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[Game.Programming].Academic - Graphics Gems (6 books source code)

C++ code augmenting the article
"C++ Vector and Matrix Algebra Routines"
by Jean-Francois Doue, [e-mail]
in "Graphics Gems IV", Academic Press, 1994


This directory contains a very basic ray-tracer, programmed to
demonstrate the advantage of using a C++ vector and matrix library
called algebra3. The library makes programs easier to write and to
debug.

This document briefly discusses the class hierarchy of the program and
the format of the description files which must be passed to it. An
appendix lists all the files in this directory and describes them
briefly.

CLASS HIERARCHY
---------------

         |---> Camera
         |
Object3D ----> Primitive ----> Sphere
         |               |
         |               |
         |               ----> Polyhedron
         ----> Light

Scene3D

The main program just creates a new Scene3D (a collection of
Object3Ds), parses it from a text description, and invokes the
Scene3D::rayTrace method. The Scene3D returns an array of 24 bits
pixels. It is up to the reader change the code so as to save the image
in a format appropriate to his/her machine (the program can compute the
images, but does not display them).

The ray-tracer is voluntarily very basic: it is only capable of
rendering spheres and concave polyhedrons, lit by point lights. It uses
Phong's reflection model, but is not recursive, does not do shadows,
light attenuation, textures, etc ...  What should be of interest about
the program is the way it is written, not what it is capable of.

FORMAT
------

3D scenes can be parsed from text representation. The text
representation is simply a list (in any order) of 3D objects (camera,
sphere, polyhedron and light). The parsing method is very crude and
does not check the accuracy of the description file thoroughly. The
exact syntax for each possible type of 3D objects is:

Camera:
 ______________________________________________________________
|                              |                               |
| text file                    | comments                      |
|______________________________|_______________________________|
|                              |                               |
|   camera                     | - keyword;                    |
|   | 0.0 0.5 4.0 |            | - position of the camera;     |
|   | 1.0   0.0   0.0   0.0 |  | - orientation of the camera;  |
|   | 0.0   1.0   0.0   0.0 |  |                               |
|   | 0.0   0.0   1.0   0.0 |  |                               |
|   | 0.0   0.0   0.0   1.0 |  |                               |
|   | 60.0 60.0 |              | - field of view (in degrees); |
|______________________________|_______________________________|

Sphere:
 ______________________________________________________________
|                              |                               |
|   text file                  | comments                      |
|______________________________|_______________________________|
|                              |                               |
|   sphere                     | - keyword;                    |
|   | 0.0 0.5 4.0 |            | - position of the sphere;     |
|   | 1.0   0.0   0.0   0.0 |  | - orientation of the sphere;  |
|   | 0.0   1.0   0.0   0.0 |  |                               |
|   | 0.0   0.0   1.0   0.0 |  |                               |
|   | 0.0   0.0   0.0   1.0 |  |                               |
|   | 0.9 1.0 1.0 |            | - color of the sphere;        |
|   | 0.1 0.48 0.7 20.0 |      | - phong coefficients;         |
|   2.0                        | - radius;                     |
|______________________________|_______________________________|

Polyhedron:
 ______________________________________________________________
|                              |                               |
| text file                    | comments                      |
|______________________________|_______________________________|
|                              |                               |
|   polyhedron                 | - keyword;                    |
|   | 0.0 0.5 4.0 |            | - position of the polyhedron; |
|   | 1.0   0.0   0.0   0.0 |  | - orientation of the          |
|   | 0.0   1.0   0.0   0.0 |  |   polyhedron;                 |
|   | 0.0   0.0   1.0   0.0 |  |                               |
|   | 0.0   0.0   0.0   1.0 |  |                               |
|   | 0.9 1.0 1.0 |            | - color of the polyhedron;    |
|   | 0.1 0.48 0.7 20.0 |      | - phong coefficients;         |
|   10                         | - number of vertices;         |
|   | -1.0 -1.0 -1.0 |         | - first vertex;               |
|   |  1.0 -1.0 -1.0 |         | - second vertex;              |
|       .......                |                               |
|   |  0.0  1.8  1.0 |         | - last vertex;                |
|   7                          | - number of facets;           |
|   5 0 3 8 2 1                | - first facet (number of      |
|                              |   vertices followed by the    |
|                              |   index of each vertex in the |
|                              |   facet);                     |
|   5 4 5 6 9 7                | - second facet;               |
|       .......                |                               |
|   4 0 4 7 3                  | - last facet;                 |
|______________________________|_______________________________|

Light:
 ______________________________________________________________
|                              |                               |
|   text file                  | comments                      |
|______________________________|_______________________________|
|                              |                               |
|   light                      | - keyword;                    |
|   | 0.0 0.5 4.0 |            | - position of the light;      |
|   | 1.0   0.0   0.0   0.0 |  | - orientation of the light;   |
|   | 0.0   1.0   0.0   0.0 |  |                               |
|   | 0.0   0.0   1.0   0.0 |  |                               |
|   | 0.0   0.0   0.0   1.0 |  |                               |
|   | 0.9 1.0 1.0 |            | - color of the light;         |
|______________________________|_______________________________|

Comment lines (starting with the '%' sign) can be inserted in the text
(between 3D objects only, not within the description of a 3D object
!!!).


APPENDIX
--------

Camera.c        // Implementation of the camera class
Camera.h        // Interface of the camera class
Light.c         // Implementation of the point light class
Light.h         // Interface of the point light class
Makefile        // Unix makefile
Object3D.c      // Implementation of the 3D object class
Object3D.h      // Interface of the 3D object class
Polyhedron.c    // Implementation of the concave polyhedron class
Polyhedron.h    // Interface of the concave polyhedron class
Primitive.c     // Implementation of the primitive class
Primitive.h     // Interface of the primitive class
README          // This file
Scene3D.c       // Implementation of the 3D scene class
Scene3D.h       // Interface of the 3D scene class
Sphere.c        // Implementation of the sphere class
Sphere.h        // Interface of the sphere class
algebra3.c      // The vector and matrix library
algebra3.h      // Include file of the vector and matrix library
main.c          // Main program
example.tiff    // A sample picture rendered with the program
example.data    // The script to render example.tiff
solver.c        // Math utilities by Jochen Schwarze (see Graphics Gems 1 for
solver.h        // more details)