﻿The attached •User Manual• consists of three chapters:

- the first one provides a brief theoretical introduction by 
  repeating some parts of the article

  Agoston Roth, 2019. Algorithm 992: An OpenGL- and C++-based 
  function library for curve and surface modeling in a large 
  class of extended Chebyshev spaces, 
  ACM Transactions on Mathematical Software, 
  Vol. 45, No. 1, Article 13, https://doi.org/10.1145/3284979

  (the proofs of our theoretical results are deliberately omitted);

- the entire implementation of the proposed function library is
  explained in the exhaustively commented listings of the second
  chapter, by using cross references to the theoretical parts 
  detailed in the first chapter;

- the last chapter provides several examples for creating and
  interactively manipulating EC space objects, B-curves and 
  B-surfaces (these examples are formulated in a general context, 
  while their special Qt-based implementations can be found in 
  the folder •../Src/03_Examples•).

If the reader is not interested in every aspect of the full
implementation details, the second chapter can be skipped. 
However, we suggest to study at least the pages •13--14• and 
•Fig. 2.1• of the current •User Manual• which outline the layout 
of the proposed function library and briefly detail only the 
most important data structures.



