Tips & Reminders I've Picked Up For Working With GameMaker Studio & GML

GameMaker Tips.txt

#GameMaker Tips

###Tip 1
Do Not Use WHILE loops in the GUI, Step or other events that loop every second.  
It's a good way to fry your memory and crash GameMaker's Runner.

###Tip 2
If you intend to use an IF statement to check for key input do not use -keyboard_checks. For example

    **var left_key = -keyboard_check(vk_left);**
    var right_key = keyboard_check(vk_right);
    **var a_key = -keyboard_check(ord("A"));**
    var d_key = keyboard_check(ord("D"));

    **if (left_key || right_key) {
      move = right_key - left_key;
    }
    else if (a_key || d_key) {
      move = d_key - a_key;
    }**

This will fail to run as soon as it hits the if statement since it will never result in 1 when you press "A" or "Left".  
The "D" key and "Right" arrow work perfectly fine as they return 1 when pressed and 0 when not pressed.