Opening MAYA files into VRED Scene for Rendering

[Anonymous]

Hello Everybody,

We tried to open a model using different formats from MAYA in order to prepare the Rendering Scene,  but the geometry quality was totally poor.

The MB files are imported not as a "Surface", are imported as a Tesselated geometry but does not allow to Re - Tesselate, in order to get more triangles into the shape and optimize the geometry.

Is there any special process in order to get a high quality surface from MAYA and then tesselate it into VRED?

Thank you very much,

Ricardo

[richardlevene]

Hi Ricardo,

In maya, is the geometry smoothed? Or were you using the 3 key to previous smooth subdivision of the geometry?

Richard

[michael_nikelsky]

Hi,

VRED only imports NURBS and Polygons. NURBS will be imported as surfaces and can be retessellated. Polygons however are imported as is, and can´t be retessellated per definition. VRED does not support Subdivision Surfaces, so if you want to keep any subdivision like properties you will need to apply them manually in Maya before exporting.

There is, however, the option to apply a phong type subdivision inside VRED if you go to scenegraph->edit->geometry->subdivide geometry. However, this sort of subdivision is only based on the vertex normals of a triangle, so any hard edges in the geometry will result in cracks between triangles. 

Kind regards

Michael

[Anonymous]

Hi Richard,

We have tried to keep the surfaces in MAYA as smoothed geometry, in order to keep continuity and good surfaces but opening in VRED, surfaces are automatically "tesselated", even when deactivating the tesselation option when the file is being opening.

It is like the kind of surfaces from MAYA, were not well recognized and the geometry is bad tesselated.

Thanks!

[Anonymous]

Hi Michael,
Trying to open NURBS in VRED, directly are converted into Polygons. Even deactivating the "Tesselation" option when importing.

Trying to open Polygons in VRED, they are not allowed to re - tessellate. So the continuities G1 - G2 - G3 are totally destroyed in the 3D model, and in rendering they give a poor appearance.

Phong is not a option, because you will have thousands of triangles but you can not optimize geometries.

It means, there is no option to keep good quality from MAYA models?
I have tried to open CATIA Files, not CLASS A Surfaces models, and convertion is perfect keeping geometry quality and nodes structure.

Thank you very much,

Ricardo

[michael_nikelsky]

Sorry, I still don´t understand what you are trying to do.

First of all: Which version of VRED are you using?

If you import NURBS, they will be tessellated on import in VRED since the Maya Tessellation is usually not usefull for our customers. This, however, means that you have to set accurate tessellation parameters.

If you import polygons, they are imported as is. Polygons, per definition, never have G2 or G3 continuities since they are discrete. It is not possible to retessellate polygons since this would require them to have some mathematical base definition, which they don´t have. If the polygons from Maya look different in VRED then this is because you have applied some sort of interactive smoothing in Maya that is not converted. Only the Base-Mesh is converted (press 1 in Maya to see what is exported), any subdivision or catmull-rom smoothing is ignored. So you have to manually apply the smooth in Maya by using Mesh->Smooth if you want to have the smooth surface.

Kind regards

Michael

[Anonymous]

Hi Michael,

I want to share with you (all) some pictures, just to explain what is our problem trying to open MAYA files.

Thank you very much.

Ricardo

[michael_nikelsky · Accepted solution]

Ok, I see you are using a 2014 VRED Version, right? There have been a lot of improvements in the VRED2015 Version regarding FileIO and NURBS support, so if possible please try one of these versions (you should be able to download a demo).

Could you also share a simple maya example file? Can be as simple as a sphere as long as it reproduces the issue.

[Anonymous]

You are right it is 2014.

I will try with 2015.

For sure, I will send you the Maya file. (The one we are working with).

Thank you