Section 1
Introduction

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Note that this document is still in work and there may (and will) be some larger changes. Do not waste your time, money and paper to print this document!

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This document details the use of the Persistence of Vision(tm) Ray Tracer (POV-Ray(tm)). It is broken down into four parts: the installation guide, the tutorial guide, the reference guide and the appendix. The first part (see chapter "Program Description" chapter and "Quick Start" ) tells you where to get and how to install POV-Ray. It also gives a short introduction to ray-tracing. The tutorial explains step by step how to use the different features of POV-Ray (see chapter "Beginning Tutorial" ). The reference gives a complete description of all features available in POV-Ray by explaining all command line options (INI file keywords) and the scene description language (see chapter "POV-Ray Reference" , chapter "POV-Ray Options" and chapter "Scene Description Language" ). The appendix includes some tips and hints, suggested reading, contact addresses and legal information.

POV-Ray(tm) is based on DKBTrace 2.12 by David K. Buck and Aaron A. Collins.

Section 1.1
Notation

Throughout this document the following notation is used to mark keywords of the scene description language, command line options, INI file keywords and file names. 

  name  scene description keyword
  name  command line option
  name  INI file keyword
  name  file name
  name  Internet address, Usenet group

Section 2
Program Description

The Persistence of Vision(tm) Ray-Tracer creates three-dimensional, photo-realistic images using a rendering technique called ray-tracing. It reads in a text file containing information describing the objects and lighting in a scene and generates an image of that scene from the view point of a camera also described in the text file. Ray-tracing is not a fast process by any means, but it produces very high quality images with realistic reflections, shading, perspective and other effects.

Section 2.1
What is Ray-Tracing?

Ray-tracing is a rendering technique that calculates an image of a scene by shooting rays into the scene. The scene is build from shapes, light sources, a camera, materials, special features, etc.

For every pixel in the final image a viewing ray is shot into the scene and tested for intersection with any of the objects in the scene. Viewing rays originate from the viewer, represented by the camera, and pass through the viewing window (representing the final image).

Every time an object is hit, the color of the surface at that point is calculated. For this purpose the amount of light coming from any light source in the scene is determined to tell wether the surface point lies in shadow or not. If the surface is reflective or translucent new rays are set up and traced in order to determine the contribution of the reflected and refracted light to the final surface color.

Special features like interdiffuse reflection (radiosity), atmospheric effects and area lights make it necessary to shoot a lot of additional rays into the scene for every pixel.

Section 2.2
What is POV-Ray?

The Persistence of Vision(tm) Ray-Tracer was developed from DKBTrace 2.12 (written by David K. Buck and Aaron A. Collins) by a bunch of people, called the POV-Team(tm), in their spare time. The headquarters of the POV-Team is in the GRAPHDEV forum on CompuServe (see "Graphics Developer Forum on CompuServe" for more details).

The POV-Ray(tm) package includes detailed instructions on using the ray-tracer and creating scenes. Many stunning scenes are included with POV-Ray so you can start creating images immediately when you get the package. These scenes can be modified so you don't have to start from scratch.

In addition to the pre-defined scenes is a large library of predefined shapes and materials that you can use in your own scenes by just including the appropriate files and typing the name of the shape or material.

Here are some highlights of POV-Ray's features:

*Easy to use scene description language.
*Large library of stunning example scene files.
*Standard include files that pre-define many shapes, colors and textures.
*Very high quality output image files (up to 48-bit color).
*15 and 24 bit color display on IBM-PC's using appropriate hardware.
*Create landscapes using smoothed height fields.
*Spotlights, cylindrical lights and area lights for sophisticated lighting.
*Phong and specular highlighting for more realistic-looking surfaces.
*Interdiffuse reflection (radiosity) for more realistic lighting.
*Atmospheric effects like atmosphere, fog and rainbow.
*Halos to model effects like clouds, dust, fire and steam.
*Several image file output formats including Targa, PNG and PPM.
*Basic shape primitives such as ... spheres, boxes, quadrics, cylinders, cones, triangles and planes.
*Advanced shape primitives such as ... torii (donuts), hyperboloids, paraboloids, bezier patches, height fields (mountains), blobs, quartics, smooth triangles, text, fractals, superquadrics, surfaces of revolution, prisms, polygons, lathes and fractals.
*Shapes can easily be combined to create new complex shapes using Constructive Solid Geometry (CSG). POV-Ray supports unions, merges, intersections and differences.
*Objects are assigned materials called textures (a texture describes the coloring and surface properties of a shape).
*Built-in color and normal patterns: Agate, Bozo, Bumps, Checker, Crackle, Dents, Granite, Gradient, Hexagon, Leopard, Mandel, Marble, Onion, Quilted, Ripples, Spotted, Sprial, Radial, Waves, Wood, Wrinkles and image file mapping.
*Users can create their own textures or use pre-defined textures such as ... Brass, Chrome, Copper, Gold, Silver, Stone, Wood.
*Combine textures using layering of semi-transparent textures or tiles of textures or material map files.
*Display preview of image while computing (not available on all platforms).
*Halt rendering when part way through.
*Continue rendering a halted partial scene later.

Section 2.3
Which Version of POV-Ray should you use?

POV-Ray can be used under MS-Dos, Windows 3.x, 95 and NT; Apple Macintosh 68k and Power PC; Commodore Amiga; Linux, UNIX and other platforms.

The latest versions of the necessary files are available over CompuServe, Internet, America Online and several BBS's. See section "Where to Find POV-Ray Files" for more info.

Section 2.3.1
IBM-PC and Compatibles

Currently there are three different versions for the IBM-PC running under different operating systems (MS-Dos, Windows, Linux) as described below.

Section 2.3.1.1
MS-Dos

The MS-Dos version runs under Ms-Dos or as a dos application under Windows'95, Windows NT, Windows 3.1 or 3.11. It also runs under OS/2 and Warp.

Required hardware and software:

-A 386 or better CPU and at least 4 meg of RAM.
-About 6 meg disk space to install and 2-10 meg or more beyond that for working space.
-A text editor capable of editing plain ASCII text files. The EDIT program that comes with MS-Dos will work for moderate size files.
-Graphic file viewer capable of viewing GIF and perhaps TGA and PNG formats.

Required POV-Ray files:

-POVMSDOS.EXE - a self-extracting archive containing the program, sample scenes, standard include files and documentation in a hypertext help format with help viewer. This file may be split into smaller files for easier downloading. Check the directory of your download or ftp site to see if other files are needed.

Recommended:

-Pentium or 486dx or math co-processor for 386 or 486sx.
-8 meg or more RAM.
-SVGA display preferably with VESA interface and high color or true color ability.

Optional: The source code is not needed to use POV-Ray. It is provided for the curious and adventurous.

-POVMSD_S.ZIP - The C source code for POV-Ray for MS-Dos Contains generic parts and MS-Dos specific parts. It does not include sample scenes, standard include files and documentation so you should also get the executable archive as well
-A C compiler that can create 32-bit protected mode applications. We support Watcom 10.5a, Borland 4.52 with Dos Power Pack and limited graphics under DJGPP 1.12maint4. DJGPP 2.0 not supported.
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