### 2.1.5 The Early History of POV-Ray

You know you have been raytracing too long when ...
... You hear a name beginning with the letter K and wonder if it's David Buck's middle name.
  -- Alex McLeod

OK, here's a not-so brief history of POV-Ray (from the horse's mouth, so to speak):

Back in 1986 or so, I had an Amiga. A friend who also has an Amiga downloaded the C code for a raytracer for Unix from the Internet and brought it over. I thought it looked interesting and I ported it to the Amiga and wrote the drivers to display it with Amiga graphics. The program only rendered untextured spheres with a planar floor in black and white, but I was still impressed by it. I played with it a bit adding support for color, but I eventually decided that I could do a better job writing a raytracer from scratch, so I scrapped the C program and started my own - DKBTrace had begun.

I decided to start with general quadric surfaces since they could represent spheres, ellipsoids, cylinders, planes, and more. I worked out the ray-quadric intersection calculations and used some calculus to work out the surface normal to a quadric surface at a point. For the program structure, I decided to use an object-oriented style since I had learned Smalltalk at university and it fit nicely. To make modeling more flexible, I added CSG and procedural textures. In the end, I had an interesting little raytracer and I decided to release it as freeware since I was planning to return to university to start my Master's degree and didn't have time to develop a commercial raytracer. Besides, there were already commercial renders for the Amiga that had user interfaces (not just text files) and I felt I couldn't sell it as a commercial product. I called it DKBTrace and released it to local BBS'es and to the Internet.

DKBTrace was an Amiga-only program, but it attracted quite a lot of interest. I released several versions of it adding in new features, better primitives, more texturing options, etc. Eventually I released version 2.01.

Sometime around 1987 or 1988, I was contacted by Aaron Collins. He had found the C code for DKBTrace and ported it to the PC. He also added a Phong lighting model and a few more goodies. I was interested in what he had done, so I contacted him to see if he wanted to help develop a new version of the program. This one would be portable across more platforms (at university I had access to Unix workstations). We eventually came up with version 2.l2 which was the last version of DKBTrace ever released (1989).

While Aaron and I were working up to version 2.12, there was a group of people on CompuServe who were very excited about DKBTrace and were creating all sorts of neat scenes for it. They were also expressing frustration that Aaron and I weren't able to add new features into DKBTrace fast enough. They started talking about building a whole new raytracer from scratch that they could control and add the features they wanted. At that time, I was starting to pursue other areas and was starting to drift away from raytracing. So, I posted a message on CompuServe with the following offer: We could form a team to develop a new raytracer using DKBTrace as a base. I had three requirements for this team. The resulting code had to be freeware with the source code freely available, it had to remain portable between different platforms, and it had to have a different name than DKBTrace.

The name DKBTrace was, of course, based on my initials: David Kirk Buck (there's some little known trivia for you). With a package developed by a team of people, it was inappropriate to use my initials. I was also starting to drift away from raytracing (as I mentioned) and I didn't want people thinking that I was the head of the team forever. The name that was proposed was "Persistance Of Vision Raytracer" which was shortened to POV-Ray. It worked in three ways. It was the result of a persistent vision of the developers, it was a reference to the Salvador Dali work which depicted a distorted but realistic world, and the term "persistance of vision" in biology referred to the ability to see an image that was presented briefly - almost an after image.

In 1989, then, DKBTrace 2.12 was officially released and the POV-Ray project had begun. I worked with the team for a few years after that. I was responsible for the Amiga port among other things. Drew Wells was the project leader. Aaron Collins dropped out of the project around that time as well. Other early members included Chris Young, Steve Anger, Tim Wegner, Dan Farmer, Bill Pulver (IBM drivers), and Alexander Enzmann (quartics and cool math stuff). Chris Cason joined shortly after (my apologies if I left anyone out - lots of people were involved). The reference to Robert Skinner in the credits for POV-Ray was because we had a hard time finding a good noise function. In another raytracer, he had a great noise function written by Robert Skinner, so we asked for and received permission to use it in POV-Ray.

There was so much demand for us to release a new version that we created POV-Ray 0.5 and released it. It was basically an enhanced DKBTrace with a similar grammar but many more features. Eventually, we released POV-Ray 1.0 which had the new grammar and lots of new stuff. Drew dropped out later and Chris Young took over as project leader.

It was around that time that I started to drift away from the POV-Ray team. The project had momentum and could continue on without me. I was getting into different areas (physically based modeling and animation) and no longer had the time to continue with POV-Ray. Around the release of version 2.0, I left the project and the POV-Ray team developed it to its current state. Chris Cason is now the project leader.

Even though I'm no longer on the POV-Ray development team, I still like to follow its progress. I haven't built my own scene by hand for years now (although I occasionally use Moray). I still enjoy the one thing that drove me back in the DKBTrace days - I love seeing the works of other people who used my software. Even though I can no longer call POV-Ray "my software", I still enjoy admiring the artwork people create with it. I'm constantly amazed at what people can do. It was always the feedback from user community that drove me.

David Buck,
david [at] simberon.com
august 2001

#### 2.1.5.1 The Original Creation Message

    11906 S16/Raytraced Images
       07-Mar-91 18:56:37
    Sb: DKB Development
    Fm: David Buck 70521,1371
    To: All

    Greetings all.  This is my first posting to this group, so you'll
    have to excuse me if I make any mistakes in this post.

    Finally, after several weeks of waiting, I've received my CompuServe
    account.  It's nice to see that people are enjoying my raytracer
    (DKB, of course). I have noticed, however, that you are less than
    satisfied at the support I've been able to provide <grin>.
    True, I'm the first to admit that the support is poor.  I have
    little time these days to work on graphics - it takes long enough
    to answer all the questions I get asked on a daily basis from all
    across the world.

    My motivation for releasing the raytracer as Freely Distributable
    software in the first place was to allow people to have some fun
    with a program I'd developed for just that purpose.  I don't
    consider it to be a professional package - I know it's nowhere near
    that good.  I didn't make it shareware, however, because I knew I
    wouldn't have much time for support.  I didn't want the hassles of
    maintaining user lists, sending updates and notices, etc.

    There has recently been a proposal in this forum that you write
    your own raytracer to use instead of DKB.  Perhaps I can make that
    prospect a little bit easier.  Suppose we take DKB and use it as a
    base for a completely new system (the name "Renderdog" has
    been tossed around, but I'm not fond of that one <g>). I would
    like to propose the name "Software Taskforce on Animation and
    Rendering" or STAR.  I would imagine that there would be
    several packages developed such as:

     STAR Light  - the raytracer
     STAR Guider - an animation system
     STAR Maker - a user interface for StarLight

    If you decide to do this, I would like to place a few rules on the
    packages (or at least those developed from DKB):

      - they will remain freely distributable
      - support and maintenance of this new product will be undertaken
        by the STAR team (including but not limited to myself)
      - the programs will remain as portable as possible

    What do you think of this proposal?

    David Buck

#### 2.1.5.2 The Name

More on how POV-Ray came to its name.

    **************************************************************
    from Chris Young, to whom I asked if POV's name was related
    to the title of a sci-fi book I had just found on a flea market.
    **************************************************************

    Varley is one of my favorite authors and I've owned that book
    long before POV-Ray existed.  POV-Ray was originally going to be
    called Starlight or StarLite or something similar but somebody
    else, I don't know who, said we'd get in trademark trouble over
    some existing product.  Drew Wells was team leader and he picked
    Persistence of Vision based on the properties of the human visual
    system. I also felt there was a double meaning in that POV-Ray
    was the continuation (or persistance) of David K. Buck's DKB-Trace.
    I warned Drew about Varley's book but book titles aren't as messy
    as product names.  Note also that Public Broadcasting System has
    a documentary series called POV but that stands for Point Of View
    which is the filmmaking term for hand-held camera, cinema-verite
    style used in many documentaries.

    I wanted to take our team name from the Fractint Stone Soup Group
    and call us the Crystal Soup Group but I got voted down.

            Chris Young, POV-Team Coordinator

    **************************************************************
    from unknown source
    **************************************************************

    After the recent thread on the starting time I POV-Ray I did
    a search and found this post to this very news group from
    David Buck himself. The message places the birth of the POV-Ray
    project to be in May of 1991. A very historic event!

    I hope I'm not stepping on toes by re-posting
    it  :-)

    Harold

    Sun, 19 Feb 1995 19:14:44 GMT
    (STEERPIKE) says:
    >I had always presumed that Persistance of Vision was a pun on
    >the name of Salvador Dali's painting "The Persistance of
    >Memory". Is this right, and if not, how did POV-Ray come to
    > have such a poetic name? :)

    The POV-Ray project started in May 1991 when I first proposed the
    idea to a group of people on CompuServe.  They liked my DKBTrace
    raytracer but didn't like the fact that I was too slow adding new
    features to it.  They were going to re-write a raytracer from
    scratch, but I suggested that after version 2.12 of DKBTrace, they
    could take the code as is and develop it from there into a new
    raytracer.  The first name was STAR - an acronym for something or
    other.  Then someone in the group came up with "Persistance of
    Vision".  We liked it because of its reference to Dali (I
    believe the painting was actually called Persistance of Vision - am
    I mistaken?).  Moreover, it seemed to symbolize the team who
    "Persisted" to achieve their "Vision".  The
    third reference was to the phychological effect that seeing an image
    flashed on a screen causes you to retain that image in short term
    memory.  Thus, your memory was a representation of reality but not
    really reality. They all seemed to fit together to make a nice name.
    Early on, we were abbreviating the name to PVRay, but we were
    concerned about a commercial product called PV-Wave.  We agreed to
    change the abbreviation to POV-Ray and standardize on the spelling.

    >David Buck

#### 2.1.5.3 A Historic 'Version History'

The version history as it was included in PV-Ray 0.5 BETA. Notice the name changes...

    Persistence of Vision Raytracer Version History
    -------------------------------------------------

     PV-Ray was originally DKBTrace Ver. 2.12 written by David Buck. He
    donated the rights to his source code so the PV-Team could enhance
    this raytracer as a group project similar to Fractint. The source
    code for PV-Ray will always be freely distributable subject to the
    restrictions in the header files. Thanks David, for your generous
    gift!

    Version 0.02 BETA Release 7/29/91 (as STAR-Light)
    ----------------------------------
     First version is still basically DKBTrace 2.12 with a few new
     features.

     - Materials mapping added by Drew Wells.(see matmap.dat)
     - ONION & LEOPARD textures added by Scott Taylor.
     - Time to trace display added by Bill Pulver.
     - Grayscale display (+g) for IBM-PC's added by Scott Taylor.
     - Small wood texture bug fixed to create true cylinders.
     - Verbose now displays more info including file being traced.
     - Option +vO added to enable old-style terse verbose.
     - Texture.c broken into smaller modules.
     - PAINTED1, 2, & 3 added for developers.
     - BUMPY1, 2, & 3 added for developers.

    PvRay Version 0.5 BETA Release 9/07/91
    ----------------------------------
     Many more changes this time around, including...

    - Many enhancements from Alexander Enzmann
       - Bezier bicubic subpatches
       - Polynomial surfaces
       - New mapping types (sphere, etc.)
       - Sturmian sequences
       - Clipping shapes
       - (have I forgotten anything??)
    - Lots of hard work and enhancements by Aaron Collins
    - Height fields by Doug Muir
    - Bump Mapping by Doug Muir and Drew Wells
    - Interpolation by Girish T. Hagan adapted for mapping by Drew Wells
    - # and ; are now ignored.
    - case_sensitive keywords and commandline option added by Drew Wells
      > case_sensitive_yes -- All words checked for exact case.
                                 Keywords must be in upper case.
                                 (*Old DKB Style*)
      > case_sensitive_no  -- Case is ignored for all words.
      > case_sensitive_opt -- DEFAULT - All words checked for exact
                                 case except keywords. Keywords will be
                                 accepted in upper and/or lower case.
      > command line -- /ty = yes, /tn = no, /to = opt
    - cnvdat.c to convert old dat files included with pvsrc.
    - C++ style commenting - // ignore to end of line.
      and /* ignore between braces */ nesting not allowed.
    - New default style verbose trace info (+v1)
    - Old-new style verbose (+v0)
    - Verbose trace info outputs to stderr so that stats can be
      redirected to file.
    - New stats display outputs to stdout for better redirection.
    - New lighting routines by David Buck.
    - The declared colors Red, Green, and Blue in colors.dat are now
      CRed, CBlue, CGreen.
    - The declared quadric Sphere in shapes.dat is now QSphere.
    - Textures.dat has been cleaned up and commented.