Math Guide

Math
Math is easy in Game Maker, however, you must remember that you have to do something with the result of the math. You either need to display it or store it in a variable.
Arithmetic
Addition
 var = 2 + 2
 var = var + 2
 var += 2
 var += var
 note that gamemaker does not have operations such as ++ or , as possible in C
Subtraction
 var = 2  1
 var = var  2
 var = 2
 var = var
Multiplication
 var = 2 * 2
 var = var * 2
 var *= 2 //not sure if supported
 var *= var //not sure if supported
Division
It is mathematically impossible to divide a number by 0. Be careful when using variables as operands.
 var = 2 / 2
 var = var / 2
 var /= 2 //not sure if supported
 var /= var not sure if supported
Order of Operations
The order of operations can be manipulated using parenthesis.
Percentages
Percentages are decimal fractions.
Trigonometry
 angle  a measurement of rotation around a point.
 point_direction()  calculate the direction between two objects.
 sin()  get the sine
Math Tips
Displaying the Results of Calculation
If you are just playing around with the math capabilities of Game Maker and want to see the results of your calculations as numbers, there are two ways to easy ways to do this. Both of them require you to convert the number to a string using the string() function :
1. Put the result of calculation in the room_caption :
math_result = 4 + 4;
room_caption = string(math_result);
2. Display it using draw_text()
math_result = 4 + 4;
draw_text(10,10,math_result);