In release 2.0, Intuition fully supports video overscan. There are four standard overscan specifiers: OSCAN_TEXT, OSCAN_STANDARD, OSCAN_MAX and OSCAN_VIDEO. OSCAN_TEXT is based on user preference settings and indicates a display which is within the visible bounds of the monitor. The dimensions of this type of overscan are used for the Workbench screen and for the defaults for OpenScreenTagList(), STDSCREENWIDTH and STDSCREENHEIGHT. OVERSCAN_STANDARD is also based on user preference settings. The edges of an OVERSCAN_STANDARD display are set by the user via Preferences to be just outside the visible bounds of the monitor. OSCAN_MAX is the largest display fully supported by Intuition. OSCAN_VIDEO is the largest display region which, for a given display mode, can be reliably generated. Note that OSCAN_VIDEO displays are not scrollable. The Intuition function QueryOverscan() returns rectangle information for the indicated overscan type of a particular display mode. Using the rectangle returned by QueryOverscan(), it is possible to explicitly specify the offset and dimensions of the DisplayClip region. Note however that this custom rectangle must fit within the OSCAN_MAX rectangle, offset included. It is not permitted to specify custom rectangles whose values are in between OSCAN_MAX and OSCAN_VIDEO, nor is it permitted to specify rectangles larger than OSCAN_VIDEO.
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