与墙碰撞时如何计算球的坐标？

Question

I'm developing a game like bubble shooter and need to implement bounce of ball off the vertical wall. I have the following inputs:

1. Starting position of bubble: {left: 382, right: 378}
2. Firing angle in radians: 1.34
3. Game board sizes: {width: 760, height: 620} .
4. Sizes of the bubble are {width: 44px, height: 44px}

I have two walls to the left side of the bubble and to the right side of the bubble.

How could I calculate bubble's center point coordinates to stop it on collided left of right wall?

Answer 1

If the dimensions for the bubble are 44x44, I assume it means that the bounding box is that size (because you don't measure circles with width and height).

If that's the case, than you have something like

That means that the diameter of the circle is 44px, which means the radius of the circle is 22px. The distance from the wall to the center of the circle, assuming the wall is tangent to the circle, would be 1r or 22px.

If you're counting from the top left of the bounding box, you want to add 22px to both the x and the y coordinate, and that would give you the coordinates of the center.