Designing Games with Game Maker - YoYo Games

image_index When the image has multiple subimages the program cycles
through them. This variable indicates the currently drawn subimage (they are
numbered starting from 0). You can change the current image by changing
this variable. The program will continue cycling, starting at this new index.
(The value can have a fractional part. In this case it is always rounded down to
obtain the subimage that is drawn.)
image_speed The speed with which we cycle through the subimages. A value
of 1 indicates that each step we get the next image. Smaller values will switch
subimages slower, drawing each subimage multiple times. Larger values will
skip subimages to make the motion faster. Sometimes you want a particular
subimage to be visible and don't want the program to cycle through all of
them. This can be achieved by setting the speed to 0 and choosing the correct
subimage. For example, assume you have an object that can rotate and you
create a sprite that has subimages for a number of orientations (counter-
clockwise). Then, in the step event of the object you can set
{
image_index = direction * image_number/360;
image_speed = 0;
}
depth Normally images are drawn in the order in which the instances are
created. You can change this by setting the image depth. The default value is
0, unless you set it to a different value in the object properties. The higher the
value the further the instance is away. (You can also use negative values.)
Instances with higher depth will lie behind instances with a lower depth.
Setting the depth will guarantee that the instances are drawn in the order you
want (e.g. the plane in front of the cloud). Background instances should have
a high (positive) depth, and foreground instances should have a low (negative)
depth.
image_xscale A scale factor to make larger or smaller images. A value of 1
indicates the normal size. You must separately set the horizontal xscale and
vertical yscale. Changing the scale also changes the values for the image
width and height and influences collision events as you might expect.
Changing the scale can be used to get a 3-D effect. You can use a value of -1
to mirror the sprite horizontally.