[Pmwiki-users] Working with illustrations -- experience using PmWiki

[Joachim Durchholz]

chr at home.se wrote:
> 
> For instance, imagine a directive
> 
> [[sketch:flying-car source=flying-car.dia image=flying-car.png]]
> 
> where I just invented the syntax without thinking it through..
> 
> This could render as several parts:
> * An image (flying-car.png) is shown
 > * A download link for the source of the image
> * An upload link that lets you upload source and image in one go
>   (preferably without having to specify their names)
> 
> If we could get drag and drap to somehow work with this it would be
> even better of course.

This is impossible unless you use JavaScript (which I'd advocate
against, at least one in every batch of security advisories says
"workaround: disable JavaScript").

Even with JavaScript, it would require user-side installation steps, if
only to determine which picture editing program should be used on his
side (fallbacks would be MS Paint on Windows, gimp on Linux... or
"nothing" on Linux if gimp isn't installed... the JavaScript code is
most likely going to be *very* complicated and OS-specific).


Simple HTML is "almost there" though. Downloading a picture is easy
(right-click the image and say "save image as" on most browsers),
uploading would be an upload-and-replace facility. (Just make sure that
uploaded files are subjected to revision control, and get rolled back
together with the Wiki text...)

> It might also be useful to support that the image shown on the wiki
> page is a small version of the image, and clicking on the image shows
> you the big version.

That would be a "thumbnailize" option on the edit/upload page (maybe
with a text field for the thumbnail size). Not sure how to do that well
though - different pages would have different requirements: some would
want the full image page generated automatically, others would want to
manually edit/update the full image pages, yet others might want to add
the image to an existing page.

The generation of the thumbnail could be done on the server side, using
ImageMagick.

> As for the file format that is used for the image of the drawing, I
> think it would be enough if we only supported 'png'.

That's probably an unnecessary restriction. ImageMagic can handle
anything that you might want to see on a WWW page, and newer versions
even have GIF support added back in (the GIF patents just ran out, so
it's legal to support GIF without paying licenses).

Regards,
Jo