Subject: comp.graphics.rendering.raytracing FAQ (part 2/2)
Supersedes: <rayfaq.2_827739673@ds2.acs.ucalgary.ca>
Date: 4 Apr 1996 16:10:41 GMT
References: <rayfaq.1_828634510@ds2.acs.ucalgary.ca>
Summary: Answers to Frequently Asked Questions about raytracing software
         on comp.graphics.rendering.raytracing

Posting-Frequency: every 10 days


This is part 2 of the comp.graphics.rendering.raytracing Frequently
Asked Questions list. The latest version of the FAQ is available via
anonymous WWW at:

http://www.cis.ohio-state.edu/hypertext/faq/bngusenet/top.html

under comp->graphics->rendering->raytracing.  It is also available via
anonymous ftp at:

ftp://rtfm.mit.edu/pub/usenet/news.answers/graphics/raytrace-faq/

If you only have email, you can get it by sending email to:

<mail-server@rtfm.mit.edu>

with both

"send usenet/news.answers/graphics/raytrace-faq/part1" and
"send usenet/news.answers/graphics/raytrace-faq/part2"

in the body of the message (without the quotes).

  (C) Copyright 1994 Andy Wardley <abw@peritas.demon.co.uk>
  (C) Copyright 1995, 1996 Andreas Dilger <adilger@enel.ucalgary.ca>

------------------------------

Subject: 4 - Utilities and Other Software

------------------------------

Subject 4.1 - Image Display/Conversion Programs

  * DISP - an excellent viewing and post-processing utility for DOS.
    Available on simtel and mirrors.

  * IMAGEMAGICK - An X-Windows based image display program (source
    distribution), that also allows simple editing of images, such as
    color modification, scaling, rotating, text annotation, etc.  PNG
    format images are now supported by ImageMagick.  Available at:
    ftp://harbor.ecn.purdue.edu/pub/imagemagick.tar.gz
    http://www.wizards.dupont.com/cristy/ImageMagick.html
    (Cristy, 1995)

  * NEOPAINT - A useful DOS shareware paint package (registration US
    $45) for creating images, height fields, etc, or just touching up
    finished artwork.  Available from wuarchive and mirrors.

  * NETPBM - A collection of command-line utilities for most platforms
    (source distribution).  Executables available for most other
    platforms like DOS, OS/2, Linux, and others.  NetPBM utilities
    convert practically any format to any other by using a common
    intermediate file format, as well as allowing quantization,
    cropping, combining, blur, and many other effects.  Available at:
    ftp://wuarchive.wustl.edu/graphics/graphics/packages/NetPBM/
    (Poskanzer et al., 1991-1994)

  * PICLAB - An excellent package for converting and post-processing
    images for DOS.  (Crocker, 1990)

  * QPV - The Quick Picture Viewer.  A great utility for displaying and
    converting images for DOS/Win systems.  Formerly QPEG, QPV has been
    improved, and has new features, such as the ability to read and
    write PNG format images.  (Fromme, 1995)

  * XV - An X-Windows based image display program (source distribution),
    with simple image editing facilities, such as color editing,
    scaling, rotation, and also filter effects for blurring, edge
    detection, and others.  A patch is available for XV 3.10 to support
    PNG images via libpng and libgz.  (Bradley, 1995)

------------------------------

Subject 4.2 - Format Conversion Utilities

  Much of the following sections area taken from Amanda Osbourne's
  <alo@northshore.ecosoft.com> "Raytrace Utilities for DOS (and Windows)"
  list.  All are IBM PC based unless otherwise specified.

  Various utilities for converting from one 3D file format to another:

  * 3DSPOV - Reads 3d studio mesh files. Writes out to Raw, POV-Ray
    (1 & 2), Vivid and Polyray.  (Anger & Bowermaster, 1993)

  * DEM2POV - This program (source distribution) converts US Geological
    Survey (USGS) Digital Elevation Maps (DEM) to the TGA format
    heightfields used by POV-Ray 2.2.  Includes a large DEM file of the
    region around the Grand Canyon.  (Kirby, 1995)

  * DXF2POV - DXF to POV-Ray 1 conversion program.
    (Collins, Wells, Farmer & Gibeson, 1992)

  * DXF2RAW - DXF to Raw conversion program.
    (Coy, Barber, Daigle & Shiffman, 1992)

  * DXF2V - DXF to Vivid conversion program.
    (Coy, Barber, Daigle & Shiffman, 1992)

  * DXF3DS - DXF to 3DS conversion program.  (Yost/Autodesk, 1991)

  * HUTIL101c - A set of utilities (source) for converting  between
    various POV-Ray heightfield formats (16-bit TGA, GIF, POT) as well
    as OCT and Matlab 32-bit MAT files.  In addition, it can combine
    heightfields using arithmetic operators, join them together, scale,
    and create spherical and cylindrical heightfields with triangle
    meshes.  (Beale, 1995)

  * MRYPLY - Converts Moray files to PolyRay files.

  * OBJ2ASC2 - Wavefront object to 3d studio ascii converter.
    (Knight, 1993)

  * RAW2PV - Excellent utility that allows the user to adjust the
    level of smoothing to apply to raw data as it is translated to
    POV-Ray (1 & 2.x), Polyray or Vivid 2. It can also add a camera
    and light to the scene, making things fairly easy for the novice
    user.  (Anger, 1993)

  * RAYL210 - Helpful utility to convert uLathe (an object creator
    program for windows) files to RAW, POV-Ray 1 & 2.x or Vivid 2
    format.  (Koehler, 1993)

  * TDDD2ASC - TDDD (Imagine) to 3D studio ascii file converter.
    (Knight, 1993)

  * WC2POV - Although wcvt2pov (Windows) started out converting 3D file
    formats to POV-Ray, wcvt2pov has become a generic 3D file format
    conversion utility, with support for importing 3d studio, Wavefront,
    NFF, DXF, TrueType Fonts, RAW triangles and some other formats, and
    exporting 3ds, asc, POV-Ray, NFF, DXF, VRML, Wavefront, Open GL 'C'
    code fragments, RAW triangles, and some other formats.  (Rule, 1995)

------------------------------

Subject 4.3 - Creation Creators

  Utilities to aid in the creation of ray tacing objects:

  * BOXER - Object generator for POV-Ray 1 (makes things like bathroom
    tiles and such based upon user input).  (Miller, 1993)

  * BRANCH - Tree creator for POV-Ray 1. (Weller, 1992)

  * CHAIN - Generates interlocking chain links for POV-Ray 1.0.
    (Koehler, 1992)

  * CM - CircleMaster utility for working with quadric spheres and
    ellipsoids; writes output to POV-Ray 1.0. (Brown, 1992)

  * COIL - Creates coiled objects for POV-Ray 1.0. (Kirby, 1992)

  * COILV - Creates coiled objects for Vivid 2. (Kirby & Cox, 1992)

  * CTDS - Connects a series of xyz dot coordinates. Though this may
    not sound like much, this is an extremely helpful utility.
    Supports POV-Ray, Vivid and Polyray. (Brown, 1993)

  * FORM - All sorts of shapes can be generated with this program.
    Form files consist of both shapes and commands (like twistx and
    bend) and output may be POV-Ray 1, 2 or .plg. Interesting program,
    complementary to LPARSER.  (Rowbottom, 1993)

  * FRACTINT - The ultimate fractals generator for DOS, X-windows source
    code, and distributed with the Linux Slackware games disks.  Great
    for creating height fields, colour maps, viewing gifs or just
    creating fractals.  (The Stone Soup Group, 1990-95)

  * FRGEN - Fractal Landscape (and other shapes too) Generator.
    Though the program supports Vivid and POV-Ray 1 & 2 directly, by
    selecting raw output you can smooth triangles out with RAW2POV to
    create nice hills and dales. (Anger, 1993)

  * GEODOME - Utility for generating geodesic domes.  Output to
    POV-Ray 2.x format as either facets or a mesh of pipes and joints.
    IBM PC executable, with source included. (Wardley, 1994)

  * GFORGE - Graphical Fractal Forgery (source, DOS exe).  Generates
    16-bit heightfields for POV-Ray, using a high-quality algorithm: the
    IFFT of 1/f noise.  File formats include PGM, PNG, POV TGA
    heightfield, and Matlab bin.  Several parameters give you control
    over the appearance of the output, which can range from sand to
    hills to mountains.  Useful also for 2D textures; the image always
    tiles perfectly.  Now also supports craters.  Source is available.
    (Beale, 1995)

  * LPARSER - L-system creator and mutator. This program is
    particularly strong in the creation of organic looking forms. Many
    example data files are included with the program.  The language of
    l-systems is not intuitive but the results can be truly stunning.
    Outputs to DXF (both R12 and 3D faces), POV-Ray 2.x, RAW and
    Renderstar VOL.  A wire-frame viewer that reads .3DS, .RAW,
    Fractint .RAY, ARE-24 .POL and Lparser/Renderstar .VOL files is
    included.  (Lapre, 1993)

  * LV20POVID - Newer and more powerful than LV2POV, this program
    reads an lviewer info file and generates data files in POV-Ray
    (1 & 2.x) and Vivid formats. The program's main strength lies in
    landscape generation. (van der Mark, 1993)

  * TRMK - Terrain Maker (DOS) uses a triangle midpoint subdivision
    algorithm to generate a variety of GIF heightfields.
    (Jorgensen, 1995)

  * PLANT - Fractal plant generator. Outputs supported are POV-Ray
    (1 & 2), Polyray and CTDS (Connect the dots smoother).
    (Bryerton, 1993)

  * SUDS - Random positioning of lots of spheres (or other objects)
    based on a variety of selections. (Farmer, Wegner & Schwan, 1994)

  * TORPATCH - This program creates a rope/wire object that passes
    smoothly through supplied points out of a series of clipped tori.
    Available as DOS EXE, and Turbo Pascal or C source.  Can also
    create a random tangle of wires. (Mackey & Beddes, 1996)

  * TWISTER - Utility that will create spirals, coils, etc., of
    blobs, cubes or sphere.  IBM PC executable with source, output to
    POV 2.x format.  (Wardley, 1994)

------------------------------

Subject 4.4 - Texture Editors

  * CMAP - Interactive color map creator for POV-Ray.
    (Lutz & Kretzschmar, 1993)

  * TCE - The color editor for POV-Ray 1. (Farmer, 1991)

  * TCEV - The color editor for Vivid. (Farmer, 1991)

  * TEXMAKE - Early version of a utility to assist in texture
    creation in POV-Ray 2.x. (Sigler, 1993)

  * TXMAG - Texture Magic is an interactive, 32-bit Windows based texture
    editor for POV-Ray 2.x, Assymetrix 3D F/X, and Autodesk 3D-Studio.
    ftp://ftp.povray.org/pub/povray/texture-editors/texture-magic/
    http://www.eskimo.com/~scott/povtext.html
    (Pultz, 1996)

------------------------------

Subject 4.5 - Animation

  * AERO - AERO is a X-Windows based physical simulation environment
    suitable for making complex, realistic animations.  Objects
    (including the camera) can be given properties like mass,
    velocity, and acceleration, constraints like springs and dampers
    can be specified between objects, and then AERO performs
    collision detection, position, and orientation calculations.
    Output is to POV-Ray 1.0 or 2.x scene files.
    (Keller, Stolz, Ziegler, Braunl, 1995)

  * AWKANI - AWK script to output POV-Ray animation data.
    (Farmer, 1992)

  * DTA - Dave's Targa Animator (DOS) converts .TGA and many other single
    image format frames into .FLI's and .FLC's. (Mason, 1995)

  * MPEG_ENCODE - MPEG_ENCODE (source distribution, also many
    executables) can take images in PPM and JPEG formats (as well
    as other formats, if a ...toppm converter exists) to produce
    a fully compliant  MPEG 1 animation.  It is possible to run
    the encoding on multiple processors. It is available in many
    locations (see 2 - FTP Sites, Bulletin Boards, etc.)
    (Rowe, et al, 1995)

  * MPEG_PLAY - MPEG_PLAY (source distribution, also many executables)
    displays MPEG 1 encoded animations on a large variety of systems.
    (Rowe, et al, 1995)

  * PPP - The POV and PolyRay Preprocessor allows scene files to be
    created with conditional statements, loops, math functions,
    vector math, and more to generate one or more scene files for
    animation and complex object creation. (Wind, 1995)

  * PVQUAN - PVQUAN (source) is a set of tools that allow you to create
    .FLI creations on many platforms including UNIX and DOS.  Source
    code is provided and includes a hosts of useful functions like
    quantisation, .GIF read, display, etc.

  * RAYSCENE - Set of animation utilities, not raytracer specific.
    (Jarik & Hassi, 1991)

  * RTAG - Ray Tracing Animation Generator (not raytracer specific).
    A powerful program with its own language which supports, amongst
    other things, spline path generation. (Sherrod, 1993)

  * SCEDA - SCEDA is a descendant of the SCED X-Windows modeller,
    with enhancements to allow generation of multiple scene files
    for an animation.  (See also 3 - Modelling Software)
    (McLaughlin & Chenney, 1996)

  * SP - Spline paths for animations.  Many output formats (POV-Ray,
    Vivid, Polyray, 3DV, Wire 3D) and acceleration and deceleration
    are supported as well. (Mason, 1992)

  * ZOOM - Interpolates steps between two positions for POV-Ray 1.0.
    (Brown, 1993)

------------------------------

Subject 4.6 - Miscellaneous Utilities

  * POVMODE.EL - A mode for emacs to handle POV-Ray syntax.  Available at:
    ftp://ftp.povray.org/pub/povray/old-incoming/misc/pov-mode.el

  * POVRAY TUTORIAL - The POV-Ray tutorial is a 100 page text tutorial
    that you can print out and read in the comfort of your own home.  It
    covers almost all of POV-Ray's features, including height fields,
    realistic spotlights, and image maps.  You can either jump to the
    section that interests you or follow through from the beginning to
    see the complete complex scene through to completion.  The tutorial
    is designed for beginners and more advanced artists alike. It is
    distributed free in Windows, Mac and postscript formats currently at:
    ftp://ftp.povray.org/pub/povray/old-incoming/utilities/pvt100.zip

------------------------------

Subject: 5 - Further Information and Resources

------------------------------

Subject 5.1 - On-line Resources

  * FAQs
    All of the FAQs in the USENET heirarchy that are posted to the
    news.answers newsgroup (as all FAQs should be) are archived at:
    ftp://rtfm.mit.edu/pub/usenet/news.answers/

    They are also converted to HTML format and made available at:
    http://www.cis.ohio-state.edu/hypertext/faq/bngusenet/top.html

+   For those people that are interested in learning about the internal
+   workings of a ray tracer, you should take a look at the newsgroup
+   comp.graphics.algorithms Frequently Asked Questions (FAQ).  This
+   document describes rotations, intersections, texture mapping, etc.

  * Ray Tracing News
    Eric Haines <erich@eye.com> has put together a phenomenal amount of
    information on ray tracing.  This he combines into his Ray Tracing
    News (RTNews).  They are a wealth of information and contain
    articles, sofware reviews and comparisons, book reviews and lists of
    everything and anything to do with ray tracing.  They are available
    from many sites in text and/or HTML format, including:
    ftp://ftp.princeton.edu/pub/Graphics/RTNews/
    http://wuarchive.wustl.edu/graphics/graphics/ray/RTNews/html/
    http://www.povray.org/rtn/

    Eric's ray tracing and radiosity bibliographies as well as an
    FTP list are available at:
    ftp://ftp.princeton.edu/pub/Graphics/Papers/

  * Ray Tracing Bibliogaphy
    Rick Speer <speer@crl.com> has also done a lot of work in bringing
    together articles on ray tracing.  He maintains a cross-indexed ray
    tracing bibliography of over 500 articles from 1968 to the present.
    These include papers from all Siggraph, Graphics Interface,
    Eurographics, CG International and Ausgraph proceedings.  All
    citations are keyworded and cross-indices are supplied by author and
    keyword.

    The bibliography is in the form of a 41 page postscript file which
    is held at many ftp sites as "speer.raytrace.bib.ps.Z":
    ftp://wuarchive.wustl.edu/graphics/graphics/bib/RT.BIB.Speer/
    ftp://karazm.math.uh.edu/pub/Graphics/
    ftp://nic.funet.fi/pub/sci/papers/graphics/

    Ian Grimstead <I.J.Grimstead@cm.cf.ac.uk> has also collected
    together a large collection of over 360 pages on-line of ray tracing
    papers.  It is accessible via the World-Wide Web and has links to
    other on-line papers and documentation at:
    http://www.cm.cf.ac.uk/Ray.Tracing/RT.Bibliography.html

    Ian also maintains a web page of links to other WWW ray tracing
    pages.  You can also add your own links to ray tracing pages that
    you maintain at:
    http://www.cm.cf.ac.uk/Ray.Tracing/

  * Ray Tracing Abstracts
    Tom Wilson <wilson@cs.ucf.edu> has collected over 300 abstracts from
    ray tracing related papers and books.  The collections is available
    as plain ascii, with Latex and troff formatting programs included.
    It is available as "rtabs.*" from many sites.

  * Graphics Resources List
    The Graphics Resources List contains a wealth of information on all
    sorts of computer graphics and visualization information.  It has
    info on mailing lists, plotting packages, ray-tracers, other
    rendering methods, etc.  It is available on comp.graphics,
    comp.answers or archived at various sites.  The official archive is
    ftp://rtfm.mit.edu/pub/usenet/news.answers/graphics/resources-list/part1
    ftp://rtfm.mit.edu/pub/usenet/news.answers/graphics/resources-list/part2
    ftp://rtfm.mit.edu/pub/usenet/news.answers/graphics/resources-list/part3
    ftp://rtfm.mit.edu/pub/usenet/news.answers/graphics/resources-list/part4
    ftp://rtfm.mit.edu/pub/usenet/news.answers/graphics/resources-list/part5
    ftp://rtfm.mit.edu/pub/usenet/news.answers/graphics/resources-list/part6

  * Paper Bank Project
    Juhana Kouhia <jk87377@cs.tut.fi> has collected together various
    technical papers in electronic form.  Contact him for more
    information.

------------------------------

Subject 5.2 - Other Newsgroups

  Note that because of news group reorganization, the previous
  raytracing news group, comp.graphics.raytracing, has disappeared.  The
  new group is comp.graphics.rendering.raytracing.

  Some other newsgroups that may be of interest to you are listed below.
  Most of these have FAQs of their own which are available at:
  ftp://rtfm.mit.edu/pub/usenet/news.answers/ [18.70.0.209]
  http://www.cis.ohio-state.edu/hypertext/faq/bngusenet/top.html

  - comp.graphics.algorithms
  - comp.graphics.animation
  - comp.graphics.misc
  - comp.graphics.apps.alias
  - comp.graphics.apps.lightwave
  - comp.graphics.apps.wavefront
  - comp.graphics.packages.3dstudio
  - comp.graphics.rendering.renderman
  - comp.graphics.visualization
  - alt.graphics.pixutils

------------------------------

Subject 5.3 - Books

  Title:      Ray Tracing Creations
  Authors:    Drew Wells and Chris Young
  Publisher:  The Waite Group
  Year:       1993
  ISBN:       1-878739-27-1

  This book has been written by Drew Wells and Chris Young, two of the
  original developers of POV-Ray, as a user and reference manual for
  POV-Ray.  Coming in at 573 pages, it's an excellent publication with
  literally hundreds of stunning colour and monochrome pictures.  The
  only drawback with the book is that it deals with POV-Ray version 1.0
  which is a little dated now that version 2.2 is out, but it is still a
  very worthwhile investment for any POV-Ray user.


  Title:      Ray Tracing Worlds with POV-Ray
  Authors:    Alexander Enzmann, Lutz Kretzschmar, and Chris Young
  Publisher:  The Waite Group
  Year:       1994
  ISBN:       1-878739-64-6

  Raytracing Worlds with POV-Ray is written with the intermediate to
  advanced POV-Ray user in mind.  This book comes with POVRay V2.2,
  Moray, and several additional tools for MS-DOS on diskette.  It
  assumes you have a basic knowledge of POVRay, which you can easily get
  by reading the POVRay documentation.  An review of the book is
  available at:
  http://www.povray.org/povzine/povzine1/raytrace.html


  Title:      Adventures in Ray Tracing
  Author:     Alfonso Hermida
  Publisher:  Que Corp.
  Year:       1993
  ISBN:       1-56529-555-2

  This book looks at Alexander Enzmann's ray tracer, Polyray
  (see 1 - Ray Tracing Software), and the author's own modelling system,
  POVCAD which runs under Microsoft Windows.  The two work well together.
  The content of the book is good and, as in the previous book, there
  are many excellent illustrations and pictures.

  There are a few errors in the book, but Alfonso has produced an
  errata list which is available from:
  ftp://wuarchive.wustl.edu/graphics/graphics/books/erratas/


  Title:      Photorealism and Ray Tracing in C
  Authors:    Christopher Watkins, Stephen Coy, Mark Finlay
  Publisher:  M&T Books
  Year:       1993
  ISBN:       ????

  Provided with this book is source code for a ray tracer called Bob
  which is a subset of Stephen Coy's full-blown ray tracer, Vivid
  (see 1 - Ray Tracing Software).


  Title:      Making Movies on Your PC
  Authors:    David K. Mason and Alexander Enzmann
  Publisher:  The Waite Group
  Year:       1993
  ISBN:       1-878739-41-7

  Focusing on animation, this book is by David K. Mason, author of many
  utilities including DTA - Dave's Targa Animator, and Alexander
  Enzmann, author of Polyray.  These tools, and others, are used to show
  how animations can be created on a PC.  It's a 210 page book that is
  laid out well with ample illustrations.


  Title:      An Introduction to Ray Tracing
  Authors:    Andrew Glassner (ed)
  Publisher:  Academic Press
  Year:       1989
  ISBN:       1-12-286160-4

  An Introduction to Ray Tracing has its main focus on the programming
  techniques, implementation, and theoretical concepts in writing a ray
  tracer.  It has been described as one of the two required books for
  ray tracing programmers (the other being Object-Oriented Ray Tracing
  in C++ by Nicholas Wilt) .  It contains chapters from many of the
  pioneers of ray tracing.  Eratta is available at:
  http://wuarchive.wustl.edu/graphics/graphics/books/erratas/IntroToRT


  Title:      Object-Oriented Ray Tracing in C++
  Author:     Nicholas Wilt
  Publisher:  John Wiley & Sons
  Year:       1993
  ISBN:       0471-304-158
  US Price:   $36.95

  This book takes the reader through many issues involved with the
  development of a ray tracer in C++.  The last section of the book
  deals with OORT, a class library for ray tracing.  It does not
  implement any input language or user interface but uses C++ calls to
  the library.  This is intuitive, due to the nature of C++, and
  extremely powerful as all the normal constructs of C/C++ such as
  loops, conditionals, etc., are available.

  It's definately a programmer's book and some knowledge of graphics
  programming is assumed.  Because of this, the nature of the book is
  quite technical and can be hard going.  Eric Haines sums it up well:

  "If you want to make pretty pictures, get POV, Polyray, Rayshade, etc.
  If you want to look at some nice C++ code for a vector & matrix
  library, etc, check this code out."

  The code is available from:
  ftp://wuarchive.wustl.edu/graphic/graphics/ray/
  ftp://ftp.funet.fi/pub/graphics/packages/ray-tracing/oort/

------------------------------

Subject 5.4 - Image Libraries

  The POV-Ray home site has a good collection of ray traced images.
  The site maintains a "Hall of Fame" for outstanding images created
  with POV-Ray:
  ftp://ftp.povray.org/pub/povray/Hall-Of-Fame/
  http://www.povray.org/hof/

  The archive of images submitted to the monthly ray-tracing competition
  held each month on comp.graphics.rendering.raytracing is also housed
  at ftp.povray.org.  Have a look at:
  ftp://ftp.povray.org/pub/competition/
  http://www.povray.org/competition/

  The Rayshade home page also has an amazing collection of images made
  with this renderer and some custom additions at:
  http://www-graphics.stanford.edu/~cek/rayshade/gallery/gallery.html

------------------------------

Subject 5.5 - Texture Libraries

+ There are a couple of initiatives under way to create a database of
+ POV-Ray textures.  People who have any textures at all from POV-Ray
+ are encouraged to send textures to the maintainers of the archives
+ so that everyone can benefit from the time you spent on creating the
+ textures.  A searchable index is available at:
+ http://nlic2.questint.com/texture/home.html

+ An independent library is available at:
+ http://www.informatik.tu-cottbus.de/~rs/povray/tex_lib_eng.html
+ http://www.informatik.tu-cottbus.de/~rs/povray/tex_lib.html [German]

  There is a library of building related textures (bricks, stone, etc.),
  for use as image maps at:
  ftp://wuarchive.wustl.edu/packages/architec/Textures/

------------------------------

Subject: 6 - Frequently Asked Questions

Now that you've been blasted with lists of FTP sites, utilitites,
software, books, etc., etc., the only questions you could possibly have
left to ask are those that...erm...aren't about FTP sites, utilities,
software or books, I suppose.  So this section attempts to answer all
the other questions that don't fit in above.

------------------------------

Subject 6.1 - "Who is..."

  This section looks at some of the ray tracing artists and people who
  are particularly well known for their work, be it images or software.
  The list is in strict alphabetical order as I don't fancy the task of
  trying be subjective about who's pictures are better than who's.

  A VERY IMPORTANT POINT: A lot of these people have to pay for their
  Email and 'net access.  DO NOT send them large images or other posts
  without checking with them first.  Certain members of the POV team
  have recently had some pretty hideous costs (like $30 for 1 mail item)
  because of this.  (Was that OK, Dan?)

  * Truman Brown
    Truman Brown <71477.221@compuserve.com> is particularly well known
    for his "woild" series of images.  He is a self-confessed "Obsessed
    Programmer / Trace-aholic" and has written a range of very useful
    utilities, including Connect The Dots Smoother (CTDS), Circle Master
    (CM) and its companion, HYPE.

    He has an understanding wife but his kids wish he didn't hog the PC
    so much.  His utilities are available from most FTP sites and you
    can check out some of his images at:
    ftp://ftp.povray.org/pub/povray/Hall-Of-Fame/
    http://www.povray.org/hof/

  * Dan Farmer
    One of the original POV-Ray development team, Dan has created some
    amazing images including the stunning "frosty.gif".  Dan explains
    how he did it:

   "The image was done in POV-Ray.  It's really quite simple.  The face
    is a freely available dataset produced by Mira Imaging... I'm sure
    it exists on the net somewhere.  The fractal shape is done with
    Fractint, using the 16 bit continuous potential features.  It's an
    inverted Mandelbrot set.  The silver texture is Silver1 in
    textures.inc.  The sky is the usual bozo, but it's mapped onto a
    plane, not a sphere.  Floor is an imagemapped plane.  That's all
    there is to it!"

    Frosty's at ftp://ftp.povray.org/pub/povray/Hall-Of-Fame/frosty.gif
    The Mira dataset ftp://ftp.povray.org/pub/povray/scenes/mirpov.zip

    Unfortunately, Dan rarely releases his source code any more due to
    certain unscrupulous sorts using his images for commercial purposes
    without payment or even permission.  Luckily, he has made the scene
    file for this image available on the POV-Ray CD-ROM which is also
    available online (see 1 - Ray Tracing Software).

    Dan is often around on the group and is very unselfish in spending
    time answering questions.  <70703.1632@compuserve.com>

  * Eric Haines
    Eric A. Haines <erich@eye.com> has probably done as much as anyone
    to make ray-tracing as understandable and accessible as it
    currently is.  His many, many hours compiling the Ray Tracing News
    helped lots of people understand and develop ray tracing software,
    as well as serve as a forum for discussion between those interested
    in the art.  (See 5 - Further Information and Resources).

  * Mike Miller
    If you ever need inspiration to see what can be done using POV-Ray,
    a piece of graph paper and a pencil, then look at some of Mike
    Miller's <70353.100@compuserve.com> images.  His pictures never fail
    to impress and he has undoubtedly produced some of the best pictures
    ever created with POV-Ray.  Mike created many of the demo scenes
    that come with POV-Ray and he is responsible for the excellent
    textures in "stones.inc".

    The cover story of the January 1994 IEEE Computer Graphics and
    Applications is entitled "Mike Miller's Many Hats" and looks at his
    work and includes many of his pictures.

    You can find his images and scene files on many sites.  A good one
    to start with is ftp://ftp.povray.org/pub/povray/Hall-Of-Fame/ or
    ftp://ftp.povray.org/pub/povray/images/.

    Particular ones to look out for are benz9.jpg (model of a 1928
    Mercedes Benz), camera.jpg, bug1.gif, etc., etc., the list goes on.

  * Ken Musgrave
    Ken Musgrave <musgrave@seas.gwu.edu> was called "the first true
    fractal-based artist" by Benoit Mandelbrot, the father of fractals.
    His work shows the artistic side of what can be done with
    mathematics and inspiration.  Many have seen his image "Blessed
    State" inside the cover of "Computer Graphics, Principles and
    Practice" by Foley & van Dam, the authoratative computer graphics
    book.  He has an excellent exhibit of his works available on the
    WWW at:

    http://www.seas.gwu.edu/faculty/musgrave/art_gallery.html

    Ken is currently applying his skills to creating an entire world
    model with algorithmic principles.

------------------------------

Subject 6.2 - "This picture doesn't trace."

  I know it might sound a bit obvious, but have you read the error
  message and tried to understand it?  Did you look in the manual?
  Still nothing?  I know I sound cynical, but it's not uncommon for
  people to have something go wrong and then post straight to the 'net
  without even *trying* to figure out what went wrong.  A little
  patience and thought will solve the problem a lot quicker.

  Here's some common problems:

  * POV-Ray versions
    A lot of people get fooled when trying to trace old POV-Ray code
    with a new version.  Use the -MV1.0 option or use #version in the
    code to get the parser to treat it as old code.  You may find that
    you have to change any references to "shapes.inc" to "shapes.old".

    The POV-Ray docs can help you out here.  What do you mean "I haven't
    got the docs"?  Go get them.  (See 1 - Ray Tracing Software)

  * Include files
    Have you checked that you've #included any include files that your
    scene requires?  Include files tend to define colours, textures or
    objects that your scene may use.  Make sure you've told the ray tracer
    where to look for include files.  For example, POV-Ray uses the -L
    option to specify the directory where include files are,  eg.

      -L/home/adilger/povray/include

    The POV-Ray docs can help you out here.  What do you mean "I haven't
    got the docs"?  Go get them.  The same applies if you haven't actually
    got the files (see 2 - FTP Sites, Web Sites, Bulletin Boards, etc.)

------------------------------

Subject 6.3 - "I traced my picture, but I can't see anything."

  If the picture is completely dark, there are several things you can check:

  * Have you added any light sources?

  * Are the light sources blocked by anything?  (This is a favourite of
    mine - I put in a large sphere for the sky and then add or move lights
    *outside* the sky sphere.  Where did the lights go?)

  * Where are you looking?  Are you sure your camera isn't inside an object?

  * Have you applied textures to your objects.  If you haven't, you might
    find that your ray tracer defaults your object to be black.

  Have you actually put anything into the picture?  This isn't as silly
  as it sounds.  If you #declare on object (POV-Ray, again) like this:

    #declare my_object=
    union {
      sphere { <0, 0, 0> 1 }
      cylinder { <-2, 0, 0> <2, 0, 0> 0.5 }
    }

  Then you have just told the ray tracer that when you refer to
  "my_object", you actually mean a union of a sphere and a cylinder as
  shown.  To use the object, you must explicitly put it in:

    object { my_object }

------------------------------

Subject 6.4 - "I traced my picture, but the output is garbage."

  Did you specify the correct output file format?  Most ray-tracers have
  several options for output file formats.  If you haven't explicitly
  specified the output format, there's a good chance it's not what you
  want it to be.  Also note that using a file name with an extension
  (like .TGA) does not necessarily mean this is the format of image.
+ This is a common mistake with POV-Ray 2.2 for UNIX which uses an
+ obscure output format by default.  Also, if you don't compile in the
+ URT support for Rayshade, you will get MTV format output files.  What
+ is MTV you ask?  It's one of the very early publicly available ray
+ tracers, written by Mark Terrence VandeWettering, now with Pixar.

  Some image display programs use the file extension to determineand the
  file contents, so if you call the file output.tga, and it's actually a
  PNG image, your display program may complain that the TGA file is
+ corrupted.  This is especially a problem with TGA files, since they
+ do not start with a "magic number", and this makes file identification
+ difficult.

------------------------------

Subject 6.5 - "How can I view these pictures?"

  If you're using UNIX, you can use XV which is available as a source
  distribution from many sites, or ImageMagick, again available on many
  sites.  It should be noted that XV v3.00, which is installed at some
  sites, does not display TGA files, although XV v3.10 and ImageMagick
  do.

  If XV and/or ImageMagick do not support a particular image format you
  have, it probably doesn't actually exist :-).  However, if you need to
  handle large numbers of images in batch form, or if you don't have an
  X windows display and you want to manipulate images (but not
  necessarily view them), chances are that the netpbm package is what
  you need.  Netpbm is a command line utility, and can converting images
  from practically any format to any other, but it does not display the
  images themselves.

  If you're on a PC and using DOS, you'll probably want to get either
  QPV or PICLAB to do the displaying.  For Windows users, lview seems to
  be a popular display/editing program, and for OS/2 there is PMJpeg,
  which is an OS/2 port of lview.  There are kegs-o-megs of PC image
  viewers at most ftp sites, so take your time and find one you like.

  These packages are available in countless locations on the Internet
  (see 4 - Utilities and Other Software).

------------------------------

Subject 6.6 - "Rotating/scaling this object doesn't work properly."

  With most ray tracers, rotating on object in a given direction rotates
  it around the axis *not* around its own centre.  If your object is
  centred on the X axis and you rotate it in the X direction, it will
  spin.  However, if it is some distance from the axis and you rotate
  it, it will "orbit" the X axis, tracing a circle with a radius equal
  to the distance of the object from the axis.

  Confused?  Think of the Earth spinning on it's axis.  It doesn't go
  anywhere because it is centred on its axis (ignoring rotation around
  the Sun).  The moon, however is some distance from the Earth's axis
  and as it rotates around that axis, it travels through space, orbiting
  the Earth.

  To work out which way something will move, you need to know if your
  ray tracer uses a left or a right handed co-ordinate system.  POV-Ray,
  for example, uses a left handed system.  To work out which way an
  object will turn, point your thumb in the positive direction of the
  axis you're rotating in and the way you fingers curl indicate the
  direction of positive rotation.  The hand you use to do this depends
  on your ray tracer; left-handed, use left hand, right handed, use
  right.

  The same thing goes for scaling.  If your object is already some
  distance away from the origin, that distance will also get scaled.
  For example, if you have a sphere 2 units away from the origin, with a
  radius of 1 and you scale it by 2, the radius will now be 2 *and* the
  distance from the origin will be 4.

------------------------------

Subject 6.7 - "Where can I find model data for..."

  The former Avalon site has been closed down, and the Avalon model site
  has been moved to Viewpoint, a commercial model vendor, as of 07/95.
  It is the promise of Viewpoint that the Avalon data remain freely
  available to all.  Avalon is now located at:
  ftp://avalon.viewpoint.com/avalon/ or
  http://www.viewpoint.com/avalon.html or
  ftp://ftp.povray.org/pub/mirrors/avalon/ is a mirror.

  Avalon is probably the best site you'll find for free 3D model data.
  However, the home page at Viewpoint also has pointers to their free
  and commercial models if you can't find what you need at Avalon.
  Another commercial model vendor on the net is MeshMart at:
  http://cedar.cic.net/~rtilmann/mm/

  (See also 2 - FTP Sites, Web Sites, Bulletin Boards, etc.)


------------------------------

Subject 6.8 - "Can I post binaries/images to this group?"

  In a word, NO.  The group is part of the comp.graphics hierarchy which
  should be, and is, strictly non-binary.  The reason for this is that
  uuencoded binaries tend to be very large.  By restricting binary
  postings to the comp.binaries and alt.binaries hierachies, those sites
  who do not want to carry large volume groups can easily ignore
  anything under these two streams.

  Remember that most sites pay to transfer and store news and if they
  find that comp.graphics.rendering.raytracing is getting too expensive,
  they can just stop carrying it.  That is their right and priviledge.
  Also remember that many individuals download this group via modems and
  pay for every byte.  They tend to get a bit annoyed when they have to
  fork out lots of money to download stuff they might not even want.

  But what if you're really desperate to share with us your latest ray
  tracing you've done depicting a mutant star camel exploding in a super
  nova while naked dancers melt into a checkered floor? (the checkered
  floor always turns up sooner or later).  Great!  I'm sure we'd love to
  see it, you should post it to news:alt.binaries.pictures.misc or upload
  it to ftp://ftp.povray.org/pub/povray/incoming/images/.  If you're
  posting it you should remember to uuencode it and split it into small
  (less than 64k) parts.  Make sure to use an informative title like:

    RAY TRACING: MUTANT.GIF: mutant star camel scene, part 1 of 6

  and include a text posting (part 0 of n) that describes the picture,
  states what format it's in (.gif, .jpg, etc.), what size it is, how
  many colours, and anything else you want to mention.  The more you
  put, the better.

  You can then post a message to news:comp.graphics.rendering.raytracing,
  along with a few lines saying "I've just posted this image to
  alt.binaries.pictures.misc".  BTW, ray tracing pictures generally get
  a good response over in a.b.p.m and you'll often see request for them
  in news:alt.binaries.pictures.d (the discussion group).

  If it's a utility you're posting, it should go to alt.binaries.misc
  instead of news:alt.binaries.pictures.misc, but the same process applies.

  The other alternative is to upload the picture or utility to an ftp
  site and use news:comp.graphics.rendering.raytracing to announce it in
  the same way.

------------------------------

Subject 6.9 - "What does this mean..."

  Some ray tracing and related terms you might come across:

  * CSG (Constructive Solid Geometry) - A term describing ways in which
    you can build up complex shapes from simple primitives like cubes,
    speres, and cylinders.  By combining the primitives in different
    ways, namely adding them together (union), taking one away from the
    other (difference) or getting the part where they intersect
    (intersection) you can make small building blocks, which can in turn
    be used to make more complex CSG objects.

  * Height Field - A height field can be thought of as a 3 dimensional
    bar graph.  It is a grid of data where the value at any point
    corresponds to the "altitude" of that point.  Height fields are
    typically stored as images with the lighter areas being higher, and
    the darker areas lower.  Heightfields are usually used for flat
    surfaces, but can also be wrapped around cylinders and spheres in
    some software packages.

  * Radiosity - Most ray-tracers use an empirical lighting model - that
    is the parameters specified for lights and objects do not really
    correspond to physical properties, but are selected to make things
    look good.  Radiosity calculates the reflections and lighting
    between all objects in the scene, and gives a more realistic
    rendering of the scene.  This method is very good at representing
    the diffuse lighting in a scene, while ray-tracing is better at
    handling the reflection.  In some renderers, both techniques are
    used to give spectacular results.  Needless to say, radiosity is
    even more computationally complex than ray-tracing.

------------------------------

Subject 6.10 - "What is the difference between rendering and ray-tracing?"

  Ray tracing *is* rendering.  But then so is z-buffer rendering,
  scanline rendering, etc.  Ray tracing is just another algorithm used
  to render (i.e. "paint") pictures.

------------------------------

Subject 6.11 - "When will POV-Ray 3.0 come out?"

| At long last, POV 3.0 is nearly with us.  There is currently a public
| beta test program underway.  The POV-Team have made binaries available
| for the MS-DOS and Macintosh platforms, and are expected to also
| release a 32-bit Windows and Linux binary during the beta test phase.
| These beta versions contain expiration timers, but newer beta binaries
| will be released until the Team releases the source code.  It is
| unlikely that there will be beta binaries for other UNIX and non-UNIX
| platforms.  The POV-Team asks that you do not ask them questions about
| how to use POV-Ray.  If you have a SPECIFIC BUG REPORT, you are asked
| to contact the POV-Team leader, Chris Young.  For more information, see:
| http://www.povray.org/cc/beta-announce/povindex.htm
| ftp://ftp.povray.org/pub/povray/Official/3.0-beta/

------------------------------

Subject 6.12 - "Where are the .inc files for POV-Ray?"

  The .inc files in question (textures.inc and colors.inc) are included
  in the documentation files, which should be at the same location as
  the POV-Ray source or executable files. These files were deliberately
  left out of the other packages so you would HAVE to get the
  documentation.  This will save everybody from answering a lot of
  questions later.  Read the documentation.  It is good.  How do you
  propose to create anything without the documentation?
  (See 2 - FTP Sites, Web Sites, Bulletin Boards, etc.)

------------------------------

Subject: 7 - Roll the Credits

Special thanks go to Eric Haines <erich@eye.com> for his help and the
wealth of information he has provided both directly and in Ray Tracing
News, FTP lists, etc.

Thanks also to all those people who maintain other lists,
bibliographies, FTP sites, or have provided me with specific
information, told me where to look, produced mini-faqs (thanks John) or
have just posted answers to the group:

  John Beale <beale@leland.Stanford.edu>
  Nick Fotis <nfotis@theseas.ntua.gr>
  Jim Grimes <jimg@bongo.jpl.nasa.gov>
  Ian Grimstead <I.J.Grimstead@cm.cf.ac.uk>
  Eric Haines <erich@eye.com>
  Laszlo Herczeg <las@light-house@whome.planix.com>
  Chris W. Morris <cwm@hopper.itc.virginia.edu
  Frank Neumann <Frank.Neumann@arbi.informatik.uni-oldenburg.de>
  Bjorn-Kare Nilssen <bjoernk@oslonett.no>
  George Kyriazis <kyriazis@mistral.esd.sgi.com>
  Daniel Palermo <palermo@crhc.uiuc.edu>
  Harry Rowe <Harry.Rowe@wedowind.meaddata.com>
  Heinz Schuller <heinzs@delphi.com>
  Rick Speer <speer@crl.com>
  Greg Ward  <greg@pink.lbl.gov>
  Andy Wardley <abw@peritas.demon.co.uk>
  Oliver Weyand <chbrin3@nyx.uni-konstanz.de>
  Marius Watz <mariusw@ifi.uio.no>

Finally, some king-size thanks to all those people out there who have
developed, and continue to do so, all the ray tracing software and
utilities that keep us so occupied.  Wives, girlfriends and children may
disagree on this point, but thanks anyway.

Special awards in this category go to Dan Farmer
<70703.1632@compuserve.com> who wins the Award for "Not-Only-Doing-All-
His-POV-Team-Stuff-But-Also-Answering-Lots-of-Questions-And-Being-An-All-
Round-Mr.-Nice-Guy", and Chris Cason <Chris.Cason@oaks.com.au> who gets
the coveted "Also-Does-His-POV-Bit-Especially-Being-Admin-of-the-POV-Site-
And-Answering-Questions-As- Well-And-Making-the-POV-Ray-CD-Too".

Sorry if I've forgotten anyone.  Thanks anyway.

------------------------------

Subject: Epilogue

You may have noticed one or two gaps in the FAQ or spotted a glaring
error, or just thought of something that I really should have mentioned.
If that's the case and you can provide some info or corrections, then
let me know and sort it out.

Well here you are at the end of the document, and your trace is still
only half done.  You've probably got time to walk the dog before it's
finished...

Happy Tracing.

-- 
Andreas Dilger   University of Calgary  \"If a man ate a pound of pasta and
(403) 220-8792   Micronet Research Group \ a pound of antipasto, would they
Dept of Electrical & Computer Engineering \   cancel out, leaving him still
http://www-mddsp.enel.ucalgary.ca/People/adilger/       hungry?" -- Dogbert
