tile_animation.rs

use crate::tilemap::Tilemap;
use std::time::Duration;
use tetra::graphics::{Rectangle, Texture, DrawParams};
use tetra::{Context, time, graphics};

pub struct TileAnimation{
	frames: Vec<Rectangle>,
	frame_length: Duration,
	tile_durations: Vec<Duration>,
	current_frame: usize,
	timer: Duration,
	repeating: bool,
}

impl TileAnimation {
	pub fn new(tilemap: &Tilemap, tile_ids: &[u32], mut tile_durations: Vec<Duration>) -> Self{
		if tile_ids.len() != tile_durations.len(){
			let duration = tile_durations[0];
			for _i in tile_durations.len()..tile_ids.len(){
				tile_durations.push(duration);
			}
		}
		TileAnimation{
			frames: tilemap.get_frames_from_ids(tile_ids),
			frame_length: tile_durations[0],
			tile_durations,
			current_frame: 0,
			timer: Duration::from_secs(0),
			repeating: true,
		}
	}

	pub fn once(tilemap: &Tilemap, tile_ids: &[u32],tile_durations: Vec<Duration>) -> Self{
		TileAnimation{
			frames: tilemap.get_frames_from_ids(tile_ids),
			frame_length: tile_durations[0],
			tile_durations,
			current_frame: 0,
			timer: Duration::from_secs(0),
			repeating: false,
		}
	}

	pub fn advance(&mut self, ctx: &Context) {
		self.advance_by(time::get_delta_time(ctx));
	}

	pub fn advance_by(&mut self, duration: Duration) {
		self.timer += duration;

		let frames_remaining = self.current_frame < self.frames.len() - 1;
		if frames_remaining || self.repeating {
			while self.timer >= self.frame_length {
				self.current_frame = (self.current_frame + 1) % self.frames.len();
				self.timer -= self.frame_length;
				self.frame_length = self.tile_durations[self.current_frame];
			}
		} else if self.timer > self.frame_length {
			self.timer = self.frame_length;
		}
	}

	pub fn restart(&mut self) {
		self.current_frame = 0;
		self.timer = Duration::from_secs(0);
	}

	pub fn draw<P>(&mut self, ctx: &mut Context, texture: &Texture, params: P)
		where
			P: Into<DrawParams>,
	{
		let mut params = params.into();
		params.clip = Some(self.frames[self.current_frame]);
		graphics::draw(ctx, texture, params)
	}
}