Synchronise application with video refresh

[Devin_K]

pcisek,

The "Smooth Updates" property works by writing the next image to an off-screen buffer before updating the image on the front panel.  When this property is off, the current image is cleared and then redrawn, which can result in a flickering image.  Since using "smooth updates" requires the use of an intermediate buffer, it increases the memory used by an application and can result in slower performance.

[pcisek]

Devin K.

Thanks for your explanation.

Incidentally, since posting my question, I found the following thread:

http://forums.ni.com/ni/board/message?board.id=170&message.id=212084&query.id=74374#M212084

It discusses how one can implement a wait-for-vertical-refresh using ActiveX and DirectDraw functions. There are some examples posted which seem to do the job very well.

Thanks!

Paul

[Devin_K]

Paul,

Thanks for posting your findings regarding ActiveX and DirectDraw.  I'm sure that others can benefit from this information as well!