moving a sprite causes jerky movement
- by mac_55
I've got some jerky movement of my sprite.
Basically, when the user touches a point on the screen, the sprite should move to that point. This is working mostly fine... it's even taking into account a delta - because frame rate may not be consistant.
However, I notice that the y movement usually finishes before the x movement (even when the distances to travel are the same), so it appears like the sprite is moving in an 'L' shape rather than a smooth diagonal line.
Vertical and horizontal velocity (vx, vy) are both set to 300. Any ideas what's wrong? How can I go about getting my sprite to move in a smooth diagonal line?
- (void)update:(ccTime)dt
{
int x = self.position.x;
int y = self.position.y;
//if ball is to the left of target point
if (x<targetx)
{
//if movement of the ball won't take it to it's target position
if (x+(vx *dt) < targetx)
{
x += vx * dt;
}
else {
x = targetx;
}
} else if (x>targetx) //same with x being too far to the right
{
if (x-(vx *dt) > targetx)
{
x -= vx * dt;
}
else {
x = targetx;
}
}
if (y<targety)
{
if (y+(vy*dt)<targety)
{
y += vy * dt;
}
else {
y = targety;
}
} else if (y>targety)
{
if (y-(vy*dt)>targety)
{
y -= vy * dt;
}
else {
y = targety;
}
}
self.position = ccp(x,y);
}
