After playing with particles that had been assigned particle images, I noticed in-game that the bottom and right margins sometimes contained noise. Since I was using 24x24 images (same as "leaf" in default ToME) and these margins seemed to be about a fourth of the size of the texture, I figured it might be an issue with the texture size provided. Since changing these textures to powers of 2, I haven't seen the problems again. This problem was intermittent-- sometimes there'd be a margin, sometimes there wouldn't be, and I couldn't figure out what, if anything, was changing to make the noisy margins appear.
I am using an nVidia GeForce 8800 GT, which might be relevant. There is at least one particle image in default ToME with dimensions that aren't powers of 2.
EDIT: I should qualify that this is little more than a suspicion, and iffy hardware may be at fault. My computer is old and does act funny sometimes
