Fix random artifacting on nyanalyzer on startup

memset works on bytes, not the source datatype width

...unless getting NaNs in the paths are related to <i>NyaN</i> cat...
![screenshot from 2014-05-21 233002](https://cloud.githubusercontent.com/assets/4623333/3066056/abd5bcb0-e26c-11e3-9973-22f000d6af7c.png)