Index of /xtras/vsync_xtra/win

 Name                    Last modified      Size  Description
 Parent Directory                             -   
 readme.txt              2019-02-15 21:03  2.1K  
 vsync_xtra_0.2.zip      2019-02-16 00:26  140K  

-- xtra VSync
-- v0.2 (c) 2019 Valentin Schmidt

new object me

*waitForVerticalBlank object me -- returns when the vertical-blank interval begins
*waitForVerticalBlankEnd object me -- returns when the vertical-blank interval ends and the display begins
*getVerticalBlankStatus object me -- returns TRUE if currently in vertical-blank interval
*getScanLine object me -- returns scan line currently being drawn on the monitor, or integer<0 if in vertical-blank interval
*getMonitorFrequency object me -- retrieves the frequency of the monitor that the DirectDraw object controls


All functions return a HRESULT in case of failure, so if the result is <0, some
error occured.
getScanLine() returns DDERR_VERTICALBLANKINPROGRESS (= -2005532135) if it was
called during the vertical-blank interval (which is not really an "error").

For more details on all functions see
https://docs.microsoft.com/en-us/windows/desktop/api/ddraw/nn-ddraw-idirectdraw7


----------------------------------------
waitForVerticalBlank()
----------------------------------------
Function blocks until a vertical blank is reached, so calling it right before
any screen update - e.g. updateStage() - assures that the display is refeshed in
a vertical blank, i.e. without tearing.

----------------------------------------
waitForVerticalBlankEnd()
----------------------------------------
Function blocks until vertical blank ends and the display begins.

----------------------------------------
getVerticalBlankStatus()
----------------------------------------
Function returns TRUE if currently in vertical-blank interval, otherwise FALSE
(or a number <0 if an error occured).

----------------------------------------
getScanLine()
----------------------------------------
Returns the scan line that is currently being drawn on the monitor, or integer<0
if called in vertical blank interval.

----------------------------------------
getMonitorFrequency()
----------------------------------------
Retrieves the frequency of the monitor that the DirectDraw object controls, e.g.
59 or 60.