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smmurph
05-31-2007, 09:42 PM
I am fairly new to Lightwave and am doing a 3D model of a new church for the Pastor so he can present it to the county when he goes to ask for building permits. Here is my problem: I am using a bunch of trees that I exported from Vue, and my schene has a total of 2,526,918 polys. The problem is that no matter where I place my camera I have the same number of polys according to the Render Status dialog. It looks like it is also rendering all the pixels in my entire scene every time I attempt a render. Is this true? If so, how do I get it to render just the ones that are in my camera view. I need multiple renders and 8-9 hours per render is just too much!

Any help making a faster render and still having decent scenes would be appreciated. I would also like to do a fly through, however I don't have 6 months to wait for a final render.

Thanks,
Smmurh

smmurph
05-31-2007, 09:53 PM
Another question ... how do I do a realistic area light without casting multiple shadows? I am trying to do fill lights to make up for dark places but I am getting shadows .. strange that lights would cast shadows, huh??

Thanks,
Smmurph

hrgiger
05-31-2007, 10:01 PM
No matter where you place your camera, your scene will always have the same amount of polygons.

Why is it strange that lights cause shadows? If you don't want your fill lights to cast shadows, simply uncheck the cast shadows box in the lights properties panel.

There's too many variables here to tell you how to get a decent faster render. You have to give more details. Which version of Lightwave are you using? Do you have Fprime? What settings do you have in your render panel as far as raytracing goes? How many lights? Which camera type? Stuff like that.

JamesCurtis
05-31-2007, 10:01 PM
LW will render all polys and pixels within the camera view unless you set up a Limited Region for rendering. Refer to the LW manual for more info on doing this.

As far as your imported Vue trees, they are very heavy in polygons. You might get better polygon/rendertime results if you save out a render of only your individual trees [nothing else] in Vue with a solid white background and then use the resulting image [one with an alpha channel preferably] mapped to flat plane 4 point poly rectangles created in LW Modeler and sized to match the tree images from Vue.

The other option is to take the trees into Modeler and use a plugin such as Reduce Polys, Reduce Poly's +, or QEMLOSS. First two should be part of LW Modeler. For the last one just do a search on www.Flay.com for it.

Hope I've helped.

smmurph
05-31-2007, 11:08 PM
Thank you both. I have a long way to go before I am proficient at LW. Am using LW9 and love it. Have had LW since 6.5 but am just now really getting into it! I got rid of some extra trees and turned off the shadows on 3 of my 4 lights and voila ... my 9 hour render became a 2 1/2 hour render. Still not good enough for a fly through, but I will keep tweaking.

As soon as I get this render done I will check my other settings. I know I am using the regular cam, radiosity, rendering at medium in anti-aliasing, and I didn't apply anything to my surfaces except color or image maps (didn't tweak the luminosity, et. al.). I am rendering right now so I don't want to stop to check my settings.

The scene I am rendering has an orchard behind it so I still have 2 rows of trees ... they are fairly low poly according to Vue, however when you have 20 of them it adds up. Isn't there a function that makes geometry much smaller shwn farther away and only renders full geometry when close .. .I can't think of what it is but it would probably help when I do my fly through ...

I know Noobs are annoying, but I appreciate any help I can get. And thanks again for the above answers.

Smmurph

AbnRanger
06-01-2007, 01:27 AM
Thank you both. I have a long way to go before I am proficient at LW. Am using LW9 and love it. Have had LW since 6.5 but am just now really getting into it! I got rid of some extra trees and turned off the shadows on 3 of my 4 lights and voila ... my 9 hour render became a 2 1/2 hour render. Still not good enough for a fly through, but I will keep tweaking.

As soon as I get this render done I will check my other settings. I know I am using the regular cam, radiosity, rendering at medium in anti-aliasing, and I didn't apply anything to my surfaces except color or image maps (didn't tweak the luminosity, et. al.). I am rendering right now so I don't want to stop to check my settings.

The scene I am rendering has an orchard behind it so I still have 2 rows of trees ... they are fairly low poly according to Vue, however when you have 20 of them it adds up. Isn't there a function that makes geometry much smaller shwn farther away and only renders full geometry when close .. .I can't think of what it is but it would probably help when I do my fly through ...

I know Noobs are annoying, but I appreciate any help I can get. And thanks again for the above answers.

SmmurphAPS...Adaptive Pixel Subdivision. You can browse the video tutorial on this site to see how it works:
http://www.newtek.com/lightwave/videos.php

If you have the building UV Mapped, you can simply export it into Vue, and render the scene there (since it handles those high poly counts MUCH better than a traditional program like LW). I wouldn't use Radiosity, considering you circumstances...either in LW or Vue. Global Illumination at a low-medium value would bring those render times down and give you a similar look. Or shave them even further by not using Radiosity or GI, just regular raytracing, and use fill lights set at low intensity levels to fake GI or Radiosity.
Have you downloaded the free update to 9.2? They worked heavily on improving GI and Radiosity... so before you ditch them altogether, you may give it a test to see if they are within acceptable limits.

One other thing. FPrime has fast Radiosity. Ask your Pastor if they can help you foot the cost. No more multiple test renders. It updates instantly as you work, and is a very fast (full...not just preview) renderer. Not sure if you already knew this, but given your difficulty, FPrime would be one of the first places to look for help.