| A framework to manage display attributes of interactive objects. An interactive object can have a certain number of display attributes specific to it. These include visualization mode, color, material and so on. To deal with this information, the interactive context has a Drawer attribute manager which is valid by default for the objects it controls. When an interactive object is visualized, the required graphic display attributes are first taken from its own Drawer if it has the ones required, or from the context drawer for those it does not have them. The set of display attributes of an interactive object is stocked in an AIS_Drawer, which is, in fact, a Prs3d_Drawer with the possibility of a link to another display attribute manager. This drawer then manages the stocked graphic display attributes by specifying how the presentation algorithms compute the presentation of a specific kind of object. These factors involved include color, width and type of line, and maximal chordal deviation. The Drawer includes instances of the aspect classes providing the default values for them. Prs3d_Drawer completes AIS_Drawer by adding functions for setting deviation angle and deviation coefficient in presentations using hidden line removal. More...
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