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Materials, Textures, and Finishes 
 POV-Ray Tips, 
 Tricks, and Techniques
Help With Image Maps? 
 
Dan Shookowsky explains his dilemma: I am currently trying to model a beer bottle complete with a label.  The bottle is a simple lathe object with a light brown glass texture.  I would like to use an image map for the label.  Unfortunately, to this point, I haven't had any success merging the two concepts. I know that I don't want the image tiled, just one occurrence, but I keep ending up with half bottles, or, when using layered textures, bottles that are half missing. 

Compounding this problem is the fact that Moray's coordinate system is different from POV-Ray's and the mapping is somewhat confusing.  I have read and reread the docs to no avail.  I guess what I'm looking for is a technique similar to what the POV-Ray team did with the Christmas balls on the POV-Ray page....but I'm not quite sure how to do it. Any help would be greatly appreciated.
 
Jason Peacock uses a special trick:
 One thing that could be  a problem is your imagemap.  You need to have it extend all the way around the object (that's how it's wrapped), but if you only want your image to show up on part of the bottle, then the excess of the imagemap should be created as transparent. 

********************* <-- 
*                   *   | 
*                   *   |-wraps around the neck 
*                   *   | 
*                   *   | 
*                   * <-- 
*      -------      * 
*      |IMAGE|      * 
*      -------      * 
*                   * 
********************* 
 ^^^^^^       ^^^^^^ 
   |_____________|______wraps around the sides and meets in back of bottle 

As above, the large transparent part on top would be wrapped around the neck, and the transparent parts around the sides would connect in back, but leave only the single image visible in front.  If you proportioned the transparent sides right, then the single image should appear undistorted - you have to figure this part out by trial and error - whatever looks good. 

I hope this is clear, this should solve your problem. (referring to how the christmas balls were texture-mapped - and will be the easiest way to do your bottle label).
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