I am making a 2D tile map based putt-putt game.

I have collision detection working between the ball and the walls of the map, although when the ball collides at the meeting point between 2 tiles I offset it by 0.5 so that it doesn't get stuck in the wall. This aint a huge issue though.

  if(y % 20 == 0) {
    y+=0.5;
  }

  if(x % 20 == 0) {
    x+=0.5;
  }

Collisions work as follows

1. Find the closest point between each tile and the center of the ball
2. If distance(ball_x, ball_y, close_x, close_y) <= ball_radius and the closest point belongs to a solid object, collision has occured
3. Invert X/Y speed according to side of object collided with

The next thing I tried to do was implement floating blocks in the middle of the map for the ball to bounce off of. When a ball collides with a corner of the block, it gets stuck in it. So I changed my determineRebound() function to treat corners as if they were circles. Here's that functon:

   `i and j are indexes of the solid object in the 2d map array. x & y are centre point of ball.`
   void determineRebound(int _i, int _j) {
     if(y > _i*tile_w && y < _i*tile_w + tile_w) {
        //Not a corner
        xs*=-1;
      } else if(x > _j*tile_w && x < _j*tile_w + tile_w) {
        //Not a corner
        ys*=-1;
      } else {
        //Corner       
        float nx = x - close_x;
        float ny = y - close_y;
        float len = sqrt(nx * nx + ny * ny);
        nx /= len;
        ny /= len;

        float projection = xs * nx + ys * ny;
        xs -= 2 * projection * nx;
        ys -= 2 * projection * ny;
      }
    }

This is where things have gotten messy. Collisions with 'floating' corners work fine, but now when the ball collides near the meeting point of 2 tiles, it detects a corner collision and does not rebound as expected.

I'm a bit in over my head at this point. I guess I'm wondering if I'm going about making this sort of game in the right way. Is a 2d tile map the way to go? If so, is there a problem with my collision logic and where am I going wrong?

Any advice/feedback would be great.