Pan camera within bounds of large image

I have a camera that I pan around a large image which works fine, however when I reach the end of the image I can keep panning on and on, forver. I have looked everywhere for an answer on how to prevent this but the only one I found did not use panning and I could not get it to work.

My code atm is very simple:

map.setPosition(-map.getWidth()/2, -map.getHeight()/2); public boolean pan(float x, float y, float deltaX, float deltaY) { cam.translate(-deltaX * PAN_SPEED, deltaY * PAN_SPEED); cam.update(); return true; } 

My Image is very large, 4096x4096, and my camera is 480x800. My problem is I have no idea how to get the distance I have panned, and even if I did I dont know how to stop a pan from moving past a certain point, just setting camera position won't work because then there will be a "bounce" back.

Basically I have a rectangle inside another rectangle, and the inner rectangle should not be allowed to move outside the larger. But as I said I don't really know where to start since I can't get the panning distance.

Ex of something I've tried:

@Override public boolean touchDown(float x, float y, int pointer, int button) { startX = x * PAN_SPEED; return false; } @Override public boolean pan(float x, float y, float deltaX, float deltaY) { if(-totalX > map.getX() + cam.viewportWidth/2){ cam.translate(-deltaX * PAN_SPEED, deltaY * PAN_SPEED); cam.update(); } return true; } @Override public boolean panStop(float x, float y, int pointer, int button) { endX = x* PAN_SPEED; totalX += endX - startX; System.out.println("pan: " + totalX + ", map: " + map.getX()); return true; } 

This is just a test, basically I can't move anymore after I hit the left border of the image, but totalX still keeps adding up so this will not work.

EDIT: Got it to work, code below:

@Override

public boolean pan(float x, float y, float deltaX, float deltaY) { cam.translate(-deltaX, deltaY); keepCameraInBounds(); cam.update(); return true; } private void keepCameraInBounds () { OrthographicCamera c = this.cam; Vector3 camPos = c.position; float HW = c.viewportWidth / 2, HH = c.viewportHeight / 2; camPos.x = MathUtils.clamp(camPos.x, map.getWidth()/2 - map.getWidth() + HW, map.getWidth() - map.getWidth()/2 - HW); camPos.y = MathUtils.clamp(camPos.y, map.getHeight()/2 - map.getWidth() + HH, map.getHeight() - map.getHeight()/2 - HH); }