The Superquadric source can be used to add a polygonal superquadric to the 3D scene. The resolution in both the latitude (phi) and longitude (theta) directions can be specified. Roundness parameters control the shape of the superquadric. The Toroidal boolean controls whether a toroidal superquadric is produced. If so, the Thickness parameter controls the thickness of the toroid: 0 is the thinnest allowable toroid, and 1 has a minimum sized hole. The resulting superquadric can be translated, rotated, and scaled using the Actor control area of the Display tab for this source, and it can be interactively positioned using the Move operation of the camera. The object created by this source is a vtkSuperquadricSource object, and the output of this source is vtkPolyData. The output polydata has point normals and texture coordinates defined. Four example superquadric objects are given below. Note that this is a powerful source object in that it can be used to create a sphere, a box, a torus, or a variety of other shapes simply by adjusting the roundness parameters.
The Superquadric source has the following parameters:
Center: This coordinate represents the center of the superquadric. By default this value is (0,0,0).
Scale: These three values can be used to scale the superquadric in X, Y, and Z. The normals will be computed correctly even with anisotropic scaling.
Theta Resolution: This number represents the number of division in the theta (longitudinal) direction. The default theta resolution is 16. This value will be rounded to the nearest multiple of 8.
Phi Resolution: This number represents the number of division in the phi (latitudinal) direction. The default phi resolution is 16. This number will be rounded to the nearest multiple of 4.
Thickness: If the Toroidal box is checked, this value represents the thickness of the object as a value between 0 and 1. A value close to 0 leads to a thin object with a large hole, and a value near 1 leads to a thick object with a very small hole.
Theta Roundness: Define the roundness in the theta direction. A value of 0 represents a rectangular shape, a value of 1 represents a circular shape, and higher values represent higher order shapes. The default value is 1.
Phi Roundness: Define the roundness in the theta direction. A value of 0 represents a rectangular shape, a value of 1 represents a circular shape, and higher values represent higher order shapes. The default value is 1.
Size: This value represents an isotropic size of the superquadric. By default it is 0.5. Note that The Size and Thickness parameters control coefficients of superquadric generation, and may do not exactly describe the size of the superquadric.
Toroidal: If this box is not checked (the default) the generated superquadric will not contain a hole. If checked, a toroidal object is generated.