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

use std::io::Read;

use crate::error::Result;
use crate::reader::decode::rle_v2::RleReaderV2;
use crate::reader::decode::util::{read_ints, read_u8, rle_v2_delta_bit_width, zigzag_decode};

impl<R: Read> RleReaderV2<R> {
    pub fn read_direct_values(&mut self, header: u8) -> Result<()> {
        let fbo = (header >> 1) & 0x1F;
        let fb = rle_v2_delta_bit_width(fbo);

        // 9 bits for length (L) (1 to 512 values)
        let second_byte = read_u8(&mut self.reader)?;

        let mut length = ((header as u64 & 0x01) << 8) as usize | second_byte as usize;
        // runs are one off
        length += 1;

        // write the unpacked values and zigzag decode to result buffer
        read_ints(
            &mut self.literals,
            self.num_literals,
            length,
            fb as usize,
            &mut self.reader,
        )?;

        if self.signed {
            for _ in 0..length {
                self.literals[self.num_literals] =
                    zigzag_decode((self.literals[self.num_literals]) as u64);
                self.num_literals += 1;
            }
        } else {
            self.num_literals += length;
        }

        Ok(())
    }
}