Posts in August, 2008

A Python Challenge. Better than rentacoder?

Python programmers love a challenge, so I thought I would throw this one to the lazyweb.

I have an app that generates a large sequence of files, the nature of which is unimportant. What is important is generating a location to store them. To keep the directory structure manageable there should be no more than 100 files plus sub-directories in any given directory. For instance if there are 99 files in a directory, then there is only room for one more file or a directory -- bringing the total to 100. There is an additional requirement that the directory structures should be as flat as possible, i.e. foo/bar for the nth item is preferable over foo/bar/baz. To summarize the requirements: continue reading…

Charting my progress

I spent another afternoon working on my pie chart project. I'm using PyCairo to render labels over the chart render. The tricky part was finding the position at the center of each pie segment to render the label over. There's no way of retrieving that information from Povray, so I had to do the math myself and calculate the coordinates manually. Fortunately I had a 3D math module that I was intimately familiar with, having written it just last year (its always gratifying to re-use code for a new purpose)!

Small div bug in Firefox?

When writing the image wrapping script, I came across a difference between Firefox and Opera. Basically, when there are small floated divs in a vertical stack, the text to the right will be aligned to the topmost div in Firefox, even if the divs underneath extend farther than the topmost div. Opera handles this situation better and places the text after the maximum extents of the floated divs. Take the following HTML:

<div style="float:left;clear:left;width:100;height:8px;background-color:#55f;" ></div>

<div style="float:left;clear:left;width:120;height:8px;background-color:#66f;" ></div>

<div style="float:left;clear:left;width:140;height:8px;background-color:#77f;" ></div>

<div style="float:left;clear:left;width:160;height:8px;background-color:#88f;" ></div> continue reading…

Image wrapping script

After posting my latest pie chart image, it occurred to me that it would be pretty cool if the text flowed around the edge of the pie chart image rather than around a rectangle. This is not something that can be done simply with HTML / CSS, but it can be done by breaking the images up in to horizontal slices so that they extend only to the edge of the image, rather than to the absolute border.

If I googled for it, I suspect I could find tools to do this for me -- but where is the fun in that? Instead, I wrote a Python script that uses the Python Image Library to scan an image and output HTML that will allow text to wrap smoothing around the image. No additional images are produced, because the 'slicing' is done with CSS to select the part of the original image that is seen. continue reading…

More Pie?

I've been doing a little more work on my 3D pie-chart renderer. I've added beveling and tweaked colors to a point where I can render charts that -- in my opinion -- are a better quality than those produced from Apple's Numbers. Next step is to add labels over the main image. Povray does support rendering of True Type Fonts, but it is a 2D overlay that I'm looking for (not 3D text), so I plan to use PyCairo to render the labels. Once I've perfected the chart renderer I can build a polished web interface, and a web service for the render queue. All in Python, of course!