NAME
QueryOverscan -- Inquire about a standard overscan region. (V36)
SYNOPSIS
success = QueryOverscan( DisplayID, Rect, OScanType )
D0 A0 A1 D0
LONG QueryOverscan( ULONG, struct Rectangle *, WORD );
FUNCTION
This function fills in a rectangle with one of the system
overscan dimensions, scaled appropriately for the mode of
the DisplayID it is passed.
There are three types of system overscan values:
OSCAN_TEXT: completely visible, by user preference. Used
for Workbench screen and screen dimensions STDSCREENWIDTH
and STDSCREENHEIGHT. Left/Top is always 0,0.
OSCAN_STANDARD: just beyond visible bounds of monitor, by
user preference. Left/Top may be negative.
OSCAN_MAX: The largest region we can display, AND display
any smaller region (see note below).
OSCAN_VIDEO: The absolute largest region that the graphics.library
can display. This region must be used as-is.
INPUTS
DisplayID -- A 32-bit identifier for a display mode, as
defined in graphics/displayinfo.h.
NOTE: If you only intend to use one of the four standard
overscan dimensions as is, and open your screen to exactly
the DisplayClip dimensions, you can specify one of
the OSCAN_ values in the ExtNewScreen tag SA_StdDClip,
and specify STDSCREENWIDTH and STDSCREENHEIGHT as the
dimensions to more easily open up an overscanned screen
(or use no NewScreen in OpenScreenTagList() and accept
the default standard screen dimensions).
Rect -- pointer to a Rectangle structure which this function
will fill out with its return values. Note that to convert
a rectangle to a screen "Height" you do (MaxY - MinY + 1), and
similarly for "Width." The rectangle may be passed directly
to OpenScreen() as a DisplayClip region (SA_DClip).
RESULT
0 (FALSE) if the MonitorSpec your NewScreen requests
does not exist. Non-zero (TRUE) if it does.
BUGS
Change in parameter V36.A17 might cause problems for some.
SEE ALSO
OpenScreen(), Intuition V36 update documentation
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