Abstract: Object sets are often organized and traversed in a hierarchical manner according to ownership, wherein a subset of contained objects are processed before or after a containing object that contains the contained objects. Such object sets may also be presented as a scene, which may involve traversing the object set in a drawing order, such as a descending distance order that renders objects in a back-to-front manner. It may be difficult to reconcile these distinct traversal techniques, particularly if different portions of the object set utilize a different traversal order. Presented herein are hybrid traversal techniques in which a selected subset of related objects is identified and traversed in a drawing order, and the remainder of the object set is traversed in an ownership order, in furtherance of various tasks that involve hybrid traversal orders and/or to facilitate the traversal of different types of object subsets within the object set.

Abstract: Scenes of objects, such as models in three-dimensional environments and user interface elements in window-based computing environments, are often rendered with shadows cast by a first object on a second object based on a light source. Full graphics engines often produce rich and high-fidelity shadows but involve extensive computation that may be unsuitable for some lower-powered devices. Simple shadowing techniques, such as drop shadows, may be rendered with modest computational processing, but only within significant restrictions and with poor fidelity. Presented herein is a shadow rendering technique that involves identifying a silhouette cast by an object due to a light source and applying a geometric transform, based upon the positions of the objects and the light source within the scene. The shadows may further include variations for opacity and/or edge blurring, reflecting distances between the light source and the objects, and colored shadows that exhibit translucency as a stained-glass effect.

Abstract: Object sets are often organized and traversed in a hierarchical manner according to ownership, wherein a subset of contained objects are processed before or after a containing object that contains the contained objects. Such object sets may also be presented as a scene, which may involve traversing the object set in a drawing order, such as a descending distance order that renders objects in a back-to-front manner. It may be difficult to reconcile these distinct traversal techniques, particularly if different portions of the object set utilize a different traversal order. Presented herein are hybrid traversal techniques in which a selected subset of related objects is identified and traversed in a drawing order, and the remainder of the object set is traversed in an ownership order, in furtherance of various tasks that involve hybrid traversal orders and/or to facilitate the traversal of different types of object subsets within the object set.