Angus Dorbie (dorbie++at++sgi.com)
Mon, 23 Aug 1999 17:11:56 -0700
The process Dick is describing is one of alignment where you render a
test pattern and use that to callibrate the display geometry. It is
something you will have to do whether you use projector or I.G. based
distortion correction.
Cheers,ANgus.
Dick Rous wrote:
>
> The only practical solution when projecting onto a spherical or
> cylindrical screen, is to "distort" the output of the projectors
> to produce a geometrically correct, continuous view, in conjunction
> with edge blending.
> To adjust the projectors, one should use a model of a wire-mesh
> sphere originated at the origin, with the viewpoint at the origin.
> I neccessary, feel free to contact me for details.
>
> Cheers,
>
> __________________________________________________________________
> Dick Rous Senior Systems Engineer Graphics Technology
> email: dick++at++sgi.com European Technical Support
> phone: +31-30-6696868 fax: +31-35-6423162 VNET: 955-6868
> __________________________________________________________________
>
> -----Original Message-----
> From: Miguel Lozano [mailto:miguel++at++glup.irobot.uv.es]
> Sent: 23 August 1999 12:27
> To: info-performer++at++sgi.com
> Subject: Distortion Correction
>
> pfHello everyone, I need some help in some "curved questions" and I hope
> you can help me .
>
> The main question is how can I correct the distortion produced in the
> projection of flat images onto a curved screen.
>
> I think there is a Sw solution (review OpenGL Advanced98 Notes) using
> texture mapping and although I donīt know exactly how to apply this
> solution, it seems to me too much expensive in terms of computational
> cost, but I'm really not sure about it .(Anyone has applied this
> solution and works fine?)
>
> I wonder also if anyone has tryed to modify the Projection matrix to
> avoid this problem, and if its also possible this kind of solution?
>
> In terms of Hw solution, anybody knows if a general Hw solution exists
> to correct this distortion?.
>
> My system consist of 3 SGI IR. and three MultiScan VPH-G70VR SONY
> projectors.
>
> Any idea about these questions would be very appreciated.
>
> Thanks in advance.
>
> -------------------------------------------------------
> Miguel Lozano Ibáņez e-mail:miguel++at++glup.irobot.uv.es
>
> Grupo ARTEC
> Instituto de Robotica Tel: +34 6 364 2253
> Universitat de Valencia Fax: +34 6 364 4841
> Poligono de la Coma s/n
> 46071 Valencia (SPAIN)
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>
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--
"One of the best-known folk theorems of software engineering is that
60% to 75% of conventional software projects are either never
completed or rejected by their intended users. If that range is
anywhere near true (and I've never met a manager of any experience
who disputes it) then more projects than not are being aimed at goals
which are either (a) not realistically attainable, or (b) just plain
wrong."
Eric S. Raymond - The Cathedral and The Bazaar
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This archive was generated by hypermail 2.0b2 on Mon Aug 23 1999 - 17:12:11 PDT