Graphic objects are the main VRR kernel objects. Each one (except for groups) represents a graphic element in the image. The geometric dependency structure is stored in the objects using anchors and hangers. Anchors provide “geometric input” for the objects, whereas hangers are “geometric output” devices. The set of hangers is the same for all graphic objects of the same type; the anchor set can differ for subtypes.
A hanger has a list of hangers which hang on it; an anchor contains a pointer to the one hanger it hangs on. There are several types of hangers:
A list of all the supported graphic objects follows.