boolean change = false;
        if (Gdx.input.isKeyPressed(Input.Keys.A)) {
            cam.zoom += 0.02;
            change = true;
        }
        if (Gdx.input.isKeyPressed(Input.Keys.Q)) {
            cam.zoom -= 0.02;
            change = true;
        }
        if (Gdx.input.isKeyPressed(Input.Keys.LEFT)) {
            cam.translate(-3, 0, 0);
            change = true;
        }
        if (Gdx.input.isKeyPressed(Input.Keys.RIGHT)) {
            cam.translate(3, 0, 0);
            change = true;
        }
        if (Gdx.input.isKeyPressed(Input.Keys.DOWN)) {
            cam.translate(0, -3, 0);
            change = true;
        }
        if (Gdx.input.isKeyPressed(Input.Keys.UP)) {
            cam.translate(0, 3, 0);
            change = true;
        }
        if (Gdx.input.isKeyPressed(Input.Keys.W)) {
            cam.rotate(-rotationSpeed, 0, 0, 1);
            change = true;
        }
        if (Gdx.input.isKeyPressed(Input.Keys.E)) {
            cam.rotate(rotationSpeed, 0, 0, 1);
            change = true;
        }

        if(change) {
            cam.zoom = MathUtils.clamp(cam.zoom, 0.1f, 100 / cam.viewportWidth);

            float effectiveViewportWidth = cam.viewportWidth * cam.zoom;
            float effectiveViewportHeight = cam.viewportHeight * cam.zoom;

            cam.position.x = MathUtils.clamp(cam.position.x, effectiveViewportWidth / 2f, 100 - effectiveViewportWidth / 2f);
            cam.position.y = MathUtils.clamp(cam.position.y, effectiveViewportHeight / 2f, 100 - effectiveViewportHeight / 2f);
        }