The /image type contains data used to create a virtual image. Unlike other atomic objects, this object is a purely visual effect. It always appears attached to some other object and it behaves in every way as though it were part of that object (e.g. if the user clicks on it, this counts as a click on the atomic object, not the image).
One reason for creating images is player-by-player control over visibility. Images only become visible when they are explicitly output to players:
var/image/I = image('icon.dmi',usr) //make an image attached to usr
usr << I //allow usr to see itImages are also useful in the creation of overlays. Overlays are like images, since they are always attached to another object, but overlays obey the normal rules of visibility, so they are more convenient when you do not want to hide the effect from anybody. An overlay can be created directly from an icon file (or icon state), but when one wishes to override some additional parameter, the image() instruction is a convenient way to do it.
usr.overlays += image('shirt.dmi',icon_state = "red")In the above example, the icon state of an overlay was set by creating the overlay from an image with the desired icon state. Note that after the creation of an overlay, no link remains between the overlay and the object that was used to create it. If you change the image after that time, it will not change the overlay, which is simply a “snapshot” of the original image.