A three dimensional wire frame graphics system

ABSTRACT

This paper describes the design and implementation of an APL based three dimensional graphics system. The system is composed of several functions which are grouped into individual modules such as modelling functions, viewing functions, transformation functions, view aid functions, special view functions, text manipulating functions and several other helpful functions. The task of obtaining a perspective view from an arbitrary observer position has been simplified - all that is needed is the (x, y, z) co-ordinates of the eye position and the 3-D description of the object(s). One can obtain parallel, perspective and oblique projections using this system. Functions are provided to obtain a movie type strip chart of perspective views of an object as the eye position moves slowly along a specified path. Several functions, such as plane sweep, surface revolution, are provided to simplify the task of generation of 3-D description of the objects. Many sample functions are written to generate various types of 3-D objects; an accompanying workspace contains these functions. The paper contains several illustrative examples.

REFERENCES

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INDEX TERMS

Classification:
  D. Software
  D.3 PROGRAMMING LANGUAGES
      D.3.2 Language Classifications

          Nouns: APL

  I. Computing Methodologies
  I.3 COMPUTER GRAPHICS
      I.3.4 Graphics Utilities
          Subjects: Software support

General Terms:
Design, Languages