pROjector Node and spectator view



i have calibrated my projector on a geometry and i’m using the patch from the wiki to achieve the parallax effect for different spectator positions. but moving the spectator also damages the calibration and on no 3d content as well.

tweeking the spectator position, orientation and throw ratio of the projectornode that simulates the spectator ussualy gets me somewhere but
i cant always get the exact desired position.

i’m wondering if there are some correct values to feed the projector node in order to simulate correctly.or maybe a different view tranformation node other than the projector.

i hope i’m making some sense here

that’s it,thanks


the changing of the spectator position shouldn’t effect the calibration of the setup. It can effect what is textured on your model though if the spectator can’t ‘see’ the whole of the building, or atleast the part you’re trying to cover with that projector. if you have everything setup correctly, changing the zoom of the spectators view won’t effect the content on the building (effective resolution of the texture will change).

have a check of your patch and post it on here if your still having problems.


hi xdnitro , thanks for replying.

u r right about the zoom ratio. it doesn’t effect the calibration but it’s the only parameter that doesn’t. lens shift and other parameters do though.

i could send my patch but is nothing more than a basic two projector setup calibrated on a model.(wiki patch)

also the effect of the spectator view parameters are exactly the same for both calibration isn’t the perfect one but is prettyclose.

is there a way to make a patch to prove what i’m saying.?



hey, i am using the same patch, the thing is that i set the projectors and everything but moving the spectators view is changing the texturing of the building ! anyway this is one problem, the second problem is that i am using a quad with a video stream to texture the desired projected video on the mesh but im the quad (video)always seems to have a weird perspective which mean trapeze shape…

conclusion: i am putting the spectator projector where the spectators will be during the show but im not having a good result because it is hiding changing the texture !

what to do ?


ok. moving the spectators position will effect the texture on the model because it’s this view that is being textured on the model. But it certainly shouldn’t effect the calibration of the projectors. certainly rotating or zooms won’t change what is textures on the building as long as the spectator can ‘see’ the whole of the model.

@levi, the spectator projector parameters have nothing to do with the projector parameters used the represent the projectors you are using. They may be similar if it so happens that the spectators view is around the same place as the projectors them selves. the two projector setup in the wiki worked for me so I’m not sure what your issue is. Are you sure you have an issue? projector calibaration should no be effect by adjusting spectators view. If you set you’re model to wireframe it should fit your model, now adjust the spectators view and it shoouldn’t change things. Remember you’re texture on your model will only look correct from the spectators view point (obviously).

@omar, if you want video to texture you’re building correctly, you don’t want to be using the spectators projector technique. all you need to do is get the right UV texture mapping for the model done in your 3D software and then apply the video texture straight to it.