PDA

View Full Version : Lightwave too slow?



AmigaNewTek
06-01-2011, 03:39 AM
Trying to create a snow storm, but i have some difficulties with particles rendering.

First, particles are too little compared to the scene. If i want to put many particles and make them visible in the scene, i have to increase their size. Rendering, calculations, drawing operations are too slow. I noticed that calculations and geometry visualizations are really too slow. Multicore in calculation in not suppported and GPU is not used. As soon as the scene become complex, all lightwave becomes slow. Interface seems to be slow as well. What can i do to accelerate all drawing, calculations and rendering operation?

wibly wobly
06-01-2011, 05:28 AM
is it mainly the rendering speed you're having issues with or is it the sheer amount of particles you have in the shot? if it's rendering really slow, are you using hypervoxels or the new pixie dust? you can always run to AE if you need snow. there's a somewhat cheesy snow generator that comes with AE that might do what you need and it's a lot faster then 3Ding it.

I wish they're enable multi core calculations for dynamics as well. it would really speed things up but, with core and bullet physics coming around at some point, I don't know if it's worth it now.

AmigaNewTek
06-01-2011, 05:59 AM
is it mainly the rendering speed you're having issues with or is it the sheer amount of particles you have in the shot? if it's rendering really slow, are you using hypervoxels or the new pixie dust? you can always run to AE if you need snow. there's a somewhat cheesy snow generator that comes with AE that might do what you need and it's a lot faster then 3Ding it.

I wish they're enable multi core calculations for dynamics as well. it would really speed things up but, with core and bullet physics coming around at some point, I don't know if it's worth it now.

Rendering is slow when you use Hypervoxel, particle bur, motion blur, and other things. Dunno know what pixie dust is. It's time to get hw acceleration on the entire Lightwave pipeline, isn't it?

MUCUS
06-01-2011, 06:07 AM
Don't think that LW renderer is slow compare to other, so when I'm running out of resources, I try other things: motion blur and particles blur in post, choose sprite instead of volume in hypervoxel (particularly for snow, it could really do the tric and save a lot of time)

And excuse me, but isn't multi core dynamics computing a feature which have been integrated with 9.6 ? (Oooh damn I'm pretty sure that french cows write English better than I!)

That's say, yes, we all are praying for the new Core to come and spread magic all over our pipeline :)

wibly wobly
06-01-2011, 07:46 AM
pixie dust is avail in the HV setting window. setup is similar to using HV rendering but, it's a lot faster. keep in mind that rendering something like this in 3D is probably always going to be slower then doing it in AE or equivalent due to the kind of calculations it needs to do. you have a boat load of control but, you pay for it in output speed imo.


And excuse me, but isn't multi core dynamics computing a feature which have been integrated with 9.6 ? (Oooh damn I'm pretty sure that french cows write English better than I!)

I've never seen it. Everytime I do any dynamics calculations, I only have one core running. It's been like that as far back as I can remember since I started using multi core / multi processor machines.

dwburman
06-01-2011, 09:12 AM
Actually, Pixie Dust is added via the Add Volumetrics drop down menu in the Volumetrics & Fog Effects panel.

AmigaNewTek
06-03-2011, 02:17 AM
Don't think that LW renderer is slow compare to other, so when I'm running out of resources, I try other things: motion blur and particles blur in post, choose sprite instead of volume in hypervoxel (particularly for snow, it could really do the tric and save a lot of time)

And excuse me, but isn't multi core dynamics computing a feature which have been integrated with 9.6 ? (Oooh damn I'm pretty sure that french cows write English better than I!)

That's say, yes, we all are praying for the new Core to come and spread magic all over our pipeline :)

Used sprite, but still slow. Can't have decent result, especially if i use this settings found on the tutorial: http://www.3dluvr.com/content/article/106/2

100000 particles make the system very slow if you add opther things or volumetrics. Calculations are done with one processor only, used @ 25-28% in my system. I would like to find the scene file of the tutorial above to see if i've done something wrong.

wibly wobly
06-03-2011, 05:15 AM
Post your scene and tell us in detail what you're trying to do.

prometheus
06-03-2011, 09:48 AM
perhaps you could try and setup several particle emitters with an offset in depth of the scene, and use less particles, maybe 50 000 on each, but only simulate one at the time, if you have maybe three or four such emitters you should render them out individually in passes and then comp them and correct in after effect or fusion.

A small amount of animated textured environments might work to depending on skills setting it up.
You could also mix your heavy particle amount with a very few particles with big particle sizes and some hypertextures effects, I would recomend HV sprites, or pixie dust for all this particle stuff.

another option is to use fog with activated backdrop color, and use animated textured environment for getting more depth to the textured environment.

and lastly..take a look at turbulence fluids, Itīs not only for fire and smoke, It could very well work great for a snowstorm, In fact I believe It would yield the most realistic snowstorm apart from shooting a real life one.

Michael
http://vimeo.com/user680656/videos/sort:plays

dwburman
06-04-2011, 08:32 PM
You could make an emitter with fewer particles, calculate the snow falling and save the resulting calculation. Then clone or add more emitters in different positions, load the saved .pfx file and offset the time on each of the new emitters. That way you can have millions of particles, but you only need to calculate tens of thousands of them.

XswampyX
06-05-2011, 07:14 AM
You could try making your snow emitter denser towards the camera.

http://i465.photobucket.com/albums/rr16/xXswampyXx/SnowEmitter.jpg

Also it seems quicker if you set up your particles with say 100 in number per frame, then calculate, then put it up to 10000 per frame.

I don't know why...

http://i465.photobucket.com/albums/rr16/xXswampyXx/SnowTest_rgb0600.jpg

AmigaNewTek
06-06-2011, 05:39 AM
Post your scene and tell us in detail what you're trying to do.

Well, my scene is not an example of the lightwave best practices, cause i'm only a passionate spare time user. Btw, i'm trying to simulate a space ship landing on frozen planet during a violent snow storm.

AmigaNewTek
06-06-2011, 05:45 AM
You could make an emitter with fewer particles, calculate the snow falling and save the resulting calculation. Then clone or add more emitters in different positions, load the saved .pfx file and offset the time on each of the new emitters. That way you can have millions of particles, but you only need to calculate tens of thousands of them.

Interesting. I will try your suggestions. Actually the whole scene is slow, not only the calculations. Even move or adjust geometry is very very slow. I have a quad core system with 4 gb ram and 512 MB Nvidia 8800. Geometry acceleration in Lightwave is not used, i guess. When i hit "calculate" only one processor is used @ 25-28%. I tried on different systems with same results.

AmigaNewTek
06-06-2011, 05:50 AM
You could try making your snow emitter denser towards the camera.



Also it seems quicker if you set up your particles with say 100 in number per frame, then calculate, then put it up to 10000 per frame.

I don't know why...



How can i make the particles denser toward the camera? I was thinking about something similar, but i don't know all the lightwave features. Just thinking about if the size of the scene can make all things slower. It's different to use a 10k land, 400 m land or 100k land size? In that case i have to reduce all the object proportions or what?

Thank you all for the kind reply

wibly wobly
06-06-2011, 10:14 AM
Well, my scene is not an example of the lightwave best practices, cause i'm only a passionate spare time user.

It doesn't matter to me how good or bad you think it might be, if I can lend a hand somehow, it's all good to me.


Btw, i'm trying to simulate a space ship landing on frozen planet during a violent snow storm.

Changing the camera's lens to get more or less depth of field in your shot might get you the effect you're looking for.

Just a side thought, what opengl mode are you running in? Multitextures or GLSL shaders? If it's the latter, that could very well be killing your viewport speed.

XswampyX
06-06-2011, 05:05 PM
Here's the scene...

Select the object >- SnowGround:Layer2 (it's actually the snow emitter).

Then Object Properties.
Then Dynamics.
Click on FX Emitter.
Set Birth rate to 20.
Click Calculate.

Wait 20 Seconds.

Change birth rate to 1000.
DON'T CLICK ON CALCULATE!
Just scrub the bar through the animation.

Tada! Lots of lovely particles... I got it up to Birth rate 20,000 before it went clunky on me. That's 800,000 for the scene.

Cheers!

AmigaNewTek
06-07-2011, 03:38 AM
Here's the scene...

Select the object >- SnowGround:Layer2 (it's actually the snow emitter).

Then Object Properties.
Then Dynamics.
Click on FX Emitter.
Set Birth rate to 20.
Click Calculate.

Wait 20 Seconds.

Change birth rate to 1000.
DON'T CLICK ON CALCULATE!
Just scrub the bar through the animation.

Tada! Lots of lovely particles... I got it up to Birth rate 20,000 before it went clunky on me. That's 800,000 for the scene.

Cheers!

Thank you for the scene. I will study whole scene and settings accurately.
However, i've managed to improve the speed of rendering, at least. Removed unused layers of Starball created in layout. These layers where not used, but it's seem that where able to slowdown the entire rendering process and other things. Need to gain speed on calculations using your suggestions. Thank you.

rapscallion
06-08-2011, 03:36 PM
There are a few simple things you can check on any lws file before rendering to save time.

For example, check the subdivision level for every item - even on nulls and particle emitters. Even though they are not geometry based, Layout will assign a generic number '3' to the subpatch setting. During the render, lwsn will see this number and check it. It won't eat huge amounts of time, but in a very complex scenes with tons of nulls, it will be forced to check each object regardless. This goes for geometry based objects that are not subpatched, as well; even though it is not a subd object, layout will assign a subd setting and lwsn will be forced to review the object before it starts drawing the frame.

You can also trim time off the lwsn render by making sure that you exclude null items from the 'object' list of any given light. Sure, nulls cannot be seen - but lwsn will take a tiny moment to consider anything in the 'object' list unless it has been excluded. There are plugins that will allow you to set light exclusions for all objects and lights at once, so it just takes a minute or less to final prep any scene.

Another thing to look at is your render globals panel. Every item that is checked but not actually needed to achieve your result will take time during the calculation. For example, don't have 'Ray Trace Refraction' active unless you have an item in your scene using a texture that would call for refraction to look correct. Same with 'Lens Flares', 'Volumetric Lights', etc. The time lwsn will eat in reviewing these settings is small, but if your scene has alot of frames, it could really add up over time when facing a deadline.

Regarding particles specifically, you should have multiple emitters that are set-up relative to your camera settings. Detail level and overall number of the particles should be reduced the further items are from camera - especially if you are using DOF or planning to add DOF in post. Additionally, HV particles always take longer to render when they are part of a scene with geometry and backdrops. For example, let's say you have a full environment laid out which can render without particles at a time of Xseconds/frame. Then you add the particles and it takes Xseconds+Yseconds/frame. But, if you were to render the particles in a separate lws file using 'matte' objects to replace the environment pieces, you might find that Y is shortened by anywhere from 10% to 50% or possibly even more. If you are rendering a single frame, this doesn't matter too much - but if you are rendering a long sequence with many frames, it will add up to a big savings in the long run to render those particles in their own lws and composite them in post. Additionally, by compositing in post, you have additional control over the final appearance of the particles without worrying about messing up the base image.

AmigaNewTek
06-09-2011, 02:54 AM
There are a few simple things you can check on any lws file before rendering to save time.

For example, check the subdivision level for every item - even on nulls and particle emitters. Even though they are not geometry based, Layout will assign a generic number '3' to the subpatch setting. During the render, lwsn will see this number and check it. It won't eat huge amounts of time, but in a very complex scenes with tons of nulls, it will be forced to check each object regardless. This goes for geometry based objects that are not subpatched, as well; even though it is not a subd object, layout will assign a subd setting and lwsn will be forced to review the object before it starts drawing the frame.

You can also trim time off the lwsn render by making sure that you exclude null items from the 'object' list of any given light. Sure, nulls cannot be seen - but lwsn will take a tiny moment to consider anything in the 'object' list unless it has been excluded. There are plugins that will allow you to set light exclusions for all objects and lights at once, so it just takes a minute or less to final prep any scene.

Another thing to look at is your render globals panel. Every item that is checked but not actually needed to achieve your result will take time during the calculation. For example, don't have 'Ray Trace Refraction' active unless you have an item in your scene using a texture that would call for refraction to look correct. Same with 'Lens Flares', 'Volumetric Lights', etc. The time lwsn will eat in reviewing these settings is small, but if your scene has alot of frames, it could really add up over time when facing a deadline.

Regarding particles specifically, you should have multiple emitters that are set-up relative to your camera settings. Detail level and overall number of the particles should be reduced the further items are from camera - especially if you are using DOF or planning to add DOF in post. Additionally, HV particles always take longer to render when they are part of a scene with geometry and backdrops. For example, let's say you have a full environment laid out which can render without particles at a time of Xseconds/frame. Then you add the particles and it takes Xseconds+Yseconds/frame. But, if you were to render the particles in a separate lws file using 'matte' objects to replace the environment pieces, you might find that Y is shortened by anywhere from 10% to 50% or possibly even more. If you are rendering a single frame, this doesn't matter too much - but if you are rendering a long sequence with many frames, it will add up to a big savings in the long run to render those particles in their own lws and composite them in post. Additionally, by compositing in post, you have additional control over the final appearance of the particles without worrying about messing up the base image.

Thank you for the informations