Thanks a lot! That was it! I'm quite new to therion but the reason is quite obvious. But there is another problem with symbol scaling (station marks)
This is strange, I have just tested following lines:
surface bitmap map.png [1335 816 400419.2 5421275.2 1781 257 401357.1 5420034.05] endsurface
and there was no complain. It worked without problems. What version of therion and OS do you use?
Hm, I tested it again today and it works now even without grid. Strange, I don't know what I did yesterday. It also seems that Therion crops the image to the layout size. Is there a way to get the whole image with the centrelines (or outlines,..) but with no additional north arrow or other layout stuff?
But now an other error occurs (dimension too large). I think it is from pdftex. I have a scan from a topographical map and specified the koordinates with UTM.
This may happen - it is already in TODO to generate some more user friendly warnings.
Therion by default generate map in 1:200 scale (for caves), which is in your case (map at 20x30km a PDF with dimensions 100x150 m. Try using
-layout-scale 1 20000
or some even smaller scale.
This works but it changes the symbol sizes of the stations also. I've added two pdfs which show the different scales. I only have the centreline data (and stationmarks) visible with some metapost code. The best would be to swich station marks off. Here the layout part of my config: layout test #scale 1 20000 scale 1 1000 surface bottom code metapost def l_survey_cave (expr p) = draw p withpen PenD withcolor (0.1,0.3,0.1); enddef; endlayout Thanks Wolfgang