Okay I fixed the problems particles were having with draw distance. It turned out there was a weird line in there resetting their distance to 0 on each frame, and generally the treatment of distance wasn’t very consistent.
Now, it all displays properly, but there’s a bit of a conceptual issue: Basically, if I set it so particles can spawn within the screen width, that means the further-back particles are only there in the square that’s the projection of the screen off into the distance, creating a kind of tunneling effect. However, if I make the effect large enough that the background seems natural, that means there’s a ton of wasted particles in the foreground being drawn outside the boundaries of the screen. I dunno, maybe that’s not a problem, since (because foreground elements move faster) those images could sweep onto and off the screen pretty quickly, but it definitely seems at least a tad sub-optimal. I’ll think about it anyway.
I should admit, over the last few days I’ve been rather distracted by Dark Souls 2, but I figure as long as I make steady progress every day it’s all good. There’ll be slow days and fast days, and better for it to be because of an awesome game than because I just feel shitty. At least the former will pay out in inspiration in the long run.