why is there a framerate drop when the renderwindow is moved to another monitor?

Feb 11, 2010 at 1:52pm

why is there a framerate drop when the renderwindow is moved to another monitor?


can somebody explain why the framerate drops when the renderwindow is moved to another monitor (driven by another graphicscard)? I observed this on os x and windows. the effect seems less significant when the output screens are connected to the first card, while the desktop is connected to the second.

the two patches are under heavy load I have to say, the settings of the metro (20ms) does not keep up with the actual framerate. the first one (as an application) drops from 48fps to 30fps, the second (inside max) from 40fps to 30fps when the windows are moved.

I am running windows 7 (I know, this is not officially supported, but as I stated, the same effect can be observed on OS X).
the windows machine has the following specs:

ASUS P6T6 WS Revolution (3 PCI Express 16x slots)
Intel Core i7 960, Quad Core, 3.2 GHz
ASUS GTX-285 1GB DDR3 (1st slot) -> 2 TrippleHead2Go attached (3840 x 1024).
NVidia GT120 (2nd slot) -> Desktopdisplay (1080p)
8 Gb Ram
2 Blackmagic Intensity cards



PS. by the way: do NOT change the resolution of the trippleHeads under windows 7. you wont be able to use them anymore unless you reinstall windows. the analog edition is not supported anymore on windows 7, but it seems to work fine with its maximum resolution.

Feb 11, 2010 at 4:28pm

Hello Martin

I have seemelar problems
See the posts


Joshua gave me a solution with connecting the message “; jitter glreadback fbo”

Maybe it would work for you as well

Feb 11, 2010 at 5:53pm

sounds like you just need to rebuild the render context after repositioning the window.

actually, “; jitter glreadback fbo” will rebuild the context, but i’m not sure if fbo readback is going to be the best choice for your graphics card.

i would try simply rebuilding by toggling the “floating” attribute of your jit.window and see if that fixes the framerate. after that, try fbo readback.

Feb 11, 2010 at 6:42pm

yeah i have had some funny stuff happen with changing border and floating attributes while rendering and turning off the render while making changes avoids them for me.

Feb 14, 2010 at 6:36pm

Thank you all for your tips and hints. the described phenomenon has vanished after the update to max 5.1.3. But maybe it was a change in my patches, using jit.gl.texture for the jit.gl.sketch object instead of the provided example in the help file, where the (movie-matrix)texture is sent to the jit.gl.render object (prepend texture ) and beeing used by sketch via the message “texture “.

With the above hardware I am capable to render openGL output to 6 beamer (each 1280 x 1024) via 2 tripplehead2gos, capturing HDMI 720p50Hz with 2 intensity cards and using them as textures for sketch objects. each capture card and tripplehead2go runs inside a seperate patch (exported as application) with a steady 50fps.

a result of this setup can be seen here: http://projektil.ch/129-0-tonhallelate.html

Feb 14, 2010 at 7:01pm

hello t0gg1e4u,
same problem here.
sounds interesting but i did not understand, how you get
the texture from the jit.gl.texture to the jit.gl.sketch.

it would be great, if you could post a smal example.

thnk you in advance.

Feb 14, 2010 at 7:08pm

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