7 High-Level Libraries

High-level libraries fulfill the advanced needs of applications using the VISTA data level. They augment the syntactical broadness of the upper PAI layers with the semantic functionality needed by applications.

For example, the VISTA Material Server library (MAT) uses the PAI library to store its materials on a PBF in a very specific way, which is only possible because PIF was designed to be very flexible and general. Materials could be read and written using many PAI functions directly as well, but high-level libraries are more than sophisticated PAI-macros. Imposing their own specialized memory representation they allow TCAD data to be effectively manipulated in-core, using the PAI library to store and retrieve those high-level data objects to and from PLBs.

The following features are provided by high-level libraries:

Semantical consistency
Some of the ambiguities not resolved by the application layer as stated in Section 6.2 are tackled by the high-level libraries. The C List Support (CLS) library see Section 7.2.4 for example ensures an unambiguous geometry construct by enforcing reads and writes of lines consisting of exactly two points. A standard scheme for writing and reading PIF attributes is enforced by the Geometry Attribute Support (GAS) library see Section 7.2.1.

Functionality
High-level libraries enable applications to easily manipulate data with simple yet powerful procedural interfaces. Whole geometries can be merged, segments and boundaries extracted and manipulated with the help of the Geometry Two-dimensional Support (G2S) library see Section 7.2.2. Grids and attributes can be created, destroyed, read, written, and manipulated with the object-oriented interface provided by the Grid Support (GRS) library see Section 7.1.

Specialization
The functionality of the lower PAI levels is combined and focussed onto specific requirements of TCAD applications. While the PAL was designed to provide a reliable array-oriented interface for FORTRAN applications, this representation is not always appropriate for C applications. Therefore most VISTA high-level libraries provide an object-oriented view of the data they are dealing with, which is ideally suited for C and advanced FORTRAN applications working with opaque object pointers (these are mapped to integers in the FORTRAN language binding).

  
Figure 7.1: Structure of the VISTA high-level libraries

• 7.1 GRS
  • 7.1.1 Architecture
    • The Single Linked List and Array Base Classes
    • Classes derived from the PIF Syntax
    • The PIF Object and PIF Object Reference Classes
    • The Value Declaration Class
    • The Value Definition Class
    • The Attribute Class
    • The Grid Classes
    • The Point List Classes
    • Unstructured Grid Element Representation
  • 7.1.2 Unstructured Grid Reading and Writing
  • 7.1.3 Generic Interpolation
  • 7.1.4 The KIRKPATRICK Point Location Method
    • Retriangulation
    • Efficiency Considerations
    • Applicability for Higher Dimensions
  • 7.1.5 A Practical GRS Example - The MINIMOS Wrapper
• 7.2 Other High-Level Libraries
  • 7.2.1 GAS
  • 7.2.2 G2S
  • 7.2.3 MAT
  • 7.2.4 CLS