Re: backend and format - difference?

[David Feuer]

On 4/13/06, Bertalan Fodor <address@hidden> wrote:
> Hello,
>
> what is the difference between backend and format (-b and -f switches).
> I see confusion.

This is not the clearest part of the interface.  Each backend knows
how to convert LilyPond's internal engraving representations (called
stencils) into a different basic output language.  The format controls
what exactly is done with that basic output.  PNG, for example, could
be produced by the PostScript backend by first producing a PostScript
version and then running it through GhostScript to produce the PNG. 
I'm not too clear on how the -b settings correspond to the actual
backends.  As I understand it, there are five backends:

GNOME: I haven't looked into this one yet, but it's apparently not
being actively maintained at the moment.

PS: The default--it knows how to produce .ps and .eps files, which can
be converted into PNG or PDF.

TeX: Produces a TeX file of one sort or another, which can then be
converted into all the things the PostScript can be converted to.  A
bit confusingly, the TeX backend actually uses a good bit of
PostScript directly, because TeX is no good at drawing things.

SVG: Produces an SVG (scalable vector graphics) file.

scm/stream: Mostly useful for developers -- dumps out the Scheme code
LilyPond would normally have used to produce output.

David