Thanks, anyway I need to add the alpha channel only during a preprocess stage while the shader approach will do it every time I draw a frame, I guess.
I found a post that suggested to 'change/set' the internal format to something like RGBA if the image is not already in that format, but then I wonder how to access the content/channels of the image...am I supposed to manually read the _data member (that is unsigned char*), extract RGB values and modify it accordingly? Thanks Alessandro On Tue, Jun 1, 2010 at 8:35 AM, J.P. Delport <[email protected]> wrote: > Hi, > > have a look at the render to texture examples (grep for "attach"). You > create an RTT camera, attach your RGB texture as input, create an RGBA > output texture and attach this as the output, then in a shader do your sums. > > jp > > > On 31/05/10 18:15, alessandro terenzi wrote: > >> I have an Image coming from a texture, and I'd like to add an alpha >> channel with values that are an average of the corrensponding pixel RGB >> values. Is there any example that could help? >> >> Thanks. >> Alessandro >> >> >> >> _______________________________________________ >> osg-users mailing list >> [email protected] >> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org >> > > -- > This message is subject to the CSIR's copyright terms and conditions, > e-mail legal notice, and implemented Open Document Format (ODF) standard. > The full disclaimer details can be found at > http://www.csir.co.za/disclaimer.html. > > This message has been scanned for viruses and dangerous content by > MailScanner, and is believed to be clean. MailScanner thanks Transtec > Computers for their support. > > _______________________________________________ > osg-users mailing list > [email protected] > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org >
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