rautars
commented
7 years ago Due some reason particle creation is very expensive operation on minetest. Last time I checked creating single particle (e.g. drop/snowflake) is more expensive than coordinate/envinronment checks combine.
Still on local mashine (Linux/intelHD) rain/show is around 58fps. view range and shaders should not inpact weather performance because range where particles spawns is fixed. I also not sure if there any shader which applies to particles.
Sometimes fps drasticly drops on minetest depends from blocks around you even when no extra mods mods enebled (outside of default).
I understand that there is performance drop. From forum someone expierence ~18% another does not see drop at all. Its all depends how well default particle number is handled. As particle number is major performance factor when talking about this mod. Its shame that only handful number of particle could be used at the time making raining and snow quite booring.
As for performance testing I suggest edit weather mod e.g. rain.lua particles_count parameter and see how much weather particles can handle your pc and wich number is "ok" (~60fps).
Fixer-007
I did some fast performance testing on this with v_range 160 in a big forest and shaders on (PR4530 fps boost PR was also applied). ATI HD6870 1GB
Results: no weather - >80 fps rain - 55 fps snow - 44 fps
It seems that impact is pretty big, weather halves your fps, this can be slow for people. Needs more optimisations, maybe in engine or irrlicht.