move: implement follow the leader algorithm

snake.ts

@@ -1,5 +1,5 @@
 import Vec2d from "./vec.js";
-import { fillCircle, lerp, lerpRgb } from "./common.js";
+import { resizeCanvas, fillCircle, lerp, lerpRgb } from "./common.js";
 
 // constants
 const SNAKE_RADIUS = 10;
@@ -27,12 +27,6 @@ let speed = 200; // px/s
 let interpolation_factor = 10;
 let paused = false;
 
-function resizeCanvas(ctx: CanvasRenderingContext2D) {
-  ctx.canvas.width = ctx.canvas.clientWidth;
-  ctx.canvas.height = ctx.canvas.clientHeight;
-  ctx.clearRect(0, 0, ctx.canvas.width, ctx.canvas.height);
-}
-
 let lastTime: number | undefined = undefined;
 
 function drawSnake(ctx: CanvasRenderingContext2D, bounds: Vec2d) {