Re: How-to set resolution for png export?

[Hans Breuer <hans breuer org>]

At 02.04.2009 18:51, Lars Clausen wrote:
> On Apr 2, 2009, at 6:31 PM, Richard Moll wrote:
[...]
> > > > In the help I found the command line syntax, which unfortunately 
> > > > doesn't work either:
> > > > C:\...>dia --export=test.png --size=600x --filter=png test.dia
> > > > Notice: User Interface type settings change will take after restart
> > > >
> > > > ** (dia.exe:2948): WARNING **: --size parameter unsupported for 
> > > > cairo-png filter
Yes, it is a hack not supported for any filter except png-libart.
The message tries to tell you so:



> > > > test.dia --> test.png
> > > You will need to compile Dia with libart support (if the Windows 
> > > version isn't already), and then use the PNG(Libart) export a.k.a 
> > > --filter=png-libart
> > Seems that currently there is no libart support:
> > ** (dia.exe:5628): CRITICAL **: Can't find output format/filter 
> > png-libart
I doubt this, but you can check yourself. If libart was available during
compile time  there is mentioning of it in the command line help:

Usage:
  dia.exe [OPTION...] [FILE...]

Help Options:
  -?, --help                            Show help options
  --help-all                            Show all help options
  --help-gtk                            Show GTK+ Options

Application Options:
  -e, --export=OUTPUT                   Export loaded file and exit
  -t, --filter=TYPE                     Select the filter/format out of: cgm, di
a, dxf, eps, eps-builtin, fig, mp, plt, hpgl, png (png-libart, cairo-png, cairo-
alpha-png, pixbuf-png), jpg, shape, svg, tex, wmf, wpg
  -s, --size=WxH                        Export graphics size
  -L, --show-layers=LAYER,LAYER,...     Show only specified layers (e.g. when ex
porting). Can be either the layer name or a range of layer numbers (X-Y)
  -n, --nosplash                        Don't show the splash screen
  --nonew                               Don't create empty diagram
  -l, --log-to-stderr                   Send error messages to stderr instead of
 showing dialogs.
  -I, --input-directory=DIRECTORY       Directory containing input files
  -O, --output-directory=DIRECTORY      Directory containing output files
  -c, --credits                         Display credits list and exit
  --verbose                             Generate verbose output
  -v, --version                         Display version and exit
  --display=DISPLAY                     X display to use

> > Unfortunately I don't know how to compile anything...
> >
> > Maybe Steffen would be so kind? :-)
> > I (and I guess many other Win user too) would be very grateful!
>
> That'd be where it'd have to happen - if libart even compiles on Windows.
It is available for years, but I doid not check if the current installer
still does include it. (See above).

> > PS:
> > In the GUI I can also choose pixbuf[png]. However, I couldn't figure 
> > out the format option (png-pixbuf doesn't work) 
again the command line help will give you the answer

> and I also don't know if it does support the size option.
It does not. See above.

> Same as cairo-png, does not support size. Shouldn't bee too hard for an 
> incoming programmer to snatch the size code from libart-png and apply it 
> elsewhere.
Sorry, the same hack as done for libart is not acceptable (pixbuf and cairo
filter need their 'user_data' to select the format, as original intended).
But at proper solution should not be too difficult either. Just some small
extension in the  exporter interface would be needed.


        Hans

-------- Hans "at" Breuer "dot" Org -----------
Tell me what you need, and I'll tell you how to
get along without it.                -- Dilbert