Node: On EPS previews, Next: Misplaced previews, Previous: The Emacs interface, Up: For advanced users
preview-image-type
preview-image-creators
preview-image-type
. What to do for each of the various settings,
what options to pass into GhostScript, and what Emacs image type to use
is specified in preview-image-creators
. The setting
postscript
is not offered when customizing
preview-image-type
since it is mostly of historic interest and
will not work satisfactorily. preview-image-type
defaults to
png
. For this to work, your version of GhostScript needs to
support the png16m
device. If you are experiencing problems
here, you might want to reconfigure preview-image-creators
or
preview-image-type
.
Most devices make preview-latex start up a single GhostScript process
for the entire preview run (as opposed to one per image) and feed it
either sections of a single PostScript file or separate EPS
files in sequence for conversion into PNG format which can be
displayed much faster by Emacs. Actually, not in sequence but backwards
since you are most likely editing at the end of the document. And as an
added convenience, any preview that happens to be on-screen is given
higher priority so that preview-latex will first cater for the images
that are displayed. There are various options customizable concerning
aspects of that operation, see the customization group Preview Gs
for this.
preview-gs-options
-dTextAlphaBits=4
and
-dGraphicsAlphaBits=4
. Decreasing those values to 2 or 1
might increase GhostScript's performance if you find it lacking.
Running and feeding GhostScript from preview-latex happens asynchronously again: you can resume editing while the images arrive. While those pretty pictures filling in the blanks on screen tend to make one marvel instead of work, rendering the non-displayed images afterwards will not take away your attention and will eventually guarantee that jumping around in the document will encounter only prerendered images.