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Hi all, this one is for all the metapos/metafun experts out there (Alan, are you there?). For a counter in one of my slide backgrounds, I have to calculate an intersectionpoint, given in percentage of the difference between current page and last page. I have always had some difficulties on the first run, when the value of the last page isn’t known yet and hence not written to the tuc file, but the error
! The paths don't intersect. <to be read again>
used to disappear in subsequent runs. Now, ConTeXt doesn’t compile the file at all and stops on this error. There is an error message I haven’t seen before:
intersectionpoint->...The paths don't intersect"); origin.else:0.5[point.x_.o... <to be read again> ; <*> ... ;z13 = (z11 -- z12) intersectionpoint qw ; draw z13 withcolor (0.1,0.... This error message was generated by an `errmessage' command, so I can't give any explicit help. Pretend that you're Miss Marple: Examine all clues, and deduce the truth by inspired guesses.
Is there a way to make this conditional, such as (pseudocode) if q intersects p: z = q intersectionpoint p ; else: z = (0,0) ; fi ; I hope that this would allow ConTeXt to proceed and calculate the point correctly on the second run. Thanks, and all best Thomas