Bouncing Ball logics

Question

I have got a ball which bounces of walls. This bounce is simple, i just do this, ( code snippet )

if ( x - moveSpeed < 0 ) // Ball hit left wall
    xVel *= -1;

However i also got a rectangle which the player moves. The bounce on this practically works as the bounce on walls.

But i figured out that when a ball got similar movement as the picture, its impossible for me to make it go straight up again. I therefore need some kind of calculation regarding the rectangles movement to influence the outcoming angle of the ball. The rectangle always got a constant movement speed when moving. This picture shows a rectangle moving to the left and the ball hitting it during its movement, which results in a 90 degree angle. ( Which shouldn't always be 90 ).

Sorry about my crappy pictures i hope they make sense. My math is rusty thats why i really could need a push in the right direction.

Answer 1

Here is a tutorial on some physics (which is what you need to know) and you need to learn about vectors. The tutorial doesn't go over exactly what you are looking for (the reflection of the bounce and angles) but this is a GREAT start for beginning, because you'll need to know all this to finish your project.Game Physics 101

If you want to do it the easy way, here is code in c++ that describes exactly how to do what your looking for.

Edit

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You should actually check out the second link first, its a tutorial on exactly what you need to know. But if you are looking to do more than just make the ball bounce around, say include other moving objects or something like that, check out the first link.

Answer 2

No need for any fancy math here. My understanding of these types of games is that the angle the ball comes off of the paddle is determined by where on the paddle it bounces. If it bounces in the middle, then the current angle is preserved. As it bounces closer to the edge of the paddle, the angle is adjusted in the direction of that side of the paddle. Think of the paddle as a rounded surface.