rgc-chart 0.0.3

A library for parsing and writing rhythm game charts.
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

use crate::models;
use crate::models::common::{
    KeyType,
    TimingChangeType,
};
use crate::utils::string::add_key_value_template;
use crate::utils::time::find_sliderend_time;
#[allow(unused)]
use crate::errors;

#[inline(always)]
fn bpm_to_beatlength(bpm: &f32) -> f32 {
    60000.0 / bpm
}

#[inline(always)]
fn multiplier_to_beatlength(multiplier: &f32) -> f32 {
    if *multiplier == 0.0 { return -10000.0 }
    -100.0 / multiplier.abs()
}

#[inline(always)]
fn column_to_coords(column: usize, key_count: usize) -> u16 {
    (column as f32 * 512.0 / key_count as f32) as u16
}

pub(crate) fn to_osu(chart: &models::chart::Chart) -> Result<String, Box<dyn std::error::Error>> {
    let mut template = String::from("osu file format v14\n");
    let key_count = chart.chartinfo.key_count;

    // General
    template.push_str("\n[General]\n");
    add_key_value_template(&mut template,
        "AudioFilename", ": ", &chart.chartinfo.song_path, "\n");
    add_key_value_template(&mut template,
        "AudioLeadIn", ": ", "0", "\n");
    add_key_value_template(&mut template,
        "PreviewTime", ": ", &chart.chartinfo.preview_time.to_string(), "\n");
    template.push_str("Countdown: 0
SampleSet: Soft
StackLeniency: 0.7
Mode: 3
LetterboxInBreaks: 0
SpecialStyle: 0
WidescreenStoryboard: 1");
    template.push('\n');

    // Editor
    template.push_str("\n[Editor]
DistanceSpacing: 1
BeatDivisor: 4
GridSize: 4
TimelineZoom: 1
");

    // Metadata
    template.push_str("\n[Metadata]\n");
    add_key_value_template(&mut template,
        "Title", ": ", &chart.metadata.title.replace("\n", ""), "\n");
    add_key_value_template(&mut template,
        "TitleUnicode", ": ", &chart.metadata.alt_title, "\n");
    add_key_value_template(&mut template,
        "Artist", ": ", &chart.metadata.artist, "\n");
    add_key_value_template(&mut template,
        "ArtistUnicode", ": ", &chart.metadata.alt_artist, "\n");
    add_key_value_template(&mut template,
        "Creator", ": ", &chart.metadata.creator, "\n");
    add_key_value_template(&mut template,
        "Version", ": ", &chart.chartinfo.difficulty_name, "\n");
    add_key_value_template(&mut template,
        "Source", ": ", &chart.metadata.source, "\n");
    add_key_value_template(&mut template,
        "Tags", ": ", &chart.metadata.tags.join(" "), "\n");
    add_key_value_template(&mut template,
        "BeatmapID", ": ", "0", "\n");
    add_key_value_template(&mut template,
        "BeatmapSetID", ": ", "-1", "\n");

    // Difficulty
    template.push_str("\n[Difficulty]\n");
    add_key_value_template(&mut template,
        "HPDrainRate", ": ", "8.5", "\n");
    add_key_value_template(&mut template,
        "CircleSize", ": ", &key_count.to_string(), "\n");
    template.push_str("OverallDifficulty:8
ApproachRate:5
SliderMultiplier:1.4
SliderTickRate:1");
    template.push('\n');

    // Events
    template.push_str("\n[Events]\n");
    template.push_str("//Background and Video events\n");
    template.push_str(&format!("0,0,\"{}\",0,0\n", &chart.chartinfo.bg_path));
    template.push_str("//Break Periods
//Storyboard Layer 0 (Background)
//Storyboard Layer 1 (Fail)
//Storyboard Layer 2 (Pass)
//Storyboard Layer 3 (Foreground)
//Storyboard Layer 4 (Overlay)
//Storyboard Sound Samples\n");

    // process timing points
    template.push_str("\n[TimingPoints]\n");
    for timing_point in chart.timing_points.iter_views() {
        match timing_point.change_type {
            TimingChangeType::Bpm => {
                template.push_str(&format!("{},{},4,1,0,100,1,0\n",
                    timing_point.time,
                    bpm_to_beatlength(timing_point.value),
                ));
            },
            TimingChangeType::Sv => {
                template.push_str(&format!("{},{},4,1,0,100,0,0\n",
                    timing_point.time,
                    multiplier_to_beatlength(timing_point.value),
                ));
            },
            _ => {}
        }
    }

    template.push_str("\n[HitObjects]\n");
    let hitobjects: Vec<(&f32, &f32, &Vec<u8>, &Vec<KeyType>)> = chart.hitobjects.iter_zipped().collect();
    template.reserve(hitobjects.len() * key_count as usize);
    #[allow(unused)]
    for (row_idx, (time, beat, hitsounds, row)) in hitobjects.iter().enumerate() {
        for (i, key_type) in row.iter().enumerate() {
            let coords = column_to_coords(i, chart.chartinfo.key_count as usize);
            match key_type {
                KeyType::Normal => {
                    template.push_str(&format!("{},192,{},1,0,0:0:0:0:\n", coords, **time as i32));
                },
                KeyType::SliderStart => {
                    let slider_end_time = find_sliderend_time(row_idx, i, &hitobjects);
                    template.push_str(&format!("{},192,{},128,0,{}:0:0:0:0:\n", coords, **time as i32, slider_end_time as i32));
                },
                _ => continue,
            }
        }
    }

    Ok(template)
}