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
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153

use serde::Deserialize;

use crate::util::hash_set::JavaHashSet;
use crate::util::rng::RandomSource;
use crate::util::value_providers::int::IntProvider;
use crate::world::worldgen::feature::features::mark_above_for_post_processing;
use crate::world::worldgen::feature::features::tree;
use crate::world::worldgen::feature::state_provider::ProviderHolder;
use crate::world::worldgen::feature::treedecorators::{TreeDecorator, TreeDecoratorContext};
use crate::world::worldgen::region::WorldGenRegion;
use shulkr::util::BlockPosition;
use shulkr::util::Direction;
use shulkr::world::block::Properties;
use std::iter;

#[derive(Debug, Deserialize)]
pub struct FallenTreeConfig {
    pub trunk_provider: ProviderHolder,
    pub log_length: IntProvider,
    pub stump_decorators: Vec<TreeDecorator>,
    pub log_decorators: Vec<TreeDecorator>,
}

pub fn place(
    region: &WorldGenRegion<'_>,
    random: &mut RandomSource,
    origin: BlockPosition,
    config: &FallenTreeConfig,
) -> bool {
    place_stump(region, random, origin, config);

    let direction = Direction::HORIZONTAL[random.next_i32_bounded(4) as usize];
    let log_length = config.log_length.sample(random) - 2;
    let log_start = set_ground_height(
        region,
        origin.relative_n(direction, 2 + random.next_i32_bounded(2)),
    );

    if can_place_entire_fallen_log(region, log_length, log_start, direction) {
        place_fallen_log(region, random, log_length, log_start, direction, config);
    }
    true
}

fn set_ground_height(region: &WorldGenRegion<'_>, pos: BlockPosition) -> BlockPosition {
    let mut pos = pos.above();
    for _ in 0..6 {
        if may_place_on(region, pos) {
            return pos;
        }
        pos = pos.below();
    }
    pos
}

fn may_place_on(region: &WorldGenRegion<'_>, pos: BlockPosition) -> bool {
    tree::valid_tree_pos(region, pos) && is_over_solid_ground(region, pos)
}

fn is_over_solid_ground(region: &WorldGenRegion<'_>, pos: BlockPosition) -> bool {
    region
        .get_block(pos.below())
        .is_side_solid_at(pos, Direction::Up)
}

fn can_place_entire_fallen_log(
    region: &WorldGenRegion<'_>,
    log_length: i32,
    log_start: BlockPosition,
    direction: Direction,
) -> bool {
    let mut pos = log_start;
    let mut gap_in_ground = 0;
    for _ in 0..log_length {
        if !tree::valid_tree_pos(region, pos) {
            return false;
        }
        if is_over_solid_ground(region, pos) {
            gap_in_ground = 0;
        } else {
            gap_in_ground += 1;
            if gap_in_ground > 2 {
                return false;
            }
        }
        pos = pos.relative(direction);
    }
    true
}

fn place_log_block(
    region: &WorldGenRegion<'_>,
    random: &mut RandomSource,
    pos: BlockPosition,
    config: &FallenTreeConfig,
    axis: Option<Direction>,
) {
    let mut state = config.trunk_provider.get_state(region, random, pos);
    if let Some(direction) = axis
        && state.get(Properties::AXIS).is_some()
    {
        state = state.with(Properties::AXIS, direction.axis());
    }
    region.set_block(pos, state);
    mark_above_for_post_processing(region, pos);
}

fn place_stump(
    region: &WorldGenRegion<'_>,
    random: &mut RandomSource,
    origin: BlockPosition,
    config: &FallenTreeConfig,
) {
    place_log_block(region, random, origin, config, None);
    let stump: JavaHashSet = iter::once(origin).collect();
    decorate(region, random, &stump, &config.stump_decorators);
}

fn place_fallen_log(
    region: &WorldGenRegion<'_>,
    random: &mut RandomSource,
    log_length: i32,
    log_start: BlockPosition,
    direction: Direction,
    config: &FallenTreeConfig,
) {
    let mut pos = log_start;
    let mut fallen_log = JavaHashSet::new();
    for _ in 0..log_length {
        place_log_block(region, random, pos, config, Some(direction));
        fallen_log.insert(pos);
        pos = pos.relative(direction);
    }
    decorate(region, random, &fallen_log, &config.log_decorators);
}

fn decorate(
    region: &WorldGenRegion<'_>,
    random: &mut RandomSource,
    logs: &JavaHashSet,
    decorators: &[TreeDecorator],
) {
    if decorators.is_empty() {
        return;
    }
    let empty = JavaHashSet::new();
    let mut decorations = JavaHashSet::new();
    let mut context =
        TreeDecoratorContext::new(region, random, logs, &empty, &empty, &mut decorations);
    for decorator in decorators {
        decorator.place(&mut context);
    }
}