Maya/Vray RT active view

[JulianBoolean]

Hey everyone,

I am pretty new to this forum but I have been using vray for a few years now. I recently got into the vray 3.0 beta and I got to say.... its amazing. Great job on this new version, definitely a game changer for me in terms of gpu rendering. I had a few questions though about Vray Gpu Rendering. So recently I just bought two 780GTI graphics cards for my system. I hooked them up and they are running perfectly fine. So when I activate the RT renderer in one of the viewports, is there a way for me to control how much of one of the graphics cards controls the opengl viewport display and how much the other graphics card handles the actual real time gpu rendering. Is that even possible, or does it just automatically balance what it is doing. It would be nice if I can set the real time engine to not use as much of the graphics card while I am updating shaders, textures, etc. so that I can see the updates quickly but not have it put all of its rendering power into rendering the final image. Is that what Gpu ray bundle size and gpu rays per pixel is for?

Also when I turn on "show statistics" it doesnt actually show me the time it takes to render in seconds or minutes. Is there something else I need to turn on or do I need to do the math for what it is showing me.

I am also unclear on what the GPU texture size does, could someone explain this to me.

Also I sort of understand the max. render time setting, max paths per pixel and max noise but I am not really sure how to set that for optimal use. For final gpu frames is it best to set max noise to .003 and max paths per pixel to something around 800, or should I set the max render time and leave max paths per pixel at 500 and max noise at 0. I know this probably all depends on the scene and what is in the scene. It would just be nice to understand what optimal settings would be for a base scene.

Thanks for the help! I really appreciate it.

Here is what I am running:
2 780 gti in non sli
Maya 2014 , Vray 3 ( the nightly build from the Oct. 15th , I can get the actual build when I get home from work)

[_martin]

Hi,

I am also pretty new to V-Ray for Maya but I think I can give you some answears before someone more qualified will do so.

The "show statistics" is currently bugged, meaning that it simply doesn't show up while it should, it will be fixed in the next stable version though.

The GPU texture size option resizes all textures in you scene to the value that is entered in the box in the options. This is a nice feature to bottleneck the texture data that is being sent to you GPU. Otherwise, in situations where you run out of memory, you would have to manually downscale all of your textures which can be a tedious task.

Concerning your last question, I rather leave it to somebody with more experience. I can say though, that for me (I am doing mostly animations) even .001 is sometimes too much noise for a final render.

I hope that helped a bit.

Cheers

[tashko.zashev]

Hi Julian,

So when I activate the RT renderer in one of the viewports, is there a way for me to control how much of one of the graphics cards controls the opengl viewport display and how much the other graphics card handles the actual real time gpu rendering. Is that even possible, or does it just automatically balance what it is doing. It would be nice if I can set the real time engine to not use as much of the graphics card while I am updating shaders, textures, etc. so that I can see the updates quickly but not have it put all of its rendering power into rendering the final image. Is that what Gpu ray bundle size and gpu rays per pixel is for?

Unfortunately there is no option to directly control the GPU usage during the rendertime (RT), therefore our advise is to use one graphic card for RT calculations and another to perform the display function. When you go to the final production stage (if you use RT GPU as production renderer) you can enable both graphic cards using the OpenCL device select tool.

Decreasing the Ray bundle size and Rays per pixel values you could bring more GPU power for VFB and viewport updates, but there will be still noticeable lack of performance.

Also when I turn on "show statistics" it doesnt actually show me the time it takes to render in seconds or minutes. Is there something else I need to turn on or do I need to do the math for what it is showing me.

It is a know issue and w are working to fix it.

I am also unclear on what the GPU texture size does, could someone explain this to me.

Tish option is very useful in cases that the scene has a lot of hires textures and the graphic card installed has not enough memory to handle them all.

Also I sort of understand the max. render time setting, max paths per pixel and max noise but I am not really sure how to set that for optimal use. For final gpu frames is it best to set max noise to .003 and max paths per pixel to something around 800, or should I set the max render time and leave max paths per pixel at 500 and max noise at 0. I know this probably all depends on the scene and what is in the scene. It would just be nice to understand what optimal settings would be for a base scene.

As you have pointed out, it depends on the scene.
The workflow could be similar to the one with V-Ray Advanced renderer. Just render few regions where the the noise is more apparent and find how high "max paths per pixel" value should be set to get acceptable render result. The use this value for the final render.
Another approach is to use the "Max render time" option and specify exact render time for the current frame.
Generally in all cases you should run few tests before starting the final render with V-Ray RT.

The "Max Noise" will force the engine to stop rendering in areas where the noise threshold has been reached. There are few minor issues related to this option that we still need to fix, but setting it to 0,001; 0,003 will have an impact to the final frame render time.

[JulianBoolean]

Thank you guys for answering my questions. This has helped alot!