RE: [XaraXtreme-dev] Re: Filter IDs (was Re: FW: [Bug 1294] New: Problems with "save as" in version 1475)

["Gerry Iles" <GerryI@xxxxxxxx>]

The export hint was a special record that was added so that
"recommended" export settings could be saved in a Xar file for when it
was used in Webstyle or in the online graphic makers.  I've had a look
and it has no bearing on this at all...

I'm not certain but I presume the PNG filter (and presumably GIF and
JPEG) uses those values so that all the bitmap based filters were
consistent in some way.  It looks like something to do with the way the
bitmap export options are defined and passed back and forth to the
options dialog but it doesn't seem to make much sense to me.  I suspect
it may be a relic that should have been eliminated when the original
bitmap export options system was changed to have the comparative preview
dialog for some of the filters.  Transparent and interlaced are both
boolean options and treating them as four distinct bitmap types isn't
very sensible.  E.g. if the user selects export bitmap, chooses GIF,
selects interlaced and then changes to PNG I would expect that
interlaced would still be selected.  Xtreme currently doesn't do this
(e.g. when you select PNG the interlace switch is cleared) and this is
almost certainly because of this weird filter type conversion that gets
done.

I think implementing the new bitmap export preview dialog should also
include a general tidy up of the bitmap side of the filter system.  This
would involve moving more of the export options into the base class so
they can be preserved when the filter is changed (e.g. all options that
are valid for more than one filter should be in the base class) and
allowing a filter to add its own filetype specific options to a derived
options class and to add UI for modifying them to the export preview
dialog.

Gerry

-----Original Message-----
From: owner-dev@xxxxxxxxxxxxxxxx [mailto:owner-dev@xxxxxxxxxxxxxxxx] On
Behalf Of Alex Bligh
Sent: 19 July 2006 13:05
To: dev@xxxxxxxxxxxxxx
Cc: Alex Bligh
Subject: Re: [XaraXtreme-dev] Re: Filter IDs (was Re: FW: [Bug 1294]
New: Problems with "save as" in version 1475)

Gerry,

> BTW: The export hint uses its own enum to store the filter type.  Only
> some filters cause an export hint to be saved (jpeg, gif and png) as
> this was added specifically for when files are rendered from templates
> (e.g. in Webstyle and online stuff).

I'm not sure what an export hint is, but the PNG filter was using the
filter_types enum to store transparency and interlace settings.
Is that what you mean?

Alex