Blit Scrolling in a Tile-Based World - The Essential Guide to Flash Games - page 459

if (player.turnSpeed > player.maxTurnSpeed) {
player.turnSpeed = player.maxTurnSpeed;
}
}
player.rotation=player.nextRotation;
var carRadians:Number = (player.nextRotation / 360) * (2.0 * Math.PI);
var lookRadians:Number;
player.dx=Math.cos(carRadians)*player.velocity;
player.dy=Math.sin(carRadians)*player.velocity;
player.worldNextX += player.dx;
player.worldNextY += player.dy;
camera.nextX = player.worldNextX - (camera.width * .5);
camera.nextY = player.worldNextY - (camera.height * .5);
if (camera.nextX <0) {
camera.nextX = 0;
player.nextX += player.dx;
}else if (camera.nextX > (worldWidth - camera.width - 1)) {
camera.nextX = (worldWidth - camera.width - 1);
player.nextX += player.dx;
}
if (camera.nextY <0) {
camera.nextY = 0;
player.nextY += player.dy;
}else if (camera.nextY > (worldHeight - (camera.height - 1))) {
camera.nextY = (worldHeight - (camera.height - 1));
player.nextY += player.dy;
}
if (player.velocity < 0) {
player.reverse = true;
lookRadians = ((player.nextRotation-45) / 360) * (2.0 * Math.PI);
lookAheadPoints[0].x=(player.nextX-Math.cos(lookRadians)*player.radius);
lookAheadPoints[0].y = (player.nextY - Math.sin(lookRadians) * player.radius);
//lookradians the same as carRadians for middle
lookAheadPoints[1].x=player.nextX-Math.cos(carRadians)*player.radius;
lookAheadPoints[1].y = player.nextY - Math.sin(carRadians) * player.radius;
lookRadians = ((player.nextRotation+45) / 360) * (2.0 * Math.PI);
lookAheadPoints[2].x = (player.nextX - Math.cos(lookRadians) * player.radius);
lookAheadPoints[2].y = (player.nextY - Math.sin(lookRadians) * player.radius);
}else {
player.reverse = false;
lookRadians = ((player.nextRotation-45) / 360) * (2.0 * Math.PI);
lookAheadPoints[0].x=(player.nextX+Math.cos(lookRadians)*player.radius);
lookAheadPoints[0].y = (player.nextY + Math.sin(lookRadians) * player.radius);