如何使玩家撞到障碍物然后离开（Java）

Question

here is my code for when my player intersects a GRect, but it only works for 2 sides of the rect. The other 2 give an undesirable effect.

private void gameLoop() {
    boolean done = false;
    while (!done) {

        if (pan.getBounds().intersects(b.getBounds())) {

            pan.move(-10, -10);
        }

How can i make my player "see" the rect as an obstacle and collide with it? I am using key listeners to move the player.

EDIT

i added the following if statements to check for interactions of the player with each side of the obstacle, but it again seems to work for left and bottom sides. I need all four sides .

I am using pan.move because it is what i use to move the player in the first place, when a key is pressed. So for example when i click left, i use pan.move(-10,0) and so to prevent the player from moving left i use pan.move(10,0)

    if (pan.getBounds().intersects(b1.getBounds())) {


        if ((pan.getX() +PAN_WIDTH ) > b1.getX()) {  // left
            pan.move(-10, 0);

        }
        if ((pan.getY() PAN_WIDTH ) > b1.getY()) {  //top
            pan.move(0, -10);

        }
        if ((pan.getY()) < b1.getY() + OBSTACLE_WIDTH) { // bottom
            pan.move(0, 10);

        }
        if ((pan.getX() PAN_WIDTH) < b1.getX() + OBSTACLE_HEIGHT) {  // right
            pan.move(10, 0);

        }
        }

Answer 1

There are lots of problem with your code, here is some corrections. You're messing up with width and height But without knowing all of your code, I don't guarantee that your way of doing it is okay.

if (pan.getBounds().intersects(b1.getBounds())) {

    if ((pan.getX() + pan.getWidth()) > b1.getX()) {  // left
        pan.move(-10, 0);
    } else if (pan.getX() < (b1.getX() + b1.getWidth())) { // right
        pan.move(10,0);
    }

    if ((pan.getY() + pan.getHeight()) > b1.getY()) {  //top
        pan.move(0, -10);
    } else if (pan.getY() < (b1.getY() + b1.getHeight())) { // bottom
        pan.move(0, 10);
    }
}

Also, I suggest you to change your constant to methods like getWidth() . In the case you change the dimensions of your obstacle or player, you'll not have to change the constants too.

Also, moving your player is not a good way of doing it. Your player should have two fields representing the moves you'll perform. Then in the case of collision, you just have to put these fields to 0. You don't want your player to move when collision, you just want it to stop going more left/right/up/down.

For example if you change the speed of your player, then you'll have to change all of these pan() manually. That's going to get you problems if you don't realize that.