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living3d
07-29-2011, 08:01 PM
Hello,
As you can see from post name I have a huge rendering time. I'm rather new to interior rendering and very upset with my results.

Here is a little test of that scene.

http://img263.imageshack.us/img263/6103/cam1test3.jpg (http://imageshack.us/photo/my-images/263/cam1test3.jpg/)

Uploaded with ImageShack.us (http://imageshack.us)


To light the scene i used Sun&Sky with portal light. All artificial lights are wom_archilights and objectlights. As I'm new to this great wom shaders I thought the problem is there. Rendering is much faster if I hide those lights but still very long...
I render through command line and result is frustrating: FG phase just 13 min, 12 % rendering phase took 6 hours! And this just one FG bounce... :sad:

Here are settings from the scene:
Image resolution - 1200x800
AA: min - 0, max - 2. Contrast - 0,1, Mitchell filtering 4.
Reflection rays - 7, refraction 7, trace depth - 14.
Shadow mode: simple
Primary renderer: scanline
Fg settings: rays - 40, point density - 0,6, interpolation - 40.
Almost all mia materials has glossy reflection and AO with colorbleed.

I switched to Regular BSP and optimized it.
Also was trying to use different memory limit settings, optimizing scene, render in layers, importing into a knew scene with no luck.
System specs: Maya 2012 64bit under Windows 7, Core i5 2.67GHz, 8 GB of RAM.

Is that normal on my system or am I missing something? Thanks for any help.

kiryha
07-29-2011, 08:49 PM
Not sure about rendering time, may be its normal for arch viz, and i never use worm stuff.
But you settings seems to be pretty low. What is raytrace settings(reflect-refract rays) and how many glossy sample you have for each material? AO with colorbleed also make render longer.

living3d
07-29-2011, 09:14 PM
Not sure about rendering time, may be its normal for arch viz...
I want to figure out wether this is optimization problem or normal archviz rendertime.

Thats is the main question that bothers me about my scene.

Yes, my settings are low and I can't allow to set it higher because render will take a week.
Raytrace settings: Refl rays - 7, Refr rays 7
I know that glossy samples are very expensive in terms of rendering so I didn't set it higher than 16.
I've never used interpolations in mia_mat but suppose it can help a bit.
or alot?

kiryha
07-30-2011, 10:18 AM
>Reflection rays - 7, refraction 7, trace depth - 14.
Too high, 2-4-7 would be more than enough(trace dapth= refraction rays+reflection rays+1).
Switch to raytracing, scanline is old stuff.
16 glossy samples is Ok, interpolation will help, especialy with stills it worth to try.
I`m wonder aboun render time for arch too. Waiting what archciz guyes can say.

ytsejam1976
07-30-2011, 11:52 AM
I think the problem are your more furniture object inside the scene and scanline on is deprecable. Use raytracing with bsp2 and try the tests. I think the real problem are the light, for example the object light, maybe they compenetrate some geometry. Try to turn on one light per test and look where the light increse the time. Womarchlight is really good, but need some tweaking on type if candela etc etc etc. On object light try to ins point light. If you have cm2 factor on exposure photo set to 1 try to set it to 3180 and on womarchgliht the photgraphic setting to default maya sun &sky. Aftr this you dont have problem on setting point light intensity to somthing like good, without bigger value.

living3d
07-30-2011, 01:55 PM
>Reflection rays - 7, refraction 7, trace depth - 14.
Too high, 2-4-7 would be more than enough(trace dapth= refraction rays+reflection rays+1).
Switch to raytracing, scanline is old stuff.16 glossy samples is Ok, interpolation will help, especialy with stills it worth to try.

The purpose of setting rays to such values was to let rays penetrate and leave glass of wine geometry that I have on the talbe in front of the camera (That test pretty old and its not seen on that image).I counted that ray should hit surfaces at least six time to leave it. Maybe 6 6 13 is enough.
I will try to check interpolation later because the scene is still rendering.


I think the problem are your more furniture object inside the scene and scanline on is deprecable. Use raytracing with bsp2 and try the tests.

I usually use raytracing and BSP2 when there are many instanced geometry. Btw, the scene counts near 1.5 million triangles. Is that high enough to switch to BSP2?



I think the real problem are the light, for example the object light, maybe they compenetrate some geometry. Try to turn on one light per test and look where the light increse the time.

From the earlier tests, by switching object lights off rendering time was cut significantly. As to objectlight setup, I just copied object which i want to emit light and set up a geo shader and etc.. but it is sit right in that place and penetrates initial object. Maybe this is causing problem.

On object light try to ins point light
What do you mean?

At this moment rendering is still running but tomorrow I'll experiment taking into consideration your tips. Thank you guys. :)

kiryha
07-30-2011, 04:56 PM
Reflection rays =1 mean, that you see reflection
Reflection rays =2 mean, that you see reflection in reflection, enogh for 95% of CG renders.
Reflection rays =6 is wasting of time.

Hamburger
07-31-2011, 03:23 AM
Id've expected something like that to render in around 40 minutes with that res if not faster, definitely not 6 hours for 12%.

I'd say that the wom_archlight is slowing this down, specifically that feature light on the ceiling. If you can just make it glow but not emitt any FG rays it might cut down quite a bit on time. Try and use the least amount of lights in your scene if you want faster times. IES lights are okay if you turn off soft shadowing usually. Hope this can help somewhat.

living3d
07-31-2011, 11:52 PM
Here is image that finally rendered. The original twice as big.

http://img804.imageshack.us/img804/9688/cam1finish.jpg (http://imageshack.us/photo/my-images/804/cam1finish.jpg/)

It took (I'm not kidding) 29 precious hours of my time.. :sad:

I'm trying to follow your tips but I got no essential progress. What I've found that BSP2 is slowing things down. Switching to raytracing and using interpolation could save me a few hours but its unsignificant against the background of almost 2 days. Like you say, the real problem is lighting itself because when I turn on just one objectlight tube rendertime increases in three time. I attempted to set cm2 to 3180 but with no success. Maybe wom lights set up is wrong...

I've uploaded a cleaned up scene in case if someone has little time to look at it.
http://www.megaupload.com/?d=4D2DGGHS

I would really appreciate.

ytsejam1976
08-01-2011, 08:25 AM
In your scene you have a lot of confusing and wrong setup.
Like a say before, the light compenetrated inside the spot and the rays Fg rays casting on the object so set out the light. For decrease you render time after that, set inside the object light node not a womarchlight but a point light, it help more, obviously you don't see the light so increse the v value on color chooser like physical light. You know?
I say you to set the cm2 factor to 3180 for not exagerated increase the V value on color chooser for to see the intensity of the point light, i say MIB_Light_Point.
If you set cm2 factor to 3180, the wom archlight need to set rgb unit to "physical sky/sun maya default"
After that your scene is i don'0t undertsatnd in cm or meter and is difficult for me to run a workflow correctly for resetting your scene.
After that the photographic exposure setting are wrong in all, interior dayl gliht with those setting are unreal. A starting point is: iso 100, shutter 16, focus 8. THis is a starting point.
MIA_PortalLight with 10 of multiplier are wrong, start with 1 mltiplier.
with this setting for an interior daytime render you do all.

Another one:
I don't have your IES Profile so no test are really as your, but try to setup your IES file on your OS HDD?

ytsejam1976
08-01-2011, 11:04 AM
Another one:
:)

Your arealight are to big, this create a lot of shadow rays for areaLight so decrease area light scale to 0.01 if you remain in this unit scale.

Finish. If you are able to purchasing vRay. Buy it. :) and it's says an old Mental ray user.

living3d
08-01-2011, 01:24 PM
First of all thank you for your time. :)


Like a say before, the light compenetrated inside the spot and the rays Fg rays casting on the object so set out the light..

Do you mean objectlight tube penetrating the walls? I've corrected it but rendertime is near the same.


If you set cm2 factor to 3180, the wom archlight need to set rgb unit to "physical sky/sun maya default?
Sorry I don't understand it...you suggest to use mib_light_point with factor 3180 instead of wom_archlight.
When I use mib_light_point seems I can't get realistic glowing surface... On the other side wom_archlight gives very nice glowing tubes...

Would you be so kind to post a simple example (You may use my scene. It is in centimetres)
of physical correct setup wom objectlights with sun&sky. :bowdown:


Finish. If you are able to purchasing vRay. Buy it. :) and it's says an old Mental ray user.
As to vray, maybe it is good alternative to mray but for now i think I'll stay with mental ray because I''ve already got used to it. Got used to it different little issues and difficulties but the result worth it. I believe its like a first and last love :)

ytsejam1976
08-01-2011, 05:47 PM
Yes the object light compenetrated the wall. And i think you don't set the object light good,so i delete the central ceiling object and re create it and render speed more. With your object i have much error on compenetration.

Ok, use wom archlight, but really your scene is not in real unit, maya is set to centimeter but the home is for example the windows is height 2 centimeter son, no rende, not setting are plausible with this situation.

living3d
08-01-2011, 06:04 PM
Ok, use wom archlight, but really your scene is not in real unit, maya is set to centimeter but the home is for example the windows is height 2 centimeter son, no rende, not setting are plausible with this situation.

I always make my scene in cm for the sake of simplicity. Every 1 cm mean 1 meter. 2cm windows = 2meters.


edited

Now I suppose for achieiving physical correctness scene should be in real world units. That is 2cm window should be 200cm?

ytsejam1976
08-01-2011, 06:09 PM
I'm modelling in cm, import or modelling inside maya in cm and set maya in cm, but you always set the other setting in this way, long time and much of the setting not completing good. You know that if you set a 60 watt bulb light in a box of 10 cm you have a bloom and if you set the same light inside a room 500 cm per side you have good light? I thin you know, so if you set the physical: sky&sun, womArchlight, mip_photometric_light or any you want indeed fg scale, you need to set at the same value, so you set it down. It's clarify? :)

living3d
08-01-2011, 06:23 PM
I got what you mean. Thanks for clarifying. :shrug:

InfernalDarkness
08-01-2011, 06:49 PM
It's a nice scene, rather complex lighting too. Even so, it should be rendering in one or maybe three hours, not days... Certainly depends on your specs, but I've done dozens or hundreds of similar scenes for production and believe you me, if my rendertimes took a day, my company would be out of business within a week.

If you disable ALL the lights except the portal light, what are your times like then?

Also, when it comes to raytracing, I always start at 6/6/12 if there's any glass or reflections in the scene. The reason being, reflections also need to be calculated through the (at least) 6 levels of refractions too. Sure, you can get away with less reflection generally, but for interiors with actual physical materials, the difference in rendered results are massively more realistic. And the raytracing overhead is negligible if you're using thresholds anyway, which you should be in the mia_mat_x shaders.

I'll try to check out this scene when I get to my work computer with Maya 2012, perhaps another ideology will help you figure it out.

But is there any reason you're not just using the light_surface shader? Are the womlights and all those other crazy nodes really necessary?

ytsejam1976
08-01-2011, 07:46 PM
I forget the fg settings. You set something like 7-7-? I don't remember. Why?
Set 1-2-3 or 2-2-5 but not 7

living3d
08-01-2011, 09:56 PM
... if my rendertimes took a day, my company would be out of business within a week.
Thats why I decided to have recourse to you :)


If you disable ALL the lights except the portal light, what are your times like then?
I don't remeber exactly but it was much smaller. From the last test with smaller AA settings its 30% of complete time.[/QUOTE]


Also, when it comes to raytracing, I always start at 6/6/12 if there's any glass or reflections in the scene. The reason being, reflections also need to be calculated through the (at least) 6 levels of refractions too. Sure, you can get away with less reflection generally, but for interiors with actual physical materials, the difference in rendered results are massively more realistic. And the raytracing overhead is negligible if you're using thresholds anyway, which you should be in the mia_mat_x shaders.
I agree with you. But in outdoor renderings usually you don't need high numbers because most of the cases objects reflect just environment.



But is there any reason you're not just using the light_surface shader? Are the womlights and all those other crazy nodes really necessary?
I sarted from light_surface materials. But it left a lot of fg artifact (especially in places with thin geometry). I couldn't fully eliminate it even with high fg settings and filter. Then I decided to get acquainted with wom shaders. I was thrilled with it beauty and it was enough to set filter to 1 to get rid of those light spills. Then interior scene was elaborated. After setting AA sampling to 0 2 and hitting render...I was stunned and I'm still because it's just very low fg settings with one diffuse bounce and 0,1 AA contrast.

I forget the fg settings. You set something like 7-7-? I don't remember. Why?
Set 1-2-3 or 2-2-5 but not 7
Because I remdember from some DVD training that it is good idea to set it same as raytracing settings. And you're right by setting it to 2 2 5 its 7% faster without visual difference. Thanks. :)

Still have no noticible improvements... :curious:

InfernalDarkness
08-01-2011, 10:04 PM
I very much concur with your statements. Optimizing a scene is rarely simple, especially in a complex scene, so just keep at it and we'll keep dishing out ideas until we all figure it out with you!

I agree with you. But in outdoor renderings usually you don't need high numbers because most of the cases objects reflect just environment.

Generally this is true I suppose, but regarding trees and leaves and whatnot, I find it best to set the optimizations on a shader level as opposed to a global level, which overrides the global levels per those shape nodes/materials. So that setting "single sample from environment" works better at optimizing a scene's rendertime than changing the global settings, especially for trees and leaves... But that's a digression. I'll try your scene out when I can, soon, and see if I can think of anything helpful.

living3d
08-02-2011, 10:32 AM
...so just keep at it and we'll keep dishing out ideas until we all figure it out with you!
That would be great! :thumbsup:

Another thing that may slow things down apart from incorrect lighting setup is that I'm using memory mapped textures. In maya 2012 I checked auto-conversion. This force mentalray to convert ALL textures. Docs say if your textures are not too large and fit into RAM memory-mapped textures are slightly slower than regular. Right now with auto-conversion flag it consumes 4 Gb (my system has 8 Gb onboard) Don't know...maybe I should convert only big textures with old imf_copy utility. I'll test later after next image complete. :scream:

Bitter
08-02-2011, 06:50 PM
Large textures saved in a caching format are generally more efficient now.

Use imf_copy to save the files as a pyramid filtered exr and it will automatically create a tiled (cached) version with Maya 2012 (assuming Autodesk included the correct imf_copy with the distribution)

imf_copy -p myfile.tif mynewfile.exr

Then be sure the auto-convert is off in Maya.

This should save you some memory and time for large textures because it will call what it needs from the texture instead of trying to eat the whole thing at once.

And like someone else said, remember to turn off Scanline in the render globals (select raytrace as the primary renderer)

living3d
08-03-2011, 07:20 AM
Use imf_copy to save the files as a pyramid filtered exr and it will automatically create a tiled (cached) version with Maya 2012 (assuming Autodesk included the correct imf_copy with the distribution)

Thanks for the info.
Does auto-convert efficient when there are many ONLY large textures in the scene?
What is the difference between .map and .exr conversion?

Bitter
08-03-2011, 05:21 PM
Caching tends to be more efficient than memory mapping, different mechanism. EXR will cache with a native mechanism (tif too but not this version of mental ray I believe)

But if you have the memory it means less. Mipmapping also helps because it might not be necessary to pull a 8k texture when a 2k level will do.

But generally speaking, smaller textures don't benefit very much.

mental ray 3.9 has an improved caching structure that takes advantage of cached textures like EXR.

living3d
08-05-2011, 12:12 PM
Hello, Bitter.
I'm getting errors while rendering:

EXR 0.8 error: OpenEXR: Error reading pixel data from image file "E:/Interior/textures/tiles_floor_Color.exr". Tile (0, -1, 8,8) is not a valid tile.

I'm having progress so far..

One of the biggest issue were curtains which were made with the help of procedural texture and weren't baked. My noobish fault. :)
Secondly, AO with color bleed is EXTREMELY slow. I switched to detailed AO and time decreased on 30% but quality is almost the same.

EDIT: For some reason interpolation of mia materials aren't working :eek:. Does anyone has idea why?

Bitter
08-05-2011, 05:33 PM
Try converting it (the texture) again, maybe there was a corruption.

Generally if you're using a global illumination technique (Photons, FG, etc) AO+colorbleed can be redundant. It can be necessary if there's an effect like where a glowing object shouldn't darken objects it's near. But otherwise it's not fast, just pretty/detailed.

living3d
08-13-2011, 11:36 AM
Hi. Here's final image of the kitchen. Render time: 5 hours. AA 0 2, contrast: .05. I'm satisfied with times especially after against the background of almost 2 days. :). Thank you all!

http://img843.imageshack.us/img843/1754/cam5final.jpg (http://imageshack.us/photo/my-images/843/cam5final.jpg/)

Uploaded with ImageShack.us (http://imageshack.us)

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