Preston Lee's Blog

Tag: javascript

  • Pairwise Sequence Alignment In JavaScript

    I just implemented a sample pairwise sequence aligner in JavaScript for a course. You can demo it at http://alignment.prestonlee.com, and grab the source code under an Apache 2 license at https://github.com/preston/alignment.

  • Debugging JavaScript With Safari

    I usually use FireBug and other FireFox-based tools for troubleshooting JavaScript issues, but never found a solid way to approach it in Safari, my primary browser. It turns out that the nightly builds of WebKit (Safari’s core) also come with a great utility called Drosera.app, which allows you to attach to a running WebKit process and get funky with a JavaScript console.

    w00t l00ps! drosera.png

  • Rails attachment_fu/Kropper Scaling Fix: attachment_fu_skip_resize

    I recently integrated Kropper into a custom RoR application for OpenRain affiliate img surf. A fundamental flaw in the upload-save-crop-save process used by Kropper is that attachment_fu automatically scales down the image on first save to :resize_to dimensions. After the subsequent crop–which may result in a significant drop in resolution–the image is scaled back up to :resize_to dimensions: an ugly lossy operation.

    The attachment_fu_skip_resize plugin gives attachment_fu the ability to temporarily bypass resizing of the full-size original image, thus allowing your final cropped photos to be of the highest quality as possible.

    1. Install the plugin.
    2. In your attachment_fu image class, add.. 
      attr_accessor :skip_resize
    3. Any time you want to save an image without invoking resizing on the original image.. 
      image.skip_resize = true
image.save

      Thumbnails will be generated at their defined resolutions regardless of the skip_resize flag.