VRay Tiled EXR

[nookie]

I have a tiled EXR that i'm loading into the maya file image node, than connecting that into the diffuse color of the VRay material. How do i tell the tiled exr is actually working and what is the "official" workflow for using tiled exr's in vray ? The VRay for maya manual is pretty sparse on the subject and does not seem finished. Has anyone played with this some more ?

[jasonhuang1115]

I'm interested in knowing this too. I converted all my TIFs (300+ 2K textures) to tiled EXRs and expected the memory consumption will go down during render time, but found that it seems to consume the same amount of memory.

[vlado]

I have a tiled EXR that i'm loading into the maya file image node, than connecting that into the diffuse color of the VRay material. How do i tell the tiled exr is actually working and what is the "official" workflow for using tiled exr's in vray ?

Did you generate mip-maps for your tiled OpenEXR files (or, which tool did you use to write the file and with what options)? This is the correct workflow - there is nothing special to it.

Best regards,
Vlado

[vlado]

I'm interested in knowing this too. I converted all my TIFs (300+ 2K textures) to tiled EXRs and expected the memory consumption will go down during render time, but found that it seems to consume the same amount of memory.

They need to also include mip-maps; writing just a tiled file without mip-maps will make no difference. We could probably add a warning in this case.

Best regards,
Vlado

[jasonhuang1115]

How should I include the mip-maps during the converting process? I am using the GUI version of the img2tiledexr tool and I didn't see option for choosing the filter type for converted exrs?

Edit: or the converted EXRs are automatically teiled mipmap EXRs? What I then need to do is specify the filter type in the Maya file node?

[Metzger]

By default imgtotiledexr writes out tiled mipmaps. You have to specifiy on the file read node. Change from quadratic to mipmap and you should be good.

Also under the settings tab of V-Ray globals, under systems. Set geometry to dynamic and give it a memory limit. You might have it on automatic causing all of your geo to eat up the ram.

If you are using Displacement maps from zbrush you don't want the displacement maps to be tiled or mipmapped though. Also if you are using Displacement you might want to turn View dependent on so it sub divides based on the view, instead of subdividing all of your geometry. If you have glass objects, you will want to make sure View dependent is turned off or you will get flicker in your refraction.

If you aren't using displacements then you can ignore my last paragraph.

[jasonhuang1115]

pure gold, Scott. Really appreciate your input. I will give a shot tomorrow early morning. The asset I am dealing with has 300+ 2k tif textures across 20+ UV tiles. During render time, it eat up about 9.5 GB of RAM even with displacement and subdivision set to Edge length of 4 and Max subdivs of 1 (I should have checked the view dependent). The textures along eat up so much RAM on my 12 GB workstation and pushing the RAM consumption to 11.8 GB. Hope with your advise, there will be more RAM freed up.

The displacement maps I am applying to the scene is generated from Mudbox with multiple UV tiles (not tiled MIP-map EXRs). I read in the doc. that if tiled EXR is used for displacement, the min and max displacement values need to be specified. I will stay away from that for now for simplicity.

Thanks.

[Metzger]

I haven't done anything with displacement from Mudbox. Only zbrush. But I know that you don't have to set a min and max displacement value if you paint maps at the scale you are going to render at. So if a someone gets a model to paint, make sure its in centimeters when they paint it.


Becareful on the UVs tiles. If you have that many maps you are gonna drive your systems people crazy with the IO on those file reads. I would definitely use larger maps with less UV tiles if possible.

Hope it helps.

-Scott

[jasonhuang1115]

I changed all original TIF maps to tiled mipmap EXRs except the normal and displacement maps. Unfortunately, the scene consumed about the same, if not more, RAM to render. I read here (http://www.chaosgroup.com/forums/vbu...=tiled+exr+RAM) that the overall RAM consumption won't be much different with using tiled EXRs to replace original JPG or TIF textures. It will be great to get a confirmation from you or Vlado on this.

I am curious about what regard the statement of rendering more efficiently with tiled mipmap EXRs actually refers to? For I/O or RAM consumption or something else?

[vlado]

How should I include the mip-maps during the converting process? I am using the GUI version of the img2tiledexr tool and I didn't see option for choosing the filter type for converted exrs?

Edit: or the converted EXRs are automatically teiled mipmap EXRs? What I then need to do is specify the filter type in the Maya file node?

If you used img2tiledexr, then they have mip-maps by default. You need to set the filtering mode to "Mip-map" and make sure that texture filtering is enabled in the V-Ray settings.

Best regards,
Vlado

[jasonhuang1115]

If you used img2tiledexr, then they have mip-maps by default. You need to set the filtering mode to "Mip-map" and make sure that texture filtering is enabled in the V-Ray settings.

Best regards,
Vlado

Thanks, Vlado. I've applied the setting accordingly. However, the overall memory consumption didn't decrease as I mentioned in my previous reply. I am curious about what regard the statement of rendering more efficiently with tiled mipmap EXRs actually refers to? For I/O or RAM consumption or render time or something else?

[vlado]

I changed all original TIF maps to tiled mipmap EXRs except the normal and displacement maps. Unfortunately, the scene consumed about the same, if not more, RAM to render. I read here (http://www.chaosgroup.com/forums/vbu...=tiled+exr+RAM) that the overall RAM consumption won't be much different with using tiled EXRs to replace original JPG or TIF textures. It will be great to get a confirmation from you or Vlado on this.

Then it may not be textures that are the problem; if you can get us the scene in question to vraymaya@chaosgroup.com we will be able to tell you more.

Best regards,
Vlado

[jasonhuang1115]

Then it may not be textures that are the problem; if you can get us the scene in question to vraymaya@chaosgroup.com we will be able to tell you more.

Best regards,
Vlado

VRay chewed through the scene just fine on my machine with 12 GB (11.6 GB consumed). I was just hoping that with tiled EXRs the RAM consumption can be lower.