What's New

In the 2020 What's New guide, we've mentioned that a new (and default) "Live" rendering mode can speed up your work-flow and reduce memory consumption. 

What is it?

So what is "Live" render mode versus "Background" render mode anyway? When and how should you choose which render mode to use? To answer this, I think it's best to first dissect and discuss how Visualize has traditionally executed renders from within the application.

The old way

Traditionally, when you start a rendering from within the Visualize application, there is a second, headless instance of Visualize (called OfflineRenderer.exe) that takes care of rendering the scene. What are the advantages and disadvantages of using a second executable to render your scene?  For starters, it lays the exact foundation required for doing true offline renders, ie using Queue.  In fact you can consider this traditional mode of rendering (which we now call Background render mode) akin to sending your job to the Queue and having it run/executed immediately.  Behind the scenes, a copy of your project is saved, and then loaded into OfflineRenderer.exe, and rendered with the settings specified.  The other main advantage of this work-flow, is that while the scene is being rendered, you can still use Visualize.  You can switch back to the main tab and begin making more modifications to your scene or even load up a new project. Your render will continue to process. Or you can shut down Visualize altogether and your scene will still be rendered, since it's happening in another process. In fact you may recognize this small pop up dialog, when the rendering starts.

As indicated, "Closing will not interrupt the offline render". The dialog goes on to say that doing so will "dramatically improve performance".

The new way

This dialog which appears for the traditional "background" render mode, brings us back to the introduction of our new (on by default) "Live" rendering mode.  As you know, Visualize uses your GPU to render your scenes. It uses your GPU memory to hold the geometry and textures and other assets required to load the scene in memory, and it uses the GPU's Cuda cores to process the rendering.  Well if you already have your scene loaded and rendering in the main Visualize application and viewport, it's using X amount of your GPU's resources. To be loaded again into OfflineRenderer.exe, it will again require X amount of your GPU's resources...essentially now using 2X the resources of your card!! 

With Live render mode, the scene which you already have loaded in Visualize and rendering in the viewport, is immediately rendered according to your final render settings. There is no need to silently save the scene for the OfflineRenderer.exe, or re-load it, or use 2X the GPU resources!

The new Live render mode decreases your render time in 2 ways.

1. There is no need to save/re-load the scene in the background before processing the rendering.
   • Many of you I'm sure, have worked with larger datasets which take 5-10 minutes (or even longer) to save and to open. So if it takes 20 minutes, for example, just to save and load your project, this is 20 minutes you now get back as the scene will immediately begin to render without the "behind the scenes" save/re-load.
2. You'll consume half the resources of your GPU,
   • By not having a 2nd instance of Visualize (the OfflineRenderer.exe process) required to load your scene to render it, you'll use half the GPU resources (such as GPU memory).  It is not uncommon that due to running out of GPU memory, Visualize will silently fall back to CPU mode to complete rendering, at a much slower rate. This scenario will be much less likely to occur with Live render mode since you will not tax the GPU for 2X the resources.

Conclusion

If you have a very beefy GPU setup, and you work with small/mid-sized scenes, and you've appreciated being able to modify your projects while a render was occurring, you may be happy to switch Visualize 2020 back to Background render mode...the way it always was before.

But if you're like most who have no need to make changes to your scene while it's rendering and just want the final result as quickly as possible, then the new Live render mode should be right up your alley. Anecdotally, I have to say there's something extremely gratifying when working with a larger project, and you start a render and see it immediately begin processing...no more watching the progress bar as the scene is saved and reloaded to OfflineRenderer.exe.

So give it a shot.  Load up some of your larger projects and see how Live render mode gets you a final image quicker than before!