I’m running an XParticles 2.5 simulation with 2-3 million particles - and when I ask Krakatoa to do particle repopulation, even with really small figures (and zero subdivision) I’m getting horrendous ‘Rendering Shadow Maps’ and ‘Preparing Simulation Frame’ times. 10, 15, 20 mins and more. Is this normal?
Are there any tricks to speed it up? I’m running XP from a cached file.
Please note that SMALL figures for Fill Radius in Repopulation mean MORE particles!
The Fill Radius value affects the grid spacing you are requesting. If you specify 2cm, a grid with voxels with a side of 2cm will be generated around the original particles, and then one (by default) particle will be put in each voxel. If you would enter 0.2cm, you would be asking for 0.2x0.2x0.2cm voxels to repopulate the same particle cloud. If your X-P particles are closer than that to each other, chances are the cloud and the voxel grid to enclose it would have approximately the same shape, but the grid itself will have now 100x100x100 times MORE voxels, because we reduced the size of the voxel from 2 to 0.2, and where we used to get one new particle we are now asking for 1,000,000 (one million!)
Try INCREASING the Radius and watch the Script>Console for the Krakatoa log. It shows how many particles you have requested. Start with a large Fill Radius and see how many particles you are getting. If the result is not good, reduce the Fill Radius by half and try again (the particle count should go up about 8 times, because reducing by half is the same as one subdivision - a single voxel turns into 2x2x2 = 8 smaller voxels). Keep on reducing until you like the count and the look…
At some point, once you like the shape of the resulting cloud but want more particles in it, increase the subdivisions and/or the particles per subdivision to add more particles to the same grid.
Here is the Repopulation tutorial in case you have missed it:
thinkboxsoftware.com/kc4d-repopulation/
And keep in mind that using the X-Particles cache doesnt save much time compared to actual prt saved caches.
You will still get long preparing times when jumping around in the timeline and rendering X-Particles caches (this is X-Particles related)
Check the log and the time until the repopulation grid actually starts getting calculated.
Ah right. Yes, that makes sense. Will try again tomorrow with some new values!