"Scratch your own itch" is one of the mottos of the open-source movement. And this evening, I had one monstrous itch.

If you saw this blog more than a week ago, you'll remember that I only recently cleaned it up from a horrible mess and upgraded it to Drupal 6 at the same time. Since then, I've found numerous small ways to improve it. For the most part I use widely available addons (archive, tagadelic, adsense, agregado), but I freely hack away at them when I need more functionality.

For example, you may notice that when you are on an older post from October 2007, the calendar block to the right will show October 2007 instead of November 2008 - it doesn't do that out of the box. The tag cloud shows tags from both vocabularies, both the freely tagged "keywords" and the strictly hierarchical "news category", which required some extra code as well.

{{image_flow.png|right|200px}}But to get back to the itch above, I was really annoyed with the poor image attachment support. I can attach image files to every post, but they will be displayed below the text - to add them in the text itself, I have to enter specific HTML after I've uploaded the images, and this HTML will break if the site ever moves anywhere else, since it references internal paths.

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What I started out with was a contemplate template that was intended to replace internal placeholders like the below (wiki-like syntax) with appropriate HTML to add the image in a floating box.

{{image.jpg|right|100px}}

Then I realized that I wanted to generate thumbnails server-side, and the template very soon spilled over into its own module. And so I can now, after an evening of coding, present Image Flow.

{{druplicon.small_.png|left|100px|noresize}}Image Flow hooks in at the "alter" (final) stage of hook_nodeapi. It checks your node for the content of CCK imagefield fields, then scans for placeholders like the above to replace them. Images get automatically scaled to the proper dimensions, and added as a floating box on the proper side within the text.

Then - and this is what I'm most proud of - the full-size image can be viewed in a box that fades in when you click on the thumbnail, Lightbox-like.

Image Flow is barely ready for testing, let alone release, but a version for Drupal 6 has been attached to this post. You can also check it out from my SVN repository:

svn co http://svn.ermarian.net/drupal/modules/image_flow

If you do not want an image to be enlargeable (for example, a software logo that offers no additional information in full size), the extra option "noresize" will cause the thumbnail to be shown without any full-size link.