Gem_719 opened this issue on Apr 21, 2001 ยท 8 posts
Gem_719 posted Sat, 21 April 2001 at 5:07 PM
I created a simple object in RayDream using primitives (a cube and 3 cylinders, with the cylinders subtacted from the cube with boolean operations, resulting in a shallow rectangle with three arches cut into it) and exported it as an .obj file. I tried using UV Mapper to create the texture map but it seems that no matter what options I used, the result leaves the texture scattered all over the object. (I tried in both Poser and Bryce.) The UVM map option that seemed to make the most sense was to use Box since the object was still basically rectangular. I tried combinations of all of the three options for Box, and the resulting maps looked good, but still they wouldn't map right in Poser or Bryce. And, yes, I did remember to export the "new" .obj file from Mapper and used it with the new texture maps. I tried using both the .24d and .25c beta versions. Any help out there?
twillis posted Sat, 21 April 2001 at 9:12 PM
Dunno if this is the problem you're having, but sometimes I have better luck with the UV Mapper if I use Open and Close instead of Import and Export.
wyrwulf posted Sun, 22 April 2001 at 12:30 AM
I don't know what to tell you to try. I've never had a problem like you describe. If you want to send the OBJ to me to try, let me know. I've had pretty good luck with UVMapper. You might contact Steve Cox (the author of UVMapper). He is very happy to help with any problems.
Gem_719 posted Sun, 22 April 2001 at 12:58 PM
Attached Link: http://www.geocities.com/gem_719/poser_zip_files/UVMproblem/UVMproblem.html
twillis, my versions of UVM do not have open and close. cutcopypast, and anyone else who'd like to take a crack at it, I posted a zip file containing the obj from RD and the texture from UVM, as well as illustrations to make it clearer, on a web page here: http://www.geocities.com/gem_719/poser_zip_files/UVMproblem/UVMproblem.html I'd appreciate any assistance. I plan on contacting Steve Cox as well. Thanks for the input so far.twillis posted Sun, 22 April 2001 at 1:21 PM
Yeah, sorry I wasn't more clear.
Gem_719 posted Sun, 22 April 2001 at 2:57 PM
Steve replied to my email. Here's what he had to say: "I've run into this problem with RayDream before. The reason it's happening is that when you perform a boolean function in RayDream, the facet winding order gets all mixed up (RayDream does not take care to be sure the facets are all facing the right way after the operation.) Winding order is what UVMapper uses to determine which way a facet is facing and where it should be mapped when splitting an object using planar or box mapping. If the winding order is inconsistent, the results in UVMapper will probably not be what you expect. This problem is a little more apparent if you do a box map and split the box into 6 sides (the default setting.) I've been thinking about adding a feature to UVMapper that will run through all the facets in a model and guarantee that the winding order is consistent (to help when other programs don't seem to care about this) but haven't had the time yet. Hopefully before long I can get this done." So, it appears that there is no solution to this problem at present using UVM with Ray Dream. I had planned on using RD to create a complex interior room with elaborate texture mapping, but, if I can't solve this problem, I might as well put a hold on it until Steve makes the change he mentioned. Thanks for your time people. If anyone has any more ideas, I'd appreciate it.
Gem_719 posted Sun, 22 April 2001 at 5:39 PM
cutcopypaste - many thanks for the tutorial. I can't wait to try it out, but can't just yet. I will tomorrow. I'll let you know how it goes. Too bad about the booleans tho, my project is architectural in nature and therefore chockfull of candidates for using that technique. I've never tried the method you just explained (brand new to RD) but it looks like it might work for me for most circumstances anyway. Thanks again.
Gem_719 posted Tue, 01 May 2001 at 11:00 AM
Been busy and it's taken me a while to get back to this, but, here's what's been happening. cutcopypaste: Your directions were great, very easy to follow, and I created the object in no time. However, even tho the map worked better this time, the object showed this strange shading effect where RD left the facets turned the wrong way. This was apparent even with no texture map applied. So, okay, I thought, lofting didn't work, what else could I try? What about extruding or thickening? Tried both. Same problem with the facets for both. Totally frustrated by now, I was about to give up and go out and buy Maya when I came across a short paragraph in the "ray Dream Handbook" titled "Use a Drawing Program" (pg. 87). It noted that you could use an outside program to create the 2D shape and import it into the free form modeler. I had Adobe Illustrator so I tried it. Shazam! It worked! No more naughty, twisty facets! I still have an issue with the way that UVM handles the mapping on the curves (it seems to use the top/bottom part of the texture for the more horizontal parts of the curve, and then it switches to using the side portion of the texture map on the more vertical parts of the curve). I'll contact Steve Cox about this. Thanks to all for your help.