Hey Christian, if you have access to ZBrush, you could load one segment and the Photoshop-cropped texture and try the "Fix seams" command.
It´ll extend the color around the UVshell borders by 4-16px. This may be enough to hide the seams. Another thing that comes to mind is the backround color of your rendermapped texture segment. Are you using the original 18Kx18K px file and just the alpha coverage file for the Photoshop action? This should prevent "pseudo-premultiplied" effects when cropping, as you don´t have black pixels as opposed to using the rendermapped texture (which will be black outside the surface area) as the cropping source. Btw, if I divide 18000px by 200, I end up with 90px that´s a very small tile and sounds like loads of interpolation to start with anyway? Cheers, tim On 18.05.2012 12:19, Christian Gotzinger wrote:
Hi list, We are dealing with a gigantic piece of environment. The ground has a texture of about 18,000x18,000 pixels applied to it. We are now in the process of dividing the entire area up into 200 quadratic segments. Thankfully, Softimage has allowed me to select all 10,000 objects at once and dice them up into quadratic segments, which I have then detached. All is good on that front. However, we would now like the 18K ground texture to be divided up into smaller segments as well. Currently all the quadratic cutouts have the same 18K texture applied but only use a fraction of their UV space. I want them all to use UV space 0 to 1 and have a matching texture. This is what I tried: I rendermapped the segments (again I'm glad to be able to rendermap everything at once) and ticked the Coverage in Alpha checkbox. I can then use a Photoshop action to select the files' alpha channel, crop down to that selection and save the file. Then I can apply the new texture to a segment, delete its old UVs and add a new 0 to 1 projection. This works, however I end up with seams of about 1 pixel width at the segment edges. Probably because the alpha coverage is not detailed enough, and Photoshop then crops incorrectly. The cropped files also have slightly different image sizes. Or maybe the rendermapping is not accurate enough? Has anybody ever done something like this? I feel like I'm 90% there, but those seams are a bit of a problem.
