Displacement and rendering large images

[tom182]

I am rendering out a scene that uses cellular and smoke maps for the vray Disp. I rendered it out at 1400x906 in about 2 hrs using the vrimg method. All fine there, GI is by IR and LC. That is only half my issue, I am looking at the best way to render out at 5100px x 3300px, I started off using the precalc'd IR and LC maps from the smaller render, estimated render time was close to 20hrs as the disp was being presampled and that seemed to really crank up the times, Question what can I do to reduce this, I am thinking maybe having to use 2D Displacment and hence swap out the cellular and smoke maps????? reduce the max subdivs, (does the one in the render dialog override the one on the vray disp modifer?)
any ideas?
Thanks
Tom


am using max 64, on xp64 4GB RAM, Quadcore chip

[ruud3dv]

Yup, 2d displacement is the way to go.

You can render a bitmap of the displacement-mapping you're using now, or bake it if it needs to wrap around an object in a certain way. You'll need to set the resolution of the 2d-displacement to match the resolution of your bitmap. Will render a lot quicker.

The displacementsettings in the render-dialog won't be used if you use the vraydisplacement-modifier. To be sure, uncheck the checkmark for Displace in your material:maps rollout.

Greetz, Ruud

[tom182]

Tried that Ruud, but the 2D Disp seemed to blow the edges apart (tight bounds were 'on') it was able to render it out but the displ was not satisfactory
how much do I wish that there was some memory fix for vray Disp under these circumstances??????????

Thanks,
Tom

[vlado]

Normally you would increase the Edge length parameter for the displacement when you increase the resolution.

Best regards,
Vlado

[tom182]

I am going to try an revive this old thread, Original project was stalled but now I need to sort out for a similar project.

Vray Displ > here is my problem
I need to render out a very large image 5100 x 3300 ( for print)
The Disp is 3D mapping using a smoke proc map.
I can get the desired look I need when I am rendering out to a size of 640 x 480 or 1024 x 768, however when I try to render it out at 5100 x 3300 it just crashes on me. I have isolated the object with the vray disp and have tried to render it out sperately first so it could be added into the remainder of the scene in post. But this scene also crashes.

The VrayDisp (proc Smoke map) is added to a modified geosphere.
I have disabled the Net render window and saved out to VRimg but still crashes (pc is a 4GB Quad, running max64 and xp 64)

is there an exact way to mimic the result I get when using 3D proc mapping at small render size (640 x 480 or 1024 x 76 by using 2d Disp and swapping out the procedular with a render of it. I have tried replacing the proc'd smoke map with a bitmap render of it, as per previous suggestions, but alas results were way off,
Can share scene if anyone willing,

Thanks for reading
T

[vlado]

You can increase the edge length twice each time you scale the output image twice, and still get the same relative displacement detail.

Best regards,
Vlado

[3DMK]

You can increase the edge length twice each time you scale the output image twice, and still get the same relative displacement detail.

Best regards,
Vlado

As vlado stated above, if you have your displacement set to 'VIEW DEPENDENT' it will use more subdivisions as you render larger images, & you will need to adjust it accordingly.
If your scene is not too big you could try using 'WORLD' scale as this won't change no matter how big your render is.

Cheers