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View Full Version : some secret to getting HV's to render at half resonable speed?



KillMe
08-22-2005, 04:26 AM
i'm trying to do a scene where a ship is reentering the atmosphere anyway even on the lowest settings for shadows, quality etc etc etc and with afew particles as on screen as i can get away with it is taking an age - tis currently running at 45mins a frame on a dual opteron 248 - thats nto exactly practical - do people who actually use hv's alot all have renderfarms?????????

surely there has to be some way to make them render faster and still not have transparcy issues with the edges of the object thats glowing aroudn teh bottom of the craft?

Mylenium
08-22-2005, 05:07 AM
i'm trying to do a scene where a ship is reentering the atmosphere anyway even on the lowest settings for shadows, quality etc etc etc and with afew particles as on screen as i can get away with it is taking an age - tis currently running at 45mins a frame on a dual opteron 248 - thats nto exactly practical - do people who actually use hv's alot all have renderfarms?????????

surely there has to be some way to make them render faster and still not have transparcy issues with the edges of the object thats glowing aroudn teh bottom of the craft?

Ahem, the most efficient way is not to use them at all *g*. No, seriously, have you considered compositing? Normally I render my HV's in a separate pass and then bring them together. Unless you need shadows and such on your HV's e.g. like an airpalne casts on clouds (which is unlikely in your case, since it's supposed to be a fiery burst), this works like a charm. It will allow you to independently balance quality and speed without affecting the beauty pass. Also try to use Sprites only whenever you can. The cut down on rendering times is significant and unless you get very close to them, Sprites will in many cases look just like true volumes. Do also not forget mapping techniques on otherwise invisible/ transparent geometry. Watch "Babylon 5" or "Star Trek - Deep space Nine", "Voyager" and "Enterprise" for some inspiratrion on that latter technique.

Mylenium

starbase1
08-22-2005, 05:45 AM
That does seem VERY high, can you be a bit more specific about what you are doing?

One thing you have not mentioned, it can be a big help to get the number of octaves / levels in textures as low as possible...

Nick

KillMe
08-22-2005, 06:06 AM
unfortunatly since switching to x64 DXF+ no longer runs ( no serial x64 dongle drivers for it - used to think i was lucky that i got dxf= with its own dongle but if it was tied to my lightwave dongle it would probally still work ) - trying to think up some solution to this at the moment but in the immediate short term i cant composit them together

i tried it with sprites first but had awful artifacts on the transparent edges ( see images for comparison )

i should probally point out that part fo the problem is that fact i'm wanting motionblur on it - trying to keep the passes down i've got it on 3 passes with dithered motion blur

i'll try dropping the procural octaves in teh hypertexture see if that helps

starbase1
08-22-2005, 06:26 AM
Ah, the image helps. I have found that reducing overlap of HV's has a massive effect on render times. Lots of little ones that barely overlap may well have a much faster render time than a few that overlap a lot.



Nick

KillMe
08-22-2005, 06:31 AM
more particles? kinda weird logic but i'll give it a go =)

KillMe
08-22-2005, 06:46 AM
oh i should also point out that those frames didn't take that long - its as the camera is getting closer to the ship liek thsi one its taking so long

T-Light
08-22-2005, 06:49 AM
KillMe-

unfortunatly since switching to x64 DXF+ no longer runs
OUCH :(

No DFX when you really need it, b*mmer.

Do you have Photoshop or something similar with Macro functions?
Probably teaching a Granny to suck eggs here, but I used to that technique for compositing animation and SFX across hundreds of frames prior to DFX.

papou
08-22-2005, 04:08 PM
hi,
try the trick of the transparency poly in front of camera, it can help to accelerate HV.

hrgiger
08-22-2005, 04:33 PM
The secret to fast HV's. Travel 25 years into the future. Abscond back to present day with a 3000 GHZ computer. HV's should now render in faster then real time.

How to get to the future? I could tell you but you didn't ask for that particular secret.

On a more serious note, are you using volume, sprite, or surface HV's? Volume takes the longest to render and depending on your shot, you might be able to get away with surface or sprites(EDIT: I see after reading your recent post above, you already poo-poo'ed the sprites). Also, the size of the HV's can impact your rendertimes. Decreasing the amount of particles that the HV's are applied to can significantly reduce render times.

You've also seen that the closer the camera gets to the HV's, the longer they take to render. Try pulling back slightly and see if it makes a difference.

KillMe
08-22-2005, 04:44 PM
hmmmmm i'll 50 years in to futue and bring back a 4.2 THz Octacore 128bit quad board but you understand i'm on a budget =)

while i'm at it i'll bring back lightwave 70.5 hmmm could sell it to newtek :thumbsup:

SplineGod
08-22-2005, 05:27 PM
One thing I would do is not use HVs and use geometry with displacements running thru it. After that I would look at using a few particles and HVs. :)

Lito
08-22-2005, 09:00 PM
Just wanted to point out for KillMe that if you go here:
http://www.aladdin.com/support/hasp/enduser.asp

They have the DFX dongle drivers for Win32 and Win64 :)

I don't know if it'll work because I haven't gon to Win64 yet, but I just decided to check because I did buy the separate dongle also.

toby
08-22-2005, 11:11 PM
Sometimes HV renders much faster with 1 thread than multi-threaded, give that a try - you could then render with 2 copies of LW and use both processors more efficiently.

KillMe
08-23-2005, 05:44 AM
yeah tried those drivers no luck must be for usb dongle only or something =/

papou
08-23-2005, 06:42 AM
in fact the transparency poly trick don't help in your case.
it can help only when the rendering of the geometrie take long too. Then the HV can be rendering same times as the geometrie and not in a second long volumetrics pass.

maybe, you want to test JetstreamFX. it's a OpenGl particle renderer so it's extremely fast. realtime in fact.
http://www.dstorm.co.jp/english/products/jstrm/index.htm

toby
08-23-2005, 10:01 PM
d**m cool looking by the way


I can't BELIEVE you can't say ****.
:twak:

Lude
08-24-2005, 01:34 AM
:agree: Man i just tried the demo of JetstreamFX - that's really really cool.

Are there any more plugings like that out there.

krimpr
08-24-2005, 05:51 AM
Probably not exactly what you're looking for but I'm assuming you've already checked out Particle Illusion? I know it's for post but Al Street has a package of scripts to export tracking information out of LW into Particle Illusion for emmiter motion. KillMe's shuttle scene may be tricky, (nice work BTW) but it sure saves rendering cycles big time.

http://www.wondertouch.com/default.asp

starbase1
08-24-2005, 06:09 AM
d**m cool looking by the way

I can't BELIEVE you can't say ****.
:twak:

Yes, that surprised me too! I had to resist the temptation to post a seriously **** message and see which ****ing words the ***ing ***s consider too ***ing **** for use in these ***ing forums. :jester:

mav3rick
08-24-2005, 07:37 AM
funny thing is noone of 3rd party developers offered replacement for hv3... except dstorm but theyr jetstream doesnt do real volumetrix.

Intuition
08-24-2005, 12:29 PM
I've use particles illusion since right before 2.0 came out. They are on v3 now I believe.

JetStream and PI are not real 3d volumetrics but do a nice speedy job of emulating most of the effects. I used to do lens flare sequences in black and white and then apply that image sequence to particles with the sprite filter.

Then set the frame to be the same as the particle age. so on particle brith your on frame 0 and then after 10 frames of life you are on frame 10.

This is how I used to cheat these effects in Lightwave. Make image sequence animations and attach them as sprites. Now PI and Jetstream do similar stuff.

The cool thing about using Lightwaves native sprites with an image sequence is that it renders really fast and it also is seen in the tracer so you get reflections and refractions and the works.