Keyboard Input

GameMaker: Studio has a number of constants and functions related to the keyboard and how it can be used to make things happen in your games.

When dealing with the keyboard in GameMaker: Studio you have a variety of functions that can be used to recognise different keyboard states like pressed or released. There are also some that store all the keypresses as a string or that can tell you what the last key pressed was, as well as others that allow you to clear the keyboard state completely.

NOTE: These functions are designed for Windows/Mac/Ubuntu desktop platforms only. You may find some of the in-built variables and constants aren't valid on other platforms and many of the functions won't work on mobiles.

Now, each key is normally defined by a number, called the ascii code, and you can directly input this number into these functions and they will work fine... But, as it's a bit difficult to remember so many numbers and the relationship that they have with your keyboard, GameMaker: Studio has a series of constants for the most used keyboard special keys and a special function ord() to return the number from ordinary typed characters (either letters or numbers).

The following is a small example of how to use ord():

if keyboard_check(ord('A'))
   hspeed = -5;

So, the above will check the "A" key and if it's being pressed then it'll set the horizontal speed of the object to -5. Note, that the "A" is a capital "A", and that when using ord() the keyboard key to check must always be written in quotes and as a capital. Now, what if you want to use the arrow keys? Or if you want to modify an action using the "shift" key? Well, for that GameMaker: Studio has a series of vk_ constants (vk_ stands for virtual keyboard) that you can use in place of ord or the ascii code.

Here is a complete list of the vk_ constants:

Constant Description
vk_nokey keycode representing that no key is pressed
vk_anykey keycode representing that any key is pressed
vk_left keycode for left arrow key
vk_right keycode for right arrow key
vk_up keycode for up arrow key
vk_down keycode for down arrow key
vk_enter enter key
vk_escape escape key
vk_space space key
vk_shift either of the shift keys
vk_control either of the control keys
vk_alt alt key
vk_backspace backspace key
vk_tab tab key
vk_home home key
vk_end end key
vk_delete delete key
vk_insert insert key
vk_pageup pageup key
vk_pagedown pagedown key
vk_pause pause/break key
vk_printscreen printscreen/sysrq key
vk_f1 ... vk_f12 keycode for the function keys F1 to F12
vk_numpad0 ... vk_numpad9 number keys on the numeric keypad
vk_multiply multiply key on the numeric keypad
vk_divide divide key on the numeric keypad
vk_add key on the numeric keypad
vk_subtract subtract key on the numeric keypad
vk_decimal decimal dot keys on the numeric keypad

The following constants can only be used with keyboard_check_direct():

Constant Description
vk_lshift left shift key
vk_lcontrol left control key
vk_lalt left alt key
vk_rshift right shift key
vk_rcontrol right control key
vk_ralt right alt key

The following is a small example of how to use the vk_ constants:

if keyboard_check_pressed(vk_tab)

The above code will detect if the "Tab" key is pressed and create an instance of object "obj_Menu" if it is.

For information on the available GameMaker: Studio keyboard functions, please see the following sections of the manual:

  1. io_clear
  2. keyboard_check
  3. keyboard_check_pressed
  4. keyboard_check_released
  5. keyboard_check_direct
  6. keyboard_clear
  7. keyboard_key_press
  8. keyboard_key_release
  9. keyboard_key
  10. keyboard_lastkey
  11. keyboard_lastchar
  12. keyboard_string
  13. keyboard_set_map
  14. keyboard_get_map
  15. keyboard_unset_map
  16. keyboard_get_numlock
  17. keyboard_set_numlock

Back: Mouse, Keyboard and Other Controls
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