4 {
        let mut stems = random.next_i32_bounded(4);
        if depth == 0 {
            stems += 1;
        }

        for _ in 0..stems {
            let direction = Direction::HORIZONTAL[random.next_i32_bounded(4) as usize];
            let target = current.above_n(height).relative(direction);
            let below = target.below();
            if (target.x() - start_pos.x()).abs() < max_horizontal_spread
                && (target.z() - start_pos.z()).abs() < max_horizontal_spread
                && region.get_block(target).is_air()
                && region.get_block(below).is_air()
                && all_neighbors_empty(region, target, Some(direction.opposite()))
            {
                placed_stem = true;
                region.set_block(target, state_with_connections(region, target));
                let opposite_pos = target.relative(direction.opposite());
                region.set_block(opposite_pos, state_with_connections(region, opposite_pos));
                grow_tree_recursive(
                    region,
                    random,
                    target,
                    start_pos,
                    max_horizontal_spread,
                    depth + 1,
                );
            }
        }
    }

    if !placed_stem {
        region.set_block(
            current.above_n(height),
            Block::CHORUS_FLOWER
                .default_state()
                .with(Properties::AGE_5, 5),
        );
    }
}

pub fn place(
    region: &WorldGenRegion<'_>,
    random: &mut RandomSource,
    origin: BlockPosition,
) -> bool {
    if region.get_block(origin).is_air() && supports_chorus_plant(region, origin.below()) {
        region.set_block(origin, state_with_connections(region, origin));
        grow_tree_recursive(region, random, origin, origin, 8, 0);
        true
    } else {
        false
    }
}