Creating Primitive NURBS Objects

GenNURBSLatheSurface()

The GenNURBSLatheSurface() function generates a NURBS surface of revolution given an input curve, origin, up axis, and start and end angles. The output of this function is a NURBS CV Surface that matches the definition, not a relational surface.

Parameters:

• NURBSCurve& curve - This is the NURBS curve that is revolved.
• Point3& origin - Specifies the origin of the revolution.
• Point3& north - This is the axis that specified the up direction.
• float start - This is the start angle of the revolution in radians.
• float end - This is the end angle of the revolution in radians.
• NURBSSurface& surf - The surface definition is returned here.

GenNURBSSphereSurface()

The GenNURBSSphereSurface() Generates a NURBS sphere as a non-closed NURBS Surface. Note that this is a CV surface that matches the definition, not a relational surface.

Parameters:

• float radius - The radius of the sphere.
• Point3& center - The center point of origin of the sphere.
• Point3& northAxis - This specifies the up axis. Use Point3(0,0,1) for the Z axis for example.
• Point3& refAxis - This is the direction of the seam. The sphere primitive uses Point3(0,-1,0) as this value.
• float startAngleU - The start angle for the sphere in the U direction, specified in radians.
• float endAngleU - The end angle for the sphere in the U direction, specified in radians.
• float startAngleV - The start angle for the sphere in the V direction, specified in radians.
• float endAngleV - The end angle for the sphere in the V direction, specified in radians.
• NURBSSurface& surf - The surface definition is returned here. This is a CV surface that matches the definition, not a relational surface.

GenNURBSCylinderSurface()

The GenNURBSCylinderSurface() function generates a NURBS cylinder as a non-closed NURBS Surface. Note that this is a CV surface that matches the definition, not a relational surface.

Parameters:

• float radius - The radius of the cylinder.
• float height - The height of the cylinder.
• Point3& origin - The origin of the cylinder.
• Point3& symAxis - The axis of symmetry. The standard cylinder primitive specifies Point3(0,0,1).
• Point3& refAxis - This is the direction of the seam. The standard cylinder primitive specifies Point3(0,1 ,0).
• float startAngle - The start angle in radians.
• float endAngle - The end angle in radians.
• NURBSSurface& surf - The surface definition is returned here.

GenNURBSConeSurface()

The GenNURBSConeSurface() function generates a NURBS cone surface as a non-closed NURBS Surface. Note that this is a CV surface that matches the definition, not a relational surface.

Parameters:

• float radius1 - One of the radii of the cone.
• float radius2 - The other radius of the cone.
• float height - The height of the cone.
• Point3& origin - The origin of the cone.
• Point3& symAxis - The axis of symmetry.
• Point3& refAxis - This is the direction of the seam.
• float startAngle - The start angle in radians.
• float endAngle - The end angle in radians.
• NURBSSurface& surf - The surface definition is returned here.

GenNURBSTorusSurface()

This GenNURBSTorusSurface() function generates a NURBS torus surface as a non-closed NURBS Surface. Note that this is a CV surface that matches the definition, not a relational surface.

Parameters:

• float majorRadius - This is the radius of the entire 'donut' shape.
• float minorRadius - The is the radius of the 'tube'.
• Point3& origin - The origin of the cone.
• Point3& symAxis - The axis of symmetry.
• Point3& refAxis - This is the direction of the seam.
• float startAngleU - The start angle of the torus in the U direction.
• float endAngleU - The end angle of the torus in the U direction.
• float startAngleV - The start angle of the torus in the V direction.
• float endAngleV - The end angle of the torus in the V direction.
• NURBSSurface& surf - The surface definition is returned here.

CreateNURBSLatheShape()

The CreateNURBSLatheShape() function generates a NURBS object based on the specified lathe (surface of revolution) definition and returns a pointer to it. This is used by the lathe modifier.

Parameters:

• IObjParam* ip - The 3ds Max interface pointer. If non-NULL, this is used to get at the 3ds Max function to do unique naming. If a NULL is specified the names are not made unique.
• TSTR name - The name for the object. If the pointer above is non-NULL this name is made unique.
• TimeValue t - The time at which to revolve the shape.
• ShapeObject *shape - Points to the shape object to revolve. Note that if the ShapeObject pointed to is a bezier spline then capping won't work properly.
• Matrix3& axis - This specifies the axis of revolution.
• float degrees - The angle for the surface of revolution in degrees.
• int capStart - Specifies if the surface should be capped at the beginning: TRUE to cap; FALSE to leave open. Note that this is only used if the ShapeObject is a NURBS curve.
• int capEnd - Specifies if the surface should be capped at the ending: TRUE to cap; FALSE to leave open. Note that this is only used if the ShapeObject is a NURBS curve.
• int capType - This parameter is not currently used and the value passed is ignored.
• BOOL weldCore - TRUE to collapse any coincident vertices at the center of the surface; otherwise FALSE.
• BOOL flipNormals - TRUE to invert the orientation of surface normals; otherwise FALSE.
• BOOL texturing - TRUE to generate mapping coordinates; otherwise FALSE.
• int segs - This parameter is not currently used and the value passed is ignored.
• BOOL matIds - If TRUE special material Ids are assigned to the surfaces and caps.
• BOOL shapeIDs - If TRUE shape IDs are used. When on, this function uses the material ID values assigned to segments in the spline to be lathed, or curve sub-objects in the NURBS curve to be lathed. This is available only when matIds is TRUE.

CreateNURBSExtrudeShape()

The CreateNURBSExtrudeShape() function generates a NURBS object based on the specified extrusion definition and returns a pointer to it. This is used by the extrude modifier.

Parameters:

• IObjParam* ip - The 3ds Max interface pointer. If non-NULL, this is used to get at the 3ds Max function to do unique naming. If a NULL is specified the names are not made unique.
• TSTR name - The name for the surface. If the pointer above is non-NULL this name is made unique.
• TimeValue t - The time at which to extrude the shape.
• ShapeObject *shape - Points to the shape object to extrude. Note that if the ShapeObject pointed to is a bezier spline then capping won't work properly.
• float amount - Specifies the height of the extrusion.
• int capStart - Specifies if the surface should be capped at the bottom: TRUE to cap; FALSE to leave open. Note that this is only used if the ShapeObject is a NURBS curve.
• int capEnd - Specifies if the surface should be capped at the top: TRUE to cap; FALSE to leave open. Note that this is only used if the ShapeObject is a NURBS curve.
• int capType - This parameter is not currently used and the value passed is ignored.
• BOOL texturing - If TRUE texture coordinates are assigned; otherwise they are not.
• BOOL matIds - If TRUE special material Ids are assigned to the surfaces and caps.
• BOOL shapeIDs - If TRUE shape IDs are used. When on, this function uses the material ID values assigned to segments in the spline to be extruded, or curve sub-objects in the NURBS curve to be extruded. This is available only when the matIds parameter is TRUE.