Designing Games with Game Maker - YoYo Games

}
instance_create(xx,yy,ball);
Addressing variables in other instances
As described earlier, you can set variables in the current instance using statements like
x = 3;
But in a number of cases you want to address variables in another instance. For example, you
might want to stop the motion of all balls, or you might want to move the main character to a
particular position, or, in the case of a collision, you might want to set the sprite for the other
instance involved. This can be achieved by preceding the variable name with the name of an
object and a dot. So for example, you can write
ball.speed = 0;
This will change the speed of all instances of object ball. There are a number of special
"objects".
• self: The current instance for which we are executing the action
• other: The other instance involved in a collision event
• all: All instances
• noone: No instance at all (sounds weird probably but it does come in handy as we will
see later on)
• global: Not an instance at all, but a container that stores global variables
So, for example, you can use the following kind of statements:
other.sprite_index = sprite5;
all.speed = 0;
global.message = 'A good result';
global.x = ball.x;