Function blockish::render_thread_pool

pub fn render_thread_pool(
    width: u32,
    height: u32,
    coordinate_to_rgba: &(dyn Fn(u32, u32) -> (u8, u8, u8, u8) + Sync + Send),
    write_eol: bool,
    pool: &mut Pool,
    output_buffers: &mut Vec<Vec<u8>>
)