矩形和圆形解决碰撞

Question

How can I change the dy of the ball if it touches the top and bottom of the block? Now it just gets a wobble effect and gets trapped inside of the block when it hits the top or bottom. Here is my Jsfiddle: https://jsfiddle.net/6qh70wdo/

if (ball.x - ball.radius < block.x + block.w &&
    ball.x + ball.radius > block.x &&
    ball.y - ball.radius < block.y + block.h &&
    ball.y + ball.radius > block.y) {
    ball.dx  = -ball.dx;
}

Answer 1

I would break it up into two sections. First detect if it is being hit and then worry about where it's hitting. I think you could do something like this:

var bool = ball.x - ball.radius < block.x + block.w &&
    ball.x + ball.radius > block.x &&
    ball.y - ball.radius < block.y + block.h &&
    ball.y + ball.radius > block.y) {
    ball.dx  = -ball.dx;

if(bool) // if true, meaning a hit, find which direction.
    if(ball.x - ball.radius < block.x + block.w || ball.x + ball.radius > block.x){
        ball.dx = -ball.dx; //hit detected on left/right...change left/right direction
    }else{
        ball.dy = -ball.dy; //hit detected on top/bottom...change top/bottom direction
    }
}