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hwj_just
05-16-2005, 05:19 PM
hello i define a 3d texture from a stack of dicom images,when using one CT image to difine a 3d texture i can get correct result.but when use two CT images to define a 3d texture i get a wrong result, and above three the result only a white square.anyone who can give me some advice of the problem?thank you very much!

dorbie
05-16-2005, 11:27 PM
Above 2 you may be running out of space but remember all axes must be 2^n in size.

The errors you think you see may be the result of interpolation. Try a nearest filter and/or clamping and remember that texture wrap when a coordinate = 0 will give you a 50%/50% weighting between the two samples on any axis that has only two samples stored. Clamping in conjunction with understanding your sampling in 3D will probably resolve your issues.

hwj_just
05-17-2005, 03:17 AM
now i know that because of all axes must be 2^n in size ,i only can use 2^n CT images to form 3d texture.and that's right now.but i found when using 2 images, the result seems to be enlarge and the image be break up to four cornor.and image quality become bad .when using 4 images it distort much severity,when using 8 or 16 image to form a 3d texture it seems only render a little area of initial image.what is the matter?thank you !

ZbuffeR
05-17-2005, 05:51 AM
screenshots, please

hwj_just
05-17-2005, 04:51 PM
how to put the image here?i try but i failed