I'm trying to say that I can't figure out what should loopless lines look like. The criteria currently used in clean_parallel() is bad, cause it removes loops, for which common sense says they shouldn't be removed. (See my triangular loop example with parallel line on the right. Currently clean_parallel() removes the formed loop). I doubt that there is sensible criteria for removal of loops. That's why I'll remove the "-l" option (for now and probably forever) and then I'll work on type B/C lines.
Rosen On Thu, Jun 19, 2008 at 3:25 PM, Wolf Bergenheim <[EMAIL PROTECTED]> wrote: > On 18.06.2008 22:24, Росен Матев wrote: >> >> Hi, >> >> I propose that I cancel development of "clean_parallel()" (the >> function which removes loops), cause its proper behavior is not >> determined now (and it might not be possible to determine it). >> Instead, I'll start making function which generates "type B" lines, >> which will be more useful in buffer generation. What do you think >> about it? > > I still think that both A and B have merit, depending on what you want to do > with the parallel lines. If it is meant to mark the the side of the road > that gets cleared for installation of say phone wires, and all lines go in > the direction of the traffic, then A is the way to go. If you want to make > buffers then B, no sorry C (B with holes), is the correct way to go. Once > you are dine with making parallel lines according to B you need to go > through the original line again to find loops and for those loops punch > holes. > > As for the loop removal, ell if you can produce a function that can produce > loopless parallel lines, then by all means drop clean_parallel(). Note that > the the previous problem case also needs to work ;). I'll also ponder on the > parallel line algorithm. > > Another way to go would be to emulate a CNC machine and place a circular > "tool" on top of the line and calculate a tangent at each corner to connect > two balls on the left and right side. But that might actually be harder then > going via parallel lines. I'm not sure. But it would allow for all kinds of > interesting buffer shapes. > > --Wolf > > -- > > <:3 )---- Wolf Bergenheim ----( 8:> > >
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