The author did a lot of coding and encapsulating in order to come up with a cSprite child class called cSpriteIcon. cSpriteIcon has a constructor cSpriteIcon(int resourceID) which takes the ID of a bitmap resource as its argument. To make things nicer, the cSpriteIcon will automatically make the background of the image transparent. To give a critter a transparent-background sprite based on a resource bitmap with an ID like, say, IDB_EARTH, we only need to add a single line to the critter’s constructor.
We also have the option of not having a transparent background at all. The full prototype of the cSpriteIcon constructor looks like this.
cSpriteIcon(int resourceID, BOOL transparent ...