Noob Question: Issues with Iray Preview
N00b4Ever
Posts: 299
Hi all,
What can cause the iray preview to never display the... well... the iray preview? The bar at the bottom right keeps on a never ending loop of filling up and back to zero. My scene is inside a room with six G8.1 Figures, three cameras and two spot lights per camera. I only have active (visible) a set of camera/spot lights at a time.
I tried different things, e.g. using the main window, using the aux window (~500x500), making all six G8.1 figures invisible, dome on/off, making all but the enrionment and room invisible and I never get to see the iray preview. I tried to render it and all I got was a black screen. I've done similar renders in the past without issues.
The scene duf file is less than 6 mb. I have a RTX3090 and RAM 24 gb.
What could be the issue? Could it be my file is corrupted?
I think my motherboard is slowly but surely dying (I used to have 32 gb of RAM and my SSD with my OS past away few weeks ago). Could this be part of the issue?
Thanks in advance for your responses.
Cheers.
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Comments
I don't think the size of the .duf file tells you anything useful about how much VRAM/RAM it will take to successfully render it. If you're getting a black screen when you render, you're probably exceeding the VRAM and have CPU fallback disabled. When the render starts, do you get messages about RAM consumption in the dialog window that pops up? That's a positive sign that the scene is going onto your GPU.
maybe something blocking the camera like a wall or a skydome blocking the light? what environment are you using?
Hi Gordig,
Thanks for your reply. I think you are right. I checked the log file (didn't occour to me to check it earlier) and got this:
2021-10-31 10:28:14.603 Iray [VERBOSE] - IRAY:RENDER :: 1.8 IRAY rend stat : Geometry memory consumption: 841.711 MiB (device 0), 0.000 B (host)
2021-10-31 10:29:27.576 WARNING: ..\..\..\..\..\src\pluginsource\DzIrayRender\dzneuraymgr.cpp(359): Iray [ERROR] - IRAY:RENDER :: 1.8 IRAY rend error: Unable to allocate 61.035 MiB from 18.909 GiB of available device memory
2021-10-31 10:29:27.789 WARNING: ..\..\..\..\..\src\pluginsource\DzIrayRender\dzneuraymgr.cpp(359): Iray [ERROR] - IRAY:RENDER :: 1.6 IRAY rend error: CUDA device 0 (NVIDIA GeForce RTX 3090): Scene setup failed
2021-10-31 10:29:27.965 WARNING: ..\..\..\..\..\src\pluginsource\DzIrayRender\dzneuraymgr.cpp(359): Iray [ERROR] - IRAY:RENDER :: 1.6 IRAY rend error: CUDA device 0 (NVIDIA GeForce RTX 3090): Device failed while rendering
2021-10-31 10:29:28.008 WARNING: ..\..\..\..\..\src\pluginsource\DzIrayRender\dzneuraymgr.cpp(359): Iray [WARNING] - IRAY:RENDER :: 1.6 IRAY rend warn : CUDA device 0 (NVIDIA GeForce RTX 3090) ran out of memory and is temporarily unavailable for rendering.
I'm opening the file as I'm writing this and will have a look at the message window when I check the render.
But that's for render.... is it the same issue for the preview?
Cheers.
You just answered your own question, lol.
Six G8.1 figures (and their clothes) will absolutely tank your VRAM, even moreso if some of those outfits have poorly optimized textures. Some PAs will just blithely import texture maps from a texture painting program that uses about 25% of an 8192x8192 texture map. Get yourself the Scene Optimizer product and start judiciously cutting out or reducing whatever texture maps you can.
@FSMCDesigns No, the camera is right in front of one of the figures I had one of the two spot lights blocked by a wall but I fixed it. Not sure what you mean by environment (my definition is too broad and perhaps even incorrect) But I can say other than the G8.1 figures, I have a fitness studio and a 16k HDRI from HDRI Heaven loaded as well.
@margrave Yes, I know six G8.1 figures is a lot, but I've done similar scenes successfully in the past, and was able to use the iray preview. And even render images slightly larger than 4k. Granted, that was when I had 32 gb of ram instead of 24 gb. But I'll check the pluggin you suggested.
At the moment I'm doing trial and error to see the largest image size i can render... still again... one thing is the render another thing is the preview.
Thanks all for you comments.
Cheers.
The Iray preview doesn't always work. I can't say for what exact reason. It could be from the size of the scene, number of maps, geometry, or something. IMO It's ok to try it, but never rely on it.
I'm giving up on this file... I reduced the render image size to 750x500 and DAZ crashed trying to render... I'll rebuild the scene from scratch and see how it goes.
Thanks all
The size of your rendering window doesn't mean anything, since Daz Studio has to load the same geometry and texture maps into VRAM regardless. You don't need to start from scratch, you need to lower the size of your texture maps or it'll keep happening.
This is not true - Iray definitely requires more VRAM as the render size increases.
- Greg
It does not. The size of your render has no impact on the size of the textures/geometry stored in VRAM, only how long it takes to perform the lighting calculations.
Render size does, I believe, affect memory used, but its generally trivial comapred to the memory imnpact of the scene data (even 10,000 pixels square is only 6.25 4K texture maps, which is less than most characters use).
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If you are running out of memory resizing the textures may help, or even removing them for characters who are more dsitant (or from areas pretty much covered in clothes - the legs probably don't need maps if the character is wearing trousers and shoes). Scene Optimiser provides a good way of reducing map sizes, but there are soem freebie scripts too (which lack the nice UI) or you can do it manually (if you have a character you use a lot it may be worth creating a lower-resolution map set and materials preset for future use).
I have had problems with the preview and render not agreeing on the exact position of the camera. It happens when I have something very close behind the camera, the preview showed the camera being in front of the object but in the render the surface of the object was in front of the camera. Moving the camera foreward a little bit fixed it,
Really?
Same simple scene, with only the render resolution changing from 800x800, to 3200x3200, to 9600x9600. VRAM usage was 2734MB, 3176MB, and 6927MB.
Not exactly trivial.
- Greg
I don't believe you, sorry.
I only have 8 gigabytes of VRAM and I have CPU fallback disabled, so by your argument I shouldn't be able to render a 12000x12000 image with a Genesis 8 figure in it on my GPU, and yet I can.
EDIT:
As Richard mentioned, the framebuffer does require space on the GPU, but it's generally minimal unless you're rendering at excessively high resolution. 9600x9600 (x4 for bit depth) is only 368 megabytes.
It probably has less to do with DazStudio and more to do with the Nvidia Iray driver. That's my hunch.
You don't believe what? You're right. I faked the screenshots with the render settings lol.
I don't think the equation is as simple as you'd like it to be. This is why it's so hard to pin down how much VRAM a given asset will use when rendered. Iray will use the VRAM differently in different situations.
Please don't put words in my mouth. Render size effects the amount of VRAM used and it's not trivial. Try it for yourself and post screenshots from GPUZ.
- Greg
I can confirm that a primitive sphere does indeed allocate 5.7 gigabtyes of memory for the framebuffer, per my log file. However, despite only having a few dozen vertices and no materials, a Genesis 8 figure rendered at the same resolution (9600x9600) only allocates a framebuffer of 2.9 gigabytes.
That said, that doesn't mean all that memory is required, only that it's been allocated. My log file has multiple errors about my GPU not having enough memory, only for Iray to render it anyway.
I have seen the the issue with continuing loading that stops Iray preview before from having a high number of smoothing iterations and/or collision iterations especially with interactive updates turned on for clothing. I would check the clothes before rebuilding and making sure they are not too high.
Also check out the canvas options in the render settings if you are building big scenes can cut the scene size down by doing several scenes and sewing them together.
Thanks all for your comments. I'll get back to this once I ahve some free time on my hands.
Perhaps is something with the pagefile size... right now I have it default or windows managing it. I think before my SSD died I had it at a high value. I used to have a lot of crashes in the past cause I had set it to a very low value due to issues unrelated to DAZ. Once I increased the value then the crashes stopped.