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Vvvv render window - no signal on 2nd monitor

Hi
I’m trying to record my vvvv action on an external camcorder, but i am stifled by this odd behavior: the render window will appear on the external monitor, but not the animation inside the window. It is simply blank. Other (non vvvv) windows appear to be behaving normally. So i think this must be a problem of 3d display on my graphics card.
Admittedly I am using an older card (Radeon 7000 - signal viewed through the s-video port).
Also, the machine i am using is a dual quad core processor. Maybe that is the problem?
Can this be adjusted from within vvvv? Could there be a special node that might enable 3d visibility?
I ran into a similar problem once when i was doing 3d video feedback in director 3d, which required to put the 3d sprite property ‘direct to stage’ =0. This allowed one to route the video signal back onto a texture, but it also removed some of the 3d graphics resources, so the 3d would not play on the extenal monitor. Since I am also using 3d video feedback in my vvvv patch, i thought there might be something similar going on here. Is there any way to adjust the controls for 3d performance on the graphics card? I couldn’t find anything like this on the radeon card.
Perhaps i need to get a new video card. Anyone have any good recommendations for a great game card that has reliable video out through the s-video port?
thanks

Thomas

ai diatom,

if you have the chance, do yourself a favour and get a new graphiccard. that will most likely solve your problem. take any of the newer nvidia cards that fits your budget.

also for recording fullscreen output i’d once again recommend fraps which is cheap and will provide you with far superior quality than recording via an analogue output.

Thomas,

I ran into this same problem when trying to make a video mixer with a preview on my laptop, then running the output from the preview renderer to a renderer on a projector. Basically, if you are playing a video stream into a renderer on one monitor and try to display the same video stream in a renderer on a second monitor, you will just get the blank window you describe.

The only way I was able to get this to work finally was to actually have two identical streams running simultaneously, and manually re-syncing the playback if the frame difference exceeded a maximum threshold. This is a really poor solution, however, since it doubles the bandwidth overhead of each video channel in the mixer, and starts behaving very strangely after about 30 minutes of continuous playback.

If any of you VVVV pros can find a better solution, I would love to know what it is!

Parker

as far as i know the problem parkerault describes is a limitation of graphics/directx: you can’t play a video (e.g. as a texture on a quad) on two monitors simultaneously. 3D/non-video material shoud be fine, though. so if parkerault gets rid of the preview monitor on his laptop, the other renderer shoudl play fine (not a perfect solution, i know).

it may be that the problem diatom describes is also based on this behaviour. if so, i think a new video card wouldn’t solve it, am i right, joreg?

one approach to deal with this (admittedly more relevant in connection with multimonitor setups), is using the “span mode” of your graphics card. search the forum, you’ll find material on this, maybe it helps you solve your problem…

yo, we are mixing up different things here.

  • videotexture
    diatom didn’t mention anything about playing video on the second monitor. it is true, that vvvvs videotexture will always only be visible on one device (where you need to note that spanmode is indeed one device via multiple monitors). so the videotexture is one problem.

  • dx9texture
    a similar problem is caused by the dx9-texture that would only show things on one device. this should be fixed though for beta>14

  • old cards/drivers
    from what diatom described i thought it would be this category. a radeon7000 sounds really old. i doubt they provide recent drivers for those and a general dx-not-running-on-multiple-devices bug seems likely to me. (at least this is always the first guess of a programmer…)

Hey everyone

thanks very much for all your help.

I just got a new card and tried this again and i ran into the same problem. It is exaclty as parkerault says: the 3d render window works fine when there is no video feedback, ie the render output does not get fed back into a texture and back onto a suface. But once i try to use 3d feedback (as in the trees demo) the 3d display freezes. So indeed this does not have anything to do with using older video cards but is result of using video feedback. There must be something about routing the renderer into a texture that alters the way the signal goes to the analogue video out. My guess is that this is something equivalent to ‘direct to stage’ in lingo, in that the hardware resources must be changed to allow for screen capture, and this effectively bypasses the analogue video out.

So it seems that analogue video out is not a good choice in any case. For recording, better to use Fraps (thx for that! brilliant!).
For screen projection, its better to use the VGA signal from the second monitor. The only problem here has to do with the length of the VGA cable, which are usually quite short. Perhaps long cables can be found and will work? Another workareound would be to use an vga to analogue converter and then send the signal over a long cable to a projector.

So it seems all the problems are solved.
Thanks very much!!!

thomas

as mentioned above if you are using dx9texture there is a bug in the current version which should be fixed with the upcomming version.

if it is this bug you should be able to workaround though: make sure that you don’t have any renderer-window on the first monitor. close them all or move them to the second monitor (so that they are behind the fullscrren output)