diff options
| -rw-r--r-- | src/main.rs | 47 |
1 files changed, 18 insertions, 29 deletions
diff --git a/src/main.rs b/src/main.rs index ffa6320..0d73c83 100644 --- a/src/main.rs +++ b/src/main.rs @@ -4,26 +4,8 @@ use std::io::{stderr, stdout, Read, Write}; use std::sync::mpsc::{Receiver, SyncSender, TryRecvError}; use std::time::{Duration, SystemTime}; -#[derive(Debug)] -struct Gen { - state: u64, -} - -impl Gen { - fn new() -> Gen { - Gen { - state: SystemTime::now() - .duration_since(SystemTime::UNIX_EPOCH) - .unwrap() - .as_nanos() as u64, - } - } - - fn rand(&mut self, max: i32) -> i32 { - // https://en.wikipedia.org/wiki/Linear_congruential_generator - self.state = self.state.wrapping_mul(6364136223846793005).wrapping_add(1); - (self.state >> 33 & 0x7fffffff) as i32 % max - } +fn rand(max: i32) -> i32 { + unsafe { libc::rand() % max } } #[derive(Debug, Clone, Copy, PartialEq, Eq)] @@ -195,11 +177,11 @@ impl Snake { Ok(()) } - fn print(&self, g: &mut Gen) -> Result<(), Box<dyn Error>> { + fn print(&self) -> Result<(), Box<dyn Error>> { let next = self.next(); if (self.direction == Dir::Left || self.direction == Dir::Right) && in_bounds(next) - && g.rand(40) == 0 + && rand(40) == 0 { move_cursor(next)?; write!(stdout(), "~")?; @@ -275,22 +257,21 @@ impl Fruit { Ok(()) } - fn new_pos(&mut self, g: &mut Gen) { - self.pos.row = g.rand(i32::from(Screen::ROWS) - 4) as u16 + 2; - self.pos.col = g.rand(i32::from(Screen::COLS) - 4) as u16 + 2; + fn new_pos(&mut self) { + self.pos.row = rand(i32::from(Screen::ROWS) - 4) as u16 + 2; + self.pos.col = rand(i32::from(Screen::COLS) - 4) as u16 + 2; } } fn snake() -> Result<i64, Box<dyn Error>> { let screen = Screen::init()?; - let mut g = Gen::new(); let mut snake = Snake { body: vec![pos(Screen::ROWS / 2, Screen::COLS / 2)], direction: Dir::Right, growing: 0, }; let mut fruit = Fruit { pos: pos(0, 0) }; - fruit.new_pos(&mut g); + fruit.new_pos(); let mut score: i64 = 0; let mut real_score: i64 = 0; let mut delay = Duration::from_millis(200); @@ -298,7 +279,7 @@ fn snake() -> Result<i64, Box<dyn Error>> { loop { move_cursor(pos(0, 3))?; write!(stdout(), " Score: {} ", score)?; - snake.print(&mut g)?; + snake.print()?; fruit.print()?; move_cursor(pos(Screen::ROWS - 1, Screen::COLS - 1))?; @@ -316,7 +297,7 @@ fn snake() -> Result<i64, Box<dyn Error>> { if snake.body[0] == fruit.pos { snake.growing += 6; loop { - fruit.new_pos(&mut g); + fruit.new_pos(); if !snake.body.contains(&fruit.pos) { break; } @@ -333,6 +314,14 @@ fn snake() -> Result<i64, Box<dyn Error>> { } fn main() { + unsafe { + libc::srand( + SystemTime::now() + .duration_since(SystemTime::UNIX_EPOCH) + .unwrap() + .as_nanos() as u32, + ); + } let score = match snake() { Ok(s) => s, Err(err) => { |