rpniponal Posted April 24, 2009 Share Posted April 24, 2009 I was wondering if there is a quick way of inverting a polygon. I have a 2D drawing of polygons that I want a "negative" version of. Ideally I would be able to draw a rectangle that encompasses all of my polygons and run a command that would then create the subsequent polygons that make up the negative of my drawing. I've drawn some cartoons to illustrate my point. My drawing would be the circle, and I draw a rectangle around it. The subsequent command would be able to create the inverted polygons. It also breaks the rectangle up to ensure that all polygons don't have "holes" in them. This is a requirement. Is there a simple procedure for what I am trying to do here or am I stuck doing this by hand? Thanks, Phil Quote Link to comment Share on other sites More sharing options...
ReMark Posted April 24, 2009 Share Posted April 24, 2009 Sounds like you might be in need of a lisp routine. Quote Link to comment Share on other sites More sharing options...
Lee Mac Posted April 24, 2009 Share Posted April 24, 2009 This would be a pretty complex task, even for a LISP routine... Quote Link to comment Share on other sites More sharing options...
ReMark Posted April 24, 2009 Share Posted April 24, 2009 Don't let the above post fool you. Lee Mac just loves a challenge. He'll probably knock this off over his snack break while concurrently doing the New York Times crossword puzzle. The guy is just amazing. Quote Link to comment Share on other sites More sharing options...
NH3man! Posted April 24, 2009 Share Posted April 24, 2009 LMAO I believe you ReMark! Quote Link to comment Share on other sites More sharing options...
Lee Mac Posted April 24, 2009 Share Posted April 24, 2009 Haha, thanks ReMark But I am a little stumped on this one tbh.... :unsure: For Example, in the instance attached, how would the pieces be broken up? Into 3? also, with the multitude of entities that could lie inside the rectangle you draw, how does one know where to break each one? Quote Link to comment Share on other sites More sharing options...
ReMark Posted April 24, 2009 Share Posted April 24, 2009 Good points Lee. It could get quite complex. Perhaps the OP can expand a bit on the purpose behind the request. Quote Link to comment Share on other sites More sharing options...
rpniponal Posted April 24, 2009 Author Share Posted April 24, 2009 Yeah, I am seeing that most geometries would have more than one solution, as Lee Mac points out. I had hoped this was a simple command I wasn't aware of, but now that I know that I think it would involve something akin to taking every side of each polygon and tracing out new lines to the bounding box ( simplify the problem and state the outer polygon is always a rectangle). Of course it wouldn't just be to the bounding box, it would be to the nearest side, be it the bounding box or another polygon side. The purpose of this is that we have a photolithography mask drawn in the positive, and now we want the same mask drawn in the negative. As in we've drawn closed polygons where we want the mask to be opaque and now we want an equivalent drawing that would have the opposite area of drawing opaque. This can easily be done by just changing the process by which the mask is made, but I want the same features drawn in negative and positive on the same mask. Quote Link to comment Share on other sites More sharing options...
Lee Mac Posted April 24, 2009 Share Posted April 24, 2009 Can you not utilise the "group" command? Quote Link to comment Share on other sites More sharing options...
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