Rounding errors?

[David Kuehling]

Hi,

I'm currently creating a poster for some student project, using Lout.
Using concatenation operators, it is really simple to put content
well-aligned onto a large page of paper.  However, I'm repeatedly having
problems where Lout seems unable to deduce the right size of boxes etc.

Unfortunately Lout seems unable to handle page sizes much greater than
A3. Some kind of overflow errors?  Well, I typset my document in A3
(landscape) using 9point font, so later after scaling to A0, everything
should look right.

My document structure is something like:

  39c @Wide @ShadowBox @HExpand { 
    <Title>
  }
  //.5ce
  {
    10c @Wide 11c @High @ShadowBox {  
      @HExpand @VExpand { 
        {} ||.03ce { some content } ||0.3ce
      } 
    }
    //.5ce
    10c @Wide 11c @High @ShadowBox {  
       ...
    }
  } ||.5ce {
    17c @Wide 5c @High @ShadowBox { ... } 
    //.5ce
    ...
  } ||.5ce {
    11c @Wide 11c @High @ShadowBox { ... }
  }
  
As you can see, it's quite deeply nested.  Still, just from looking at
it, I'm able to see what height etc. will result, so that shouldn't be a
problem for Lout as well.  With the vertical columns' width as written
above, Lout outputs an error:

  poster.lout:124:11: 0.7c object too high for 0.7c space; will try elsewhere

The document is still generated, but line breaking is wrong in the
middle column.  Seems like Lout broke the lines twice.  First just
normally, and then a second time to break lines that were still too
long.  Maybe since the double-broken lines took up too much vertical
space in the box, that error message appeard.  I've put a
well-compressed PDF (59k) of the current state of the Poster here:

  http://user.cs.tu-berlin.de/~dvdkhlng/brokenposter.pdf

If I reduce the middle column's width by some small amount (.1cm) it
looks right again.  BTW the text that's broken wrongly is contained in a
deper nesting-level, as it is split into two columns within the
shadowbox:

    { text1 } ||.5ce { text2 } 
    //
  
I saw the same error before (without any Lout errors during postscript
generation!), with descriptions that I had put below two images aligned
besides each other within one of the @ShadowBox'es:

    @DP
    4.25c @Wide { 
      @Scale @IncludeGraphic { "..." } //.1ce
      0.8f @Font @I { results retrieved via cross-correlation }
    } ||.5ce
    4.25c @Wide {
      @Scale @IncludeGraphic { "..." } //.1ce
       0.8f @Font @I { results retrieved via CCA }
    }

That error vanished after I did some restructuring.  What's wrong here?

Any tips on how I can prevent such errors?  Is my structuring somehow
wrong?  I want to print the the poster on monday morning and really hope
that I'm not running into unsolveable problems with the remaining
content I want to put on it...

BTW, I'm using Lout version 3.29

regards,

David
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