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Dillon
01-25-2013, 08:40 PM
Hi Folks,

Have a strange one here!

I bought Elements 3D for after effects, with the new Metropolitan pack. AWESOME by the way. I imported their 6 various city blocks (FBX) and instanced them in layout.

Playing with lights, radiosity, etc, and this anomaly stays in the RENDER, but NOT in VPR. I can't for the life of me figure out why the render would show the streaking but VPR shows it perfectly.

Attached is a screen grab of the render next to VPR.

Any ideas?

Highly recommend purchasing Elements 3D and the Metropolitan model pack!

JoePoe
01-25-2013, 09:26 PM
I think I can see a little of the same pattern of anomaly in the vpr, granted nowhere near the same.
Anyway, looks like smoothing to me. Is smoothing on? If yes, try taking it way down.... see what 10 does. Are you sure the geomtry remained clean fbx to LW. Maybe take a look in modeler. Perhaps there are ploys on top of ploys.

(plus... i'd go up a level in AA on the F9. That edge is pretty jagged. Don't really think that'll help the issue, but what the hey.)

Dillon
01-26-2013, 09:53 AM
Hey JoePoe,

Thanks for your feedback. I haven't yet started working AA, as I'm trying to resolve the weird artifacting. Here's a better sample. Smoothing is turned off for all surfaces. Looks like a trip to modeler to inspect the models. However, the smearing happens across different geometry. I've never seen duplicated polygons render out this way. Course, the last version I worked with aggressively was v7...

Thanks again.

Dillon


I think I can see a little of the same pattern of anomaly in the vpr, granted nowhere near the same.
Anyway, looks like smoothing to me. Is smoothing on? If yes, try taking it way down.... see what 10 does. Are you sure the geomtry remained clean fbx to LW. Maybe take a look in modeler. Perhaps there are ploys on top of ploys.

(plus... i'd go up a level in AA on the F9. That edge is pretty jagged. Don't really think that'll help the issue, but what the hey.)

MarcusM
01-26-2013, 10:05 AM
This models have only triangles?

Dillon
01-26-2013, 11:10 AM
All tri's.

Rebuilt the scene using LWO and the issue still arises.

At one point, I rebuilt, and the problem was gone. But when I packaged the scene into a new directory, some textures got lost (I had modeler open - UGH!!). So I trashed it, started over, and now I have the problem again. Even after rebuilding from scratch. The problem is on the instances, not on the original geometry.

Thanks guys.

Dillon

ncr100
01-26-2013, 11:18 AM
Really does look like two polygons sharing the same location. But you've explored that.... Try breaking the model by gradually deleting, and re-rendering one of the problematic areas? Narrow down the problem.

Phil
01-26-2013, 11:53 AM
There are alternate models that are build with quads. Available in the same package as FBX and OBJ.

JoePoe
01-26-2013, 11:57 AM
just curious, did you get feedback from merging and unifying??
(xx points eliminated? xx polys eliminated?)

...... problem only on instances..... hmmm.
Have you tried rendering without images? See if you get the same result with a simple (or no) surface treatment.

Dillon
01-26-2013, 12:07 PM
I thought to do this too, but they don't supply the FBX quad version of the street layout objects.

The OBJ files come in missing all their textures and its a nightmare to try and reassociate. The FBX files automatically link to the textures. Too bad they didn't supply the quad FBX files of the street layout objects.


There are alternate models that are build with quads. Available in the same package as FBX and OBJ.

JoePoe
01-26-2013, 12:17 PM
There is a plugin (several I'm sure) that will reconstitute tris back into quads (works best on not too complicated of an object.... which you seem to have)

Merge trigons (http://www.lwplugindb.com/Plugin.aspx?id=aadc8f36)

Not sure how your textures will react to the process though.
You can run the plug and export as FBX out of Lightwave to try and preserve the texturing.

(btw how are the textures handled? UV? Simple planar mapping? etc?)

Dillon
01-26-2013, 12:37 PM
Here's another example:

1. Took model object and cloned it. Rendered. No issues.

2. Instanced model object and rendered. Strange smudging.

There's a distinct difference in how the textures are being handled when the object is instanced. The smudging happens on the instanced models.

What am I not understanding?

Sensei
01-26-2013, 01:53 PM
Polygons are flipped. Or maybe even vertex normals are flipped, if you're using them.

50one
01-26-2013, 02:02 PM
Here's another example:

1. Took model object and cloned it. Rendered. No issues.

2. Instanced model object and rendered. Strange smudging.

There's a distinct difference in how the textures are being handled when the object is instanced. The smudging happens on the instanced models.

What am I not understanding?

I'm not 100% sure, but I think those models were generated in 3dsmax, so probably there is some kind of smoothing, vertex map that 3dsmax exports - it happened to me few times, but I've cleaned the models in modo.

- - - Updated - - -

I could check if there's anything weird in your mode if you want of course, let me know via PM.

Simon

OnlineRender
01-26-2013, 02:17 PM
sounds like something is slipping in terms of materials

Dillon
01-27-2013, 06:02 PM
SOLVED!!

It was the mipmap quality. I turned it off in the color texture. Weird artifacts are gone.

Which begs the question (I feel like a newbie again) - what is mipmap, and why does it affect instances differently than clones? Cloned objects render without the weird artifacts, whereas the instances have the weird smudges on them.

Glad to have resolved this!