This page provides information on the Subdivision and Displacement Quality attribute set that can be added to meshes.

 

Page Contents ×

Overview


The attributes in this section affect the quality of V-Ray subdivision and displacement. They can be added to any polygonal mesh object.

UI Path


 

||Select mesh|| > Attribute Editor > Attributes menu > VRay > Subdivision and Displacement Quality

 

 

 

Subdivision and Displacement Quality Attributes





Override Global Settings – When enabled, the settings in the Default Displacement and Subdivision rollout are overridden for the current object. 

View dependent – When enabled, Edge length determines the maximum length of a subtriangle edge, in pixels. A value of 1.0 means that the longest edge of each subtriangle is about one pixel long when projected on the screen. When View-dependent is off, Edge length is the maximum subtriangle edge length in world units.

Edge length – Determines the quality of the displacement or subdivision. Each triangle of the original mesh is subdivided into a number of subtriangles. More subtriangles means more detail in the displacement, slower rendering times and more RAM usage. Less subtriangles mean less detail, faster rendering and less RAM. The meaning of Edge length depends on the View-dependent parameter above. For more information, see the Edge Length example below. 

 Max. subdivs – Controls the maximum subtriangles generated from any triangle of the original mesh. The value is in fact the square root of the maximum number of subtriangles. For example, a value of 256 means that at most 256 x 256 = 65536 subtriangles are generated for any given original triangle. It is not a good idea to keep this value very high. If you need to use higher values, it will be better to tessellate the original mesh itself into smaller triangles instead.





 

Example: Edge Length 


The image below was rendered with a Edges Map | VRayEdgesTex texture in the Diffuse slot of the material, so you can see the original triangles of the mesh. Additionally, we turned on the Faceted option in the VRayMtl. Now, V-Ray will not only smooth the surface normals, but will also automatically apply a normals map that represents the normal of the perfect displaced surface, which will make the surface look a lot more detailed that it actually is.

View-dependent is turned on, and it refers to pixels in the original image, not the zoomed-in image you get with a blow-up rendering. This is why we were able to do a blow-up rendering to see the individual subtriangles better. Click the images for a larger view:


Edge Length 0.5



Edge Length 0.5 Close up view


 

 
Edge Length 1.0


Edge Length 1.0 Close up view


 


Edge Length 2.0



Edge Length 2.0 Close up view


 


Edge Length 5.0



Edge Length 5.0 Close up view


 


Edge Length 10.0


 
Edge Length 10.0 Close up view




 



 Scripting

 Add to node:

vray addAttributesFromGroup "pSphereShape1" "vray_subquality" 1;

Attributes:

vrayOverrideGlobalSubQual
vrayViewDep
vrayEdgeLength
vrayMaxSubdivs