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#![allow(missing_docs)]
#![allow(dead_code)]
use std::vec::Vec;
#[allow(missing_debug_implementations)]
#[derive(Clone, Copy)]
pub enum TtfType {
Raw(&'static [u8]),
TrueTypeMagic,
OpenTypeMagic,
FontCollectionMagic,
Int8(i8),
UInt8(u8),
Int16(i16),
UInt16(u16),
Int32(i32),
UInt32(u32),
CFFInt(i32),
}
pub fn convert(values: &[TtfType]) -> Vec<u8> {
let mut data = Vec::with_capacity(256);
for v in values {
convert_type(*v, &mut data);
}
data
}
pub fn convert_type(value: TtfType, data: &mut Vec<u8>) {
match value {
TtfType::Raw(bytes) => {
data.extend_from_slice(bytes);
}
TtfType::TrueTypeMagic => {
data.extend_from_slice(&[0x00, 0x01, 0x00, 0x00]);
}
TtfType::OpenTypeMagic => {
data.extend_from_slice(&[0x4F, 0x54, 0x54, 0x4F]);
}
TtfType::FontCollectionMagic => {
data.extend_from_slice(&[0x74, 0x74, 0x63, 0x66]);
}
TtfType::Int8(n) => {
data.extend_from_slice(&i8::to_be_bytes(n));
}
TtfType::UInt8(n) => {
data.extend_from_slice(&u8::to_be_bytes(n));
}
TtfType::Int16(n) => {
data.extend_from_slice(&i16::to_be_bytes(n));
}
TtfType::UInt16(n) => {
data.extend_from_slice(&u16::to_be_bytes(n));
}
TtfType::Int32(n) => {
data.extend_from_slice(&i32::to_be_bytes(n));
}
TtfType::UInt32(n) => {
data.extend_from_slice(&u32::to_be_bytes(n));
}
TtfType::CFFInt(n) => {
match n {
-107..=107 => {
data.push((n as i16 + 139) as u8);
}
108..=1131 => {
let n = n - 108;
data.push(((n >> 8) + 247) as u8);
data.push((n & 0xFF) as u8);
}
-1131..=-108 => {
let n = -n - 108;
data.push(((n >> 8) + 251) as u8);
data.push((n & 0xFF) as u8);
}
-32768..=32767 => {
data.push(28);
data.extend_from_slice(&i16::to_be_bytes(n as i16));
}
_ => {
data.push(29);
data.extend_from_slice(&i32::to_be_bytes(n));
}
}
}
}
}
#[derive(Debug)]
pub struct Writer {
pub data: Vec<u8>,
}
impl Writer {
pub fn new() -> Self {
Writer { data: Vec::with_capacity(256) }
}
pub fn offset(&self) -> usize {
self.data.len()
}
pub fn write(&mut self, value: TtfType) {
convert_type(value, &mut self.data);
}
}