# How do I make a sprite speed up as a variable increases?

I have a game where the player eats food. If they eat the apple or the strawberry they get a point, and the location of the apple and strawberry changes when they eat two of them. The player needs to dodge the doughnut while doing this.

I want the doughnut to move faster once the player has eaten a certain amount of apples and strawberries, but my game keeps glitching out an pushing the doughnut into the corner when it speeds up.

Any suggestions?

In your example youâ€™re setting the velocity to vx=100 and vy=100 every frame which means itâ€™ll always be going towards the bottom right.

If you want it to speed up, you need to take the angle of the velocity into account. You can do this with a little trig:

In this example, the atan2 gives us the angle of the velocity in radians. Then you multiply the x speed by the cos and the y speed by the sin.

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Alternatively, you can avoid the trig by moving your speed up code into the overlap event. That way it will only run once each overlap instead of once every frame:

Every time it runs the angle of velocity will be reset to 45 degrees however, since the vx and vy are always the same.

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Thanks! I really appreciate the help!