VRML-NURBS Exporter and File Converter

Export plugin for 3D Max

The exporter is a plugin that allows the direct export of NURBS models from Kinetix 3D Studio Max to VRML using the proposed nodes. The plugin needs to be copied to the plugin subdirectory of 3D Studio MAX.

Features

• TextureTransform is exported. The transform in the material properties is not exported. Choose Subobjects and Surface in the Transform Surface Menu. Edit the Material Properties. Do not forget to copy the texture to the local directory.
• Control Point Animation: The motion of the control points is sampled over time and converted to a spline description. The samples are used to generate a B-Spline description of the motion path of every vertex. Afterwards a complexity reduction needs to be applied (knot reduction). The angle field in the export options gives the upper bound for the tangents of points, which are removed. A high number of samples and and small angle lead to more exact results, but increases the file size. The spline description is exported in a NurbsPositionInterpolator and routed to the surface.

Some Hints for Good Results

• Use 'Make Surface Independent' (modifier/subobjects/surfaces) before exporting to VRML NURBS
• Adapt the scene coordinate system to meters.
• Check Verbose VRML Output in the export options dialog in order to get further hints to names of surfaces, supported shapes etc.
• Use Collapse Transformations in the tools menu in order to apply rotations and scale to dependend child nodes.
• If the tessellation in blaxxun BS Contact is too coarse in areas of high curvature, refine the control mesh in those areas.
• Consider using a 3D mesh texture paint program in order to draw textures with the right distortion.
• For closed objects, place the seams at unimportant parts of the model (e.g. at the bottom or rear).
• Normals for shading are computed directly using NURBS tangent evaluation, so avoid situations where this tangent will be zero.
• The u/v tessellation fields in the NURBS surface code can be used to give an initial tessellation density hint.
• If the BS Contact automatic NURBS LOD is too coarse in some situations, consider adding a conventional VRML LOD with a minimum triangle IndexedFaceSet for large distances.

Known Limitations

• Only standard CV-surfaces are supported.
• Trimmed NURBS surfaces are not supported. Alternativly these objects can be exported as a triangular mesh with the conventional VRML exporter.
• Texture coordinates are automatically generated by the BS Contact client, so MAX mappers will not work.
• The 2.5 version supports only CV animation.

Export plugin for 3D Studio Max 3.0

Download blaxxun 3DSMAX VRML NURBS Export.

The export plugin is integrated in the standard VRML97 exporter provided by Kinetix. Thus NURBS primitives can easily be combined with conventional VRML primitives.