|key||The key to check the down state of.|
With this function you can check to see if a key is held down or
not. Unlike the keyboard_check_pressed
functions which are only triggered once when the key is pressed or
released, this function is triggered every step that the key is
held down for.
x -= 5;
The above code will check to see if the arrow key is being pressed and move the instance 5 pixels left every step that it returns true.