OTOY Forums

Hi all....

I am working on a pretty large scene, and noticed that there is a huge difference in system memory usage when using IPR VS an F9 render. When opening ipr on the scene, memory usage goes up a little bit and opens pretty fast. When using F9 render it almost caps out my systems memory and it takes forever to load.

Any idea why this is?

Are you rendering a high resolution image? The problem can be related to use a lot of render passes and high resolution images. In Octane 3 all the frame buffers are stored in the CPU RAM, so large images with a lot of passes can need to a lot of RAM to store all the data.

Can you please test your scene using the same resolution for the IPR and for the final image, and perhaps disabling the passes node?

-Juanjo

Other problem can be the LightWave native subdivision surfaces. Are you working with SDS objects? ... the IPR uses the display settings for the subdivision level while the final F9 render uses the render subdivision settings. Perhaps your scene has high subdivision level settings only for rendering.

-Juanjo

I got it to be a little better. I am not sure if this is a bug or if my scene may have just gotten weird. I do have subdiv surfaces, but there render level is the same as ipr. I do have lots of instances however. On the terrain object, I have 4 instance generators. When all are checked on it takes up a ton of ram and sometimes does not render all the instances. When only the first generator is checked on, it takes up less memory, and renders the whole scene correctly, and ALL the other unchecked instance generators STILL show up in the render. THey only vanish from the render when the TOP most generator is unchecked. It's like the TOP instance generator is a master for all the ones below it in the list.

It is also like when the instance generators below ARE checked, they are doubling the amount of instances in the render because it takes up way more memory.

hope this makes sense. LOL.

Thanks. !

mstewart152 wrote:When only the first generator is checked on, it takes up less memory, and renders the whole scene correctly, and ALL the other unchecked instance generators STILL show up in the render. They only vanish from the render when the TOP most generator is unchecked.

The first generator enable/disable behavior is a known limitation. The LightWave SDK doesn't have the functions needed to know which instance generators are enabled and which are not, so the plugin only checks the state of the first one ... if it is enabled all the generators are rendered, if it is disabled all the generators are removed from the render.

mstewart152 wrote:It is also like when the instance generators below ARE checked, they are doubling the amount of instances in the render because it takes up way more memory.

This is what I don't understand, the number of instances should be the same, and the plugin is not going to need more memory to load or render them. Perhaps the problem is in the Layout, processing the enabled instance generators to get the motion blur, or something like that. I will make some tests to see if I can reproduce this problem here.

-Juanjo

one more thing i noticed on this shot im working on, The Zdepth channel seems to be missing motion blur.

juanjgon wrote:

mstewart152 wrote:When only the first generator is checked on, it takes up less memory, and renders the whole scene correctly, and ALL the other unchecked instance generators STILL show up in the render. They only vanish from the render when the TOP most generator is unchecked.

The first generator enable/disable behavior is a known limitation. The LightWave SDK doesn't have the functions needed to know which instance generators are enabled and which are not, so the plugin only checks the state of the first one ... if it is enabled all the generators are rendered, if it is disabled all the generators are removed from the render.

mstewart152 wrote:It is also like when the instance generators below ARE checked, they are doubling the amount of instances in the render because it takes up way more memory.

This is what I don't understand, the number of instances should be the same, and the plugin is not going to need more memory to load or render them. Perhaps the problem is in the Layout, processing the enabled instance generators to get the motion blur, or something like that. I will make some tests to see if I can reproduce this problem here.

-Juanjo

ah ok... gotcha... knew there was something going on there. Thanks. !!!!

mstewart152 wrote:one more thing i noticed on this shot im working on, The Zdepth channel seems to be missing motion blur.

Do you have the "Distributed Ray Tracing" option enabled in the Info passes tab?

-Juanjo

I do now!!!... Thanks!!!!! hehe.

made a little more progress into this instancing thing.

If I load the scene with it saved with the instance generators below the first one off, it will not render them. If i check them on to populate them, then turn them back off, they show up in the F9 render. Just a strange behavior.