doukutsu-rs/src/bmfont.rs

95 lines
2.9 KiB
Rust

use std::collections::HashMap;
use std::io;
use byteorder::{ReadBytesExt, LE};
use crate::framework::error::GameError::ResourceLoadError;
use crate::framework::error::GameResult;
#[derive(Debug)]
pub struct BmChar {
pub x: u16,
pub y: u16,
pub width: u16,
pub height: u16,
pub xoffset: i16,
pub yoffset: i16,
pub xadvance: i16,
pub page: u8,
pub chnl: u8,
}
#[derive(Debug)]
pub struct BMFont {
pub pages: u16,
pub font_size: i16,
pub line_height: u16,
pub base: u16,
pub chars: HashMap<char, BmChar>,
}
const MAGIC: [u8; 4] = [b'B', b'M', b'F', 3];
impl BMFont {
pub fn load_from<R: io::Read + io::Seek>(mut data: R) -> GameResult<Self> {
let mut magic = [0u8; 4];
let mut pages = 0u16;
let mut chars = HashMap::with_capacity(128);
let mut font_size = 0i16;
let mut line_height = 0u16;
let mut base = 0u16;
data.read_exact(&mut magic)?;
if magic != MAGIC {
return Err(ResourceLoadError("Invalid magic".to_owned()));
}
while let Ok(block_type) = data.read_u8() {
let length = data.read_u32::<LE>()?;
match block_type {
1 => {
font_size = data.read_i16::<LE>()?;
data.seek(io::SeekFrom::Current(length as i64 - 2))?;
}
2 => {
line_height = data.read_u16::<LE>()?;
base = data.read_u16::<LE>()?;
data.seek(io::SeekFrom::Current(4))?;
pages = data.read_u16::<LE>()?;
data.seek(io::SeekFrom::Current(length as i64 - 10))?;
}
3 | 5 => {
data.seek(io::SeekFrom::Current(length as i64))?;
}
4 => {
let count = length / 20;
for _ in 0..count {
let id = data.read_u32::<LE>()?;
let x = data.read_u16::<LE>()?;
let y = data.read_u16::<LE>()?;
let width = data.read_u16::<LE>()?;
let height = data.read_u16::<LE>()?;
let xoffset = data.read_i16::<LE>()?;
let yoffset = data.read_i16::<LE>()?;
let xadvance = data.read_i16::<LE>()?;
let page = data.read_u8()?;
let chnl = data.read_u8()?;
if let Some(chr) = std::char::from_u32(id) {
chars.insert(chr, BmChar { x, y, width, height, xoffset, yoffset, xadvance, page, chnl });
}
}
}
_ => {
return Err(ResourceLoadError("Unknown block type.".to_owned()));
}
}
}
Ok(Self { pages, font_size, line_height, base, chars })
}
}