On Thu, 18 Aug 2005 00:10:01 +0100, Wookey wrote
I used to have scale 1 2000 base-scale 1 1000
in my layout. That worked OK, but the symbols were very small and the text was microscopic.
They were printed in 1/2 size because of base-scale setting.
So I added code metapost fonts_setup(10,16,20,24,28)
And that made the text a sensible size.
I just changed base scale to read base-scale 1 2000
which makes the symbols a much more sensible size, but makes the text too big.
If the base-scale is equal the scale, it has no effect (such as 1:1 photocopy) . The text was large because of your fonts_setup setting.
My understanding of these two values is that scale sets the scale of the output (i.e how big the final PDF sheet is in map mode, or how many sheets in atlas mode) , whilst base-scale 'has the same effect as if the map printed in base-scale would be photreduced to the scale' (quote from thbook)
You may forget the base-scale if the default settings work well. We introduced the base-scale to make it possible to do simple adjustments to the size of symbols used without the need of metapost programming (e.g. when symbols appear too big in the 1:400 scale, but OK in 1:200 scale, it's enough to set base-scale 1 200 and scale 1 400 and I get map in 1:400 scale with symbols proportionally as large as on 1:200 map)
But if it was photoreduced then the fonts and symbol size shouldn't change.
I think photocopy 1:2 changes everything to be 1/2 smaller
So I am confused about how this should work. When would I ever want scale and base-scale to be different? Why does changing base-scale effect the size of symbols and text?
See above. If therion gives you suitable symbol sizes, use only scale setting. If not, experiment with base-scale or redefine metapost.
On a related point I tried doing an atlas version with the defaults (i.e. 1:200) and get loads of 'number too big errors' from metafont.
I can see why such a scale is a problem in map mode (page larger than PDF can manage), but in atlas mode the page size is limited to A4 (or whatever) - so why can I not print an atlas (with a lot of sheets) showing the system in high detail? Is it a fundamental problem of the way the PDFs are generated or can it be fixed?
An additional limitation is the size of a picture, which can metapost process -- it's about 2.8 m. Each scrap is processed separately in one picture, so it means, that each scrap must be smaller than 2.8 * 2.8 m _in the output scale_. I don't think it's a big issue unless you try to draw the whole cave in one scrap. (At 1:100 scale a scrap can contain 280*280 m section of the cave). Atlas size (and SVG map size) is unlimited. Martin