Archive for December, 2009

I've been spending my project time learning how to manipulate images in PHP to let me create custom growth charts and the like, with a RESTful interface that would allow them to be used as the source of <img> elements. I like the way things turned out; they are available at It includes height,weight, head circumference, peak expiratory flow (for managing asthma), blood pressure and bilirubin levels. While it took a fair amount of trial-and-error to get things to work, I don't think there's much that's innovative enough programming-wise to write a tutorial.

I want to get it to parse the Accept: header, so users can leave out the file extensions, but it looks like browsers don't implement that correctly, so I'll have to keep using extensions as well.

I still need to learn more about caching and effectively using eTags and all the headers that go with it. It always makes my brain hurt.