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+ comp.graphics.raytracing + FAQ release V1.0 + (C) Copyright 1994 Andy Wardley + <abw@oasis.icl.co.uk> "But the Devil whoops, as he whooped of old: 'It's clever but is it art?'" Rudyard Kipling _The_Conundrum_of_the_Workshops_ This is the comp.graphics.raytracing Frequently Asked Questions (FAQ) List. It's not the most definitive ray tracing reference you'll ever come across, but then, it was never meant to be. What it does set out to do is to answer some of the questions which keep cropping up on c.g.r and to give pointers to other references. It keeps the noise down on the group and we get to spend an extra 10 minutes in bed. This is a Good Thing. It has been cobbled together by me, Andy Wardley <abw@oasis.icl.co.uk>, from answers posted to c.g.r, from information people have supplied and from other existing ray tracing lists and references, most notably, Eric Haines' Ray Tracing News and other lists. More details of these later.... You may distribute this document to whoever, or wherever you like, as long as you keep the copyright message and give correct attributions for material used. This is just to stop nasty people with a substantial lack of moral fibre from taking the document and fobbing it off as their own. The FAQ belongs to the group, I just wrote it. If you have any comments, suggestions, material, corrections, collaborations or criticisms (of the constructive kind, preferably), please feel free to send them to me (email address above) and/or to post them to the group. If you are posting to the group, it's probably a good idea to Email it to me as well, just in case I happen to miss it on c.g.r. And if you're only reading this document because your machine is locked up tracing, remember that all things come to those who wait. Andy -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- CONTENTS -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- INTRO What is Ray Tracing? 1 Ray Tracing Software 1.1 POV-Ray 1.2 Polyray 1.3 Vivid (including BOB) 1.4 Rayshade 1.5 Radiance 1.6 Others 1.7 Non-Ray Tracing Software 2 FTP Sites, Bulletin Boards, etc. 2.1 FTP Sites 2.2 Bulletin Board Systems 2.3 Mailing Lists 2.4 Others 3 Utilities and Other Software 3.1 Modelling Software 3.2 Format Conversion Utilities 3.3 Creation Creators 3.4 Texture Editors 3.5 Animation 3.6 Misc 4 Further Information and Resources 4.1 On-line Resources 4.2 Other Newsgroups 4.3 Books 4.4 Image Libraries 4.5 Texture Libraries 5 Frequently Asked Question 5.1 "Who is..." 5.2 "This picture doesn't trace." 5.3 "I traced my picture, but I can't see anything." 5.4 "Rotating this object doesn't work properly." 5.5 "Where can I find model data for..." 5.6 "How can I view these pictures?" 5.7 "Can I post binaries to this group?" 5.8 "What does this mean..." 5.9 "How can I Email someone on CompuServe?" 5.10 "What is the difference between rendering and ray-tracing?" 6 Roll The Credits... EPILOGUE -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- INTRO What is Ray Tracing? -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Ray Tracing, in a one-line description, is a method that allows you to create stunning photo-realistic images on a computer. All you need is a computer, some ray tracing software, a little imagination and some patience. The first stage of creating this masterpiece is to "describe" what it is that you want to depict in your picture. You may do this using an interactive modelling system, like a CAD package, or by creating a text file that has a programming language-like syntax to describe the elements. Either way, you will be specifying what objects are in your imaginary world, what shape they are, where they are, what colour and texture they have and where the light sources are to illuminate them. Having done all of this, you feed it into your ray tracer, sit back and wait. And wait... That's the main drawback of ray tracing - it's not fast. The software actually mathematically models the light rays as they bounce around this virtual world, reflecting, refracting and generally having a good time until they end up in the lense of your imaginary camera. This can quite literally involve thousands and millions of floating-point calculations and this takes time. Tracing images can take anything from a few minutes to many days. It's a long process, I know, but the results can make it all worth while. Ray tracing isn't the only method for creating photo-realistic pictures. There are packages like 3D Studio which uses scanline rendering, Radiance, which uses radiosity, and so on. Although these don't count as ray tracing, the methods you use from one system to the next are often sufficiently similar to warrant their discussion in this group. So if you think it's relevant, feel free to bring it up. These systems will be mentioned in a little more detail later on. -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- 1 Ray Tracing Software -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- 1.1 POV-Ray The Persistance of Vision Ray Tracer (POV-Ray) is an all-round excellent package, but there are two things that particularly make it stand out above the rest of the crowd. Firstly, it's free, and secondly, the source is distributed so you can compile it on virtually any platform. It's without doubt the most used package among the comp.graphics.raytracing crowd and well worth checking out if you haven't already. POV-Ray is based on David Buck's original ray tracer, DKB-Trace and has been (and still is) developed and supported by a whole crowd of people on CompuServe Graphics Developers' Forum (GO GRAPHDEV). For more info, see the POV-Ray docs. The latest version is 2.2 and the following list, taken from the official POV-Ray docs, details some of the main 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 (24-bit color.) * 15 and 24 bit color display on IBM-PC's using appropriate hardware * Create landscapes using smoothed height fields * Spotlights for sophisticated lighting * Phong and specular highlighting for more realistic-looking surfaces. * Several image file output formats including Targa, dump and raw * Wide range of shapes: * Basic Shape Primitives such as... Sphere, Box, Quadric, Cylinder, Cone, Triangle and Plane * Advanced Shape Primitives such as... Torus (Donut), Hyperboloid, Paraboloid, Bezier Patch, Height Fields (Mountains), Blobs, Quartics, Smooth Triangles (Phong shaded) * Shapes can easily be combined to create new complex shapes. This feature is called Constructive Solid Geometry (CSG). POV-Ray supports unions, merges, intersections and differences in CSG. * Objects are assigned materials called textures. (A texture describes the coloring and surface properties of a shape.) * Built-in color patterns: Agate, Bozo, Checker, Granite, Gradient, Leopard, Mandel, Marble, Onion, Spotted, Radial, Wood and image file mapping. * Built-in surface bump patterns: Bumps, Dents, Ripples, Waves, Wrinkles and mapping. * Users can create their own textures or use pre-defined textures such as... Mirror, Metals like Chrome, Brass, Gold and Silver, Bright Blue Sky with Clouds, Sunset with Clouds, Sapphire Agate, Jade, Shiny, Brown Agate, Apocalypse, Blood Marble, Glass, Brown Onion, Pine Wood, Cherry Wood * Combine textures using layering of semi-transparent textures or tile or material map files. * Display preview of image while computing (not available on all computers) * Halt rendering when part way through * Continue rendering a halted partial scene later There are now two official distribution sites for POV-Ray. The first is alfred.ccs.carleton.ca [134.117.1.1] and the second, more recent one, is uniwa.uwa.edu.au [130.95.128.1] The files that make up POV-Ray are: - povsrc-2.2.zip Source files for compiling POV-Ray yourself. - povdoc-2.2.zip Documentation - povscn-2.2.zip Sample scenes - povibm-2.2.exe Runtime binary for IBM PC systems. Depending on where you look, you may also find binaries for other platforms or the above archives packaged in different formats. Definately worth a mention here is Dieter Beyer's Faster Than POV-Ray (ftpovray) which is a custom build that incorporates many speed-ups and enhancements to the original POV-Ray. Not all scenes benefit from the enhancements and some may even run slower, but in certain cases, speed increases by an order of magnitude are possible. The archive ftpv20.zip is available from most of the major POV FTP sites. 1.2 Polyray Polyray is a close cousin to POV-Ray and shares many features with it. Harry Rowe <Harry.Rowe@wedowind.meaddata.com> elaborates: "If you have access to a lowly 486 or Pentium (like I use), why not try out Polyray v1.7 from Alexander Enzmann (XANDER). He is also an original member of the POV team. It does the familiar fx(u,v), fy(u,v), fz(u,v) parametric surface. I am playing with building an include file of Alan Barr's Superquadrics. It also includes: * Implicit functions f(x,y,z) // Unique to shareware/freeware tracers * Numerical expressions to include trig and dot products. * Conditional expressions * NURBS (trim curves are coming in the next release) * Glyphs (TrueType Font conversions) * Particle systems * Good animation support * For polynomial f(x,y,z), there are 3 root-solvers; Ferrari, Vieta and Sturm. Though, due to numerical inaccuracies, no amount of root-solving will help some poly surfaces from rendering correctly in all directions. You may experience some pixel drop-outs. * Focal Blur in addition to the pin hole camera. * *Finally* added the last Affine: Shearing Registered version ($35.00) uses virtual memory in addition to the coprocessor. You also don't have to spend $9.64/hr on CIS GRAPHDEV to get support from XANDER." Polyray v1.7 is currently available from wuarchive.wustl.edu in the directory /pub/msdos_uploads/graphics. See the file ply.txt for info. 1.3 Vivid (including BOB) Vivid is a shareware ray tracer for IBM PC's by Stephen Coy <scoy@microsoft.com>. Version 2, the current publicly available version, is available from several FTP sites as vivid2.zip. Registration will costs you $50 U.S. which will get you version 2.0a19, released 6/30/93. Version 3 is expected soon. Compared to POV-Ray, Vivid doesn't have as many features, but in many cases it can run faster. Source code isn't available, so the package is limited to the one platform. Stephen Coy, Christopher Watkins and Mark Finlay co-authored a book on Ray Tracing called "Photorealism and Ray Tracing in C" (see section 4.3). Distributed free with the book was an example ray tracer called BOB. This was actually a cut down version of Vivid which did include source. 1.4 Rayshade Rayshade is a free ray tracing package for unix/X11. The "official" ftp site is: - princeton.edu/pub/Graphics/rayshade.4.0 (erm...) 1.5 Radiance Radiance is a free software package that adopts a radiosity-type approach to lighting simluation. It's author, Greg Ward <greg@pink.lbl.gov>, discusses it here: "I've spent the past nine or so years developing a ray-tracing program for lighting simulation and rendering called Radiance. Although it doesn't use the typical finite-element/form-factor approach of radiosity programs, it does compute what they compute plus some. Specifically, Radiance computes diffuse, specular and directional- diffuse reflection and transmission in arbitrarily complicated environments. Here is a short description: Radiance is a suite of programs for the analysis and visualization of lighting in design. Input files specify the scene geometry, materials, luminaires, time, date and sky conditions (for daylight calculations). Calculated values include spectral radiance (ie. luminance + color), irradiance (illuminance + color) and glare indices. Simulation results may be displayed as color images, numerical values and contour plots. The primary advantage of Radiance over simpler lighting calculation and rendering tools is that there are no limitations on the geometry or the materials that may be simulated. Radiance is used by architects and engineers to predict illumination, visual quality and appearance of innovative design spaces, and by researchers to evaluate new lighting and daylighting technologies. Radiance has been written up in many technical and non-technical articles in various journals and magazines. Most recently, a Radiance-generated image appeared on the cover of the 1992 Siggraph Proceedings. This year, I hope there is going to be a long systems paper at Siggraph describing the software. The software is free, runs on most UNIX/X11 platforms (including Linux), and is available in source form via anonymous ftp from hobbes.lbl.gov (128.3.12.38) in California and nestor.epfl.ch (128.178.139.3) in Switzerland. (Please use the one that's closer.) There are hundreds of happy Radiance users world-wide, including public and private research institutions as well as engineering and architecture firms. I guess that's all I can think of to say about it at the moment... -Greg" 1.6 Others There are many other ray tracing packages available; ART, DKBtrace, RTrace, RAY4, MTV, QRT, DBW for instance, and some for distributed (parallel) tracing: XDART, Inetray, RRLib, prt, VM_pRAY. See the comp.graphics FAQ or Eric Haines' <erich@eye.com> lists for more info on these (see section 4.1) 1.7 Non-Ray Tracing Software * 3D Studio Autodesk's 3d Studio is an interactive 3d modelling, rendering and animation package for the IBM PC platform. It employs scanline rendering to achieve photo-realistic effects rather than ray-tracing. Because of this, it cannot do true shadows, reflections or refractions, but can, in many cases, simulate them accurately enough for most purposes. The package costs around $3000 or $1200 with the educational discount. -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- 2 FTP Sites, Bulletin Boards, etc. -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- 2.1 FTP Sites The following list details some of the main graphics related FTP sites, their maintainers (where known) and any other info. For a more complete list of FTP sites, see the list by Eric Haines <erich@eye.com> and Nick Fotis <nfotis@theseas.ntua.gr> from which much of the following has been taken. * wuarchive.wustl.edu [128.252.135.4]: George Kyriazis <kyriazis@esd.sgi.com> A huge repository of graphics stuff, particulary: - /graphics/graphics - get CONTENTS file. - /graphics/graphics/objects/TDDD - the TTDDD objects and converters. - /mirrors/unix-c/graphics - Rayshade, MTV, Vort, FBM, PBMPLUS, etc. - /mirrors/msdos/graphics - DKB ray tracer, FLI RayTracker demos. - /graphics/graphics/mirrors - mirrors many sites. - /pub/rad.tar.Z - SGI_RAD. - /graphics/graphics/radiosity - Radiance and Indian radiosity package. - /systems/ibmpc/msdos/graphics - loads of PC graphics stuff. * ftp.informatik.uni-oldenburg.de [134.106.1.9] : Frank Neumann <Frank.Neumann@informatik.uni-oldenburg.de> Another good site for ray tracing, particulary POV-Ray. Recently been re-organised: - /pub/pov-ray - get INDEX for full details - /pub/pov-ray/conv - format converters - /pub/pov-ray/edit - graphical editors - /pub/pov-ray/ext - source extensions - /pub/pov-ray/gen - data file generators - /pub/pov-ray/misc - other tools, ray tracers, etc. - /pub/pov-ray/new - uploads - /pub/pov-ray/obj - objects - /pub/pov-ray/pack - compression - /pub/pov-ray/pix - pictures - /pub/pov-ray/scen - scenes - /pub/pov-ray/text - text articles - /pub/pov-ray/view - viewers - /pub/pov-ray/pbin - unofficial POV binaries * alfred.ccs.carleton.ca [134.117.1.1]: David Buck <david_buck@carleton.ca> Official distribution site of dkb-trace and POV-Ray: - /pub/dkbtrace - DKB ray tracer - /pub/pov-ray - POV-Ray * uniwa.uwa.edu.au [130.95.128.1] Christopher Cason <cjcason@yarrow.wt.uwa.edu.au> Official secondary distribution site for POV-Ray. Also has utils, scenes and images, including a Hall of Fame and an Image of the Month. - /pub/povray - Official POV distribution and more. See the file CONTENTS_PLEASE_READ (or finger povray@uniwa.uwa.edu.au). * princeton.edu [128.112.128.1]: Craig Kolb <cek@princeton.edu> - /pub/Graphics - Rayshade, RT News, Wilson's RT abstracts, RT bib, Utah Raster Toolkit, Graphics Gems I, II & III code, etc. * avalon.chinalake.navy.mil [129.131.1.225]: Francisco X DeJesus <dejesus@archimedes.chinalake.navy.mil> This site was created to be a 3D object "repository" for the net. 3D objects (multiple formats), utilities, file format documents. Note that connections are refused from any sites whose name can't be resolved. If this happens, check with you network people that your namesever is running and is up to date. * hobbes.lbl.gov [128.3.12.38]: Greg Ward <gjward@lbl.gov> Official distribution site for Radiance ray trace/radiosity package. * rtfm.mit.edu [18.70.0.209]: - /pub/usenet/news.answers - the land of FAQs. Graphics and pictures directories of particular interest. [Also available from mail-server@rtfm.mit.edu. Send sending a mail message containing: help for more info] 2.2 Bulletin Board Systems The following list details some Bulletin Boards Systems dedicated to graphics and, in particular Ray Tracing. At the end of the section there is a list of BBS'es of PCGNet (Professional CAD and Graphics Network) kindly provided by Bjorn-Kare Nilssen <bjoernk@oslonett.no> * The Graphics Alternative TGA is heavily orientated around Ray Tracing, 3D Rendering, Modelling and Animation. It's the official support BBS for Vivid and has an extensive library of utilities, programs, source and images built up by its 1300+ users. Location: El Cerrito, CA, USA. Sysop: Adam Shiffman Data: (510) 524-2780 (PM14400FXSA v.32bis 14.4k, Public) (510) 524-2165 (USR DS v.32bis/HST 14.4k, Subscribers) * You Can Call Me Ray Another Ray Tracing specific BBS, this time in Chicago. Lots of interesting stuff. Location: Chicago Suburbia, USA. Sysops: Bill Minus & Aaron Collins Data: (708) 358-5611 * Pi Squared On the East Coast of the USA is Pi Squared. Alfonso Hermida is the sysop and he is the creator of POVCAD. All the latest POV files available as well as support for his own products. Location: Maryland, USA. Sysop: Alfonso Hermida (CIS: 72114,2060) Data: (301) 725-9080 (14.4K, 24hrs) * The Tackle Box Another BBS dedicated to POV-Ray with hundreds of modelling utilities, source, pictures and animations. 1.2 GIG online, with a CD-Rom Ray Tracing disk coming online shortly. Location: Edmond, Oklahoma, USA. Sysop: Neil Clark <clark@qns1.qns.com> Data: (405) 459-3301 (14.4K, N/8/1, 24hrs) * The New Graphics BBS A graphics specific system for those interested in 3D, objects, image processing, animation, MPEG, JPEG, GIF, file formats, etc. Knowledge Media "Graphics 1" CD-ROM available, 645 Mb "MultiMedia" CD online shortly. Location: ? Sysop: Bob Lindabury <bob@bobsbox.rent.com> Data: (908) 469-0049 (14.4K, 24hrs) * The Graphics Emporium BBS A BBS for the graphics professional and hobbyist to exchange ideas, information and creativity. Not dedicated to any one platform. Location: Redondo Beach, CA, USA. Sysop: ? <Emporium_Admin%Graphics_Emporium@morph.uu.holonet.net> Data: (310) 374-8805 * Boards of the Professional CAD and Graphics Network USA and Canada ------------------------------------------------------------------- SAUG BBS Bellevue WA 206-644-7115 Joes CODE BBS West Bloomfield MI 313-855-0894 CHAOS BBS Columbia MO 314-874-2930 Engineering Services Atlanta GA 404-325-0122 Autodesk Global Village Sausalito CA 415-289-2270 Route 66 Solutions Albuquerque NM 505-294-4543 The Graphics Alternative El Cerrito CA 510-524-2780 PC-AUG Phoenix AZ 602-952-0638 Convergence Spline BBS Richmond BC 604-275-3462 Graphicly Speaking Langley BC 604-534-2954 Granite BBS St. Cloud MN 612-654-8372 Tern Solution BBS Ottawa ON 613-228-0539 Canis Major Nashville TN 615-385-4268 CAD Engineering Services Hendersonville TN 615-822-2539 The Virtual Dimension Oceanside CA 619-722-0746 The Drawing Board BBS Anchorage AL 907-349-5412 The University Shrewsbury Twp NJ 908-544-8193 France ------------------------------------------------------------------- CAD Connection Montesson 33-1-39529854 Zyllius BBS! Saint Paul 33-93320505 United Kingdom ------------------------------------------------------------------- Raytech BBS Tain, UK 44-862-88340 The Missing Link Surrey, England 44-81-641-8593 CADenza BBS Leicester, UK 44-533-596725 New Zealand ------------------------------------------------------------------- The Graphics Connection Wellington 64-4-566-8450 Australia ------------------------------------------------------------------- The Baud Room Melbourne 61-3-481-6873 Sydney PCUG Compaq New South Wales 61-2-540-1842 My Computer Company Erskineville 61-2-557-1489 Slovenia ------------------------------------------------------------------- MicroArt Koper 386-66-34986 Germany ------------------------------------------------------------------- NEWS BBS Duesseldorf 49-211-680-1458 The Netherlands ------------------------------------------------------------------- BBS_Bennekom: Fractal Board Bennekom 31-8389-15331 CAD-BBS Amsterdam 31-20-6861533 Foundation One Baarn 31-2154-22143 Some of the above may require additional country or long-distance codes. 2.3 Mailing Lists Listed below is a selection of mailing lists related to graphics and/or ray tracing. If I haven't included specific details on subscription, it's because I don't know. Best bet is to send a "help" message. * POV-Ray Called the dkb-list for historical reasons (POV-Ray was based on David Buck's "DKBTrace"), the list exists for users of POV-Ray and associated products, on all platforms. Subscription: listserv@trearn.bitnet Body Text: subscribe dkb-l <Your full name> Posting: dkb-l@trearn.bitnet * Rayshade Mailing list for Rayshade users, mainly on UNIX platforms. Subscription: rayshade-request@cs.princeton.edu Posting: rayshade-users@cs.princeton.edu * Radiance Greg Ward, the author of Radiance has a distribution list of all users. Register with him: greg@pink.lbl.gov * Imagine For users of the Imagine 3d rendering and animation package for the Amiga and, more recently, the IBM PC. Subscription: imagine-request@email.sp.paramax.com Posting: imagine@email.sp.paramax.com * Toaster This mailing list deals with the Video Toaster system for the Amiga. Subscription: toaster-request@bobsbox.rent.com Body Text: subscribe <address> toaster Posting: toaster@bobsbox.rent.com * Lightwave Lightwave is part of the suite of programs that come with the Video Toaster system for the Amiga. Subscription: lightwave-request@bobsbox.rent.com Body Text: subscribe <address> lightwave Posting: lightwave@bobsbox.rent.com * 3D Studio Autodesk's 3d modelling and scanline rendering system for the IBM PC. Subscription: 3dstudio-request@bobsbox.rent.com Body Text: subscribe <address> 3dstudio Posting: 3dstudio@bobsbox.rent.com 2.4 Others * CompuServe The CompuServe Graphics Developers' Forum (GO GRAPHDEV) is the home of POV-Ray (section 8 POV Sources and section 9 POV Images) as well as other development projects including fractals, animation and morphing. You can get information of joining CompuServe (in the US) by calling (800) 848-8990. CompuServe access is now available in other countries, including Japan and Europe. * America On-Line AOL also has a section (PCGRAPHICS) dedicated to POV-Ray support. * World Wide Web Ian Grimstead <I.J.Grimstead@cm.cf.ac.uk> has 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 and to other ray tracing web pages. - hhtp://www.cm.cf.ac.uk/Ray.Tracing/ Marius Watz <mariusw@ifi.uio.no> has set up a WWW page for POV utilities, containing information about some of the most popular ones and allowing you to download them directly from the page. - hhtp://www.ifi.uio.no/~mariusw/pov/utilities.html -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- 3 Utilities and Other Software -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- 3.1 Modelling Software * MORAY MORAY, by Lutz and Kretzschmar [CIS: 100023, 2006], is a shareware modeller for PC's that directly supports POV-Ray 2.x primitives and more. Registration is US $59 which will get you a protected mode version, allowing full memory usage, plus all the usual support and upgrade info. The following, taken from the manual of the latest version, 1.5, describes MORAY: 1. What is MORAY? MORAY is a program with which you can design scenes for the POV- Ray raytracer to render. Contrary to normal scene design, with MORAY you design the scenes graphically. Up to now it was pretty difficult to imagine what the scene looked like, without laying it out on graph paper, or doing many test renders. MORAY is like a graph paper, it lets you place and change objects in wireframe while you see them. MORAY then generates the text file that POV needs to read. MORAY can thus also be used as a rapid prototype tool, to place objects quickly and write the scene file. You can then edit the scene file to suit your needs, just like you have been doing up to now. MORAY stores and works with POV-Ray primitives, as opposed to normal CAD systems, which mostly convert all objects to triangle meshes or similar polygon based formats when outputting. This ensures optimum performance and image quality from the raytracer. If you're a POV enthusiast and have access to CompuServe you should check out the GRAPHDEV forum for the latest news and tips on using POV. The RayTracing conference on PCGnet also carries lots of tips for POV. If you want to obtain the latest version of POV-Ray you can probably do so at the same source you obtained MORAY from. 2. MORAY Features The emphasis in designing MORAY was to be able to work as intuitively and as graphically as possible. Most of the work can be done with the mouse. Three 2D views and a 3D view of your scene are visible on screen. You can perform all transformations of the objects in the 2D views with the mouse. The 3D view shows what the current camera will see, i.e. how POV will raytrace it. MORAY allows you to, - scale, rotate and translate an object interactively on the screen. - define cameras with which to view your scene, that will show the scene in wire frame as POV-Ray will raytrace it. - graphically place a bounding box around an object. - automatically create bounding boxes of any objects, including nested objects. - make CSG or composite objects that can be nested arbitrarily deep. - assign textures from the TEXTURES.INC file to your objects. - define a new texture from within MORAY. You can then hand-tune this texture and MORAY won't interfere. - place imagemaps graphically on objects, eliminating the tedious trial and error approach. - manipulate the control points of a bezier patch to create shapes not easily created otherwise. - create bezier patch meshes that consist of more than just one bezier patch primitive. - create rotational, translational and tapering sweeps that are then output as smooth triangles. - copy complex nested objects. - create multiple copies of an object transforming each copy by amounts you specify in one easy step. - specify the complexity of on screen objects. - specify a region of the 3D view to render. - integrate POV-Ray with MORAY, so that you can seemingly call POV-Ray from within MORAY. 3. Requirements MORAY requires at least a 386, a VGA card and a mouse, although I cannot recommend this set-up. The minimum system, if you want to do some larger scenes, would be a 486DX/25 and 4MB memory, the shareware version needs 2MB EMS. EMS Memory is not required in the registered version, since it is a protected mode version. No specific software is required. You need to have POV-Ray 2.0 to raytrace the scene. * POVCAD (erm...) * PV3D (hmm...) * Blob Sculptor Blob Sculptor, v1.0, by Alfonso Hermida, Steve Anger and Truman Brown allows you to model shapes using blob primitives. Output is to RAW, DXF, BLB (internal format), POV, Polyray, Rayshade and CTDS. In addition, the Windows version, ported by Ronal Praver, supports NFF, VideoScape and others. NeXTStep and Open GL ports are expected soon. 3.2 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 file format to another: * 3DSPOV18.ZIP - Reads 3d studio mesh files. Writes out to Raw, Povray (1 & 2), Vivid and Polyray. (1993, Anger & Bowermaster) * DXF2POV.ZIP - DXF to Povray 1 conversion program. (1992, Collins, Wells, Farmer & Gibeson) * DXF2RAW2.ZIP - DXF to Raw conversion program. (1992, Coy, Barber, Daigle & Shiffman) * DXF2V22.ZIP - DXF to Vivid conversion program. (1992, Coy, Barber, Daigle & Shiffman) * DXF3DS.ZIP - DXF to 3DS conversion program. (11, Yost/Autodesk) * OBJ2ASC2.ZIP - Wavefront object to 3d studio ascii converter. (1993, Knight) * RAW2PV18.ZIP - Excellent utility that allows the user to adjust the level of smoothing to apply to raw data as it is translated to Povray (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. (1993, Anger) * RAYL210.ZIP - Helpful utility to convert uLathe (an object creator program for windows) files to RAW, Povray 1 & 2.x or Vivid 2 format. (1993, Koehler) * TDDD2ASC.ZIP - TDDD (Imagine) to 3D studio ascii file converter. (1993, Knight) * TGA2GIF.ZIP - Converts targa files to gif files. (1991, Coy) * TGA2POV2.ZIP - Converts targa files to Povray 1.0 objects. (1992, Steeves) 3.3 Creation Creators Utilities to aid in the creation of ray tacing objects: * BOXER1.ZIP - Object generator for Povray 1 (makes things like bathroom tiles and such based upon user input). (1993, Miller) * BRANCH1.ZIP - Tree creator for Povray 1. (1992, Weller) * CHAIN11.ZIP - Generates interlocking chain links for Povray 1.0. (1992, Koehler) * CM100.ZIP - CircleMaster utility for working with quadric spheres and ellipsoids; writes output to Povray 1.0. (1992, Brown) * COIL2.ZIP - Creates coiled objects for Povray 1.0. (1992, Kirby) * COIL2V.ZIP - Creates coiled objects for Vivid 2. (1992, Kirby & Cox) * CTDS230.ZIP - Connects a series of xyz dot coordinates. Though this may not sound like much, this is an extremely helpful utility. Supports Povray, Vivid and Polyray. (1993, Brown) * FORM.ZIP - 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 Povray 1, 2 or .plg. Interesting program, complementary to LPARSER. (1993, Rowbottom) * FRGEN14.ZIP - Fractal Landscape (and other shapes too) Generator. Though the program supports Vivid and Povray 1 & 2 directly, by selecting raw output you can smooth triangles out with RAW2POV to create nice hills and dales. (1993, Anger) * GEODOME1.ZIP - 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. This gets my vote, but then it would... (1994, Wardley) * LPARSER2.ZIP - L-system creator and mutator. This program is particularly strong in the creation of organic looking forms. Many data files are included with the program, which can be edited or mutated to interesting effect. The language of l-systems is not intuitive but the results can be truly stunning. The l-system file that is read into the program can be outputted to DXF (both R12 and 3D faces), Povray 2.x, RAW and Renderstar VOL. A couple of accessory files are included with the main program and are strong programs in their own right. LVIEWER, is a wire-frame viewer that reads .3DS, .RAW, Fractint .RAY, ARE-24 .POL and Lparser/ Renderstar .VOL files. Rotation, zoom and pan the "camera" position, which can be saved to a file. This file can then be read into LV2POV. (1993, Lapre) * LV20POVID - Newer and more powerful than LV2POV, this program reads an lviewer info file and generates data files in Povray (1 & 2.x) and Vivid formats. The program's main strength lies in landscape generation. (1993, van der Mark) * PLANT05.ZIP - Fractal plant generator. Outputs supported are Povray (1 & 2), Polyray and CTDS (Connect the dots smoother). (1993, Bryerton) * SUDS2.ZIP - Random positioning of lots of spheres (or other objects) based on a variety of selections. (1994, Farmer, Wegner & Schwan) * TWISTER1.ZIP - Utility that will create spirals, coils, etc., of blobs, cubes or sphere. IBM PC executable with source, output to POV 2.x format. Another fine utility, but then I would say that... (1994, Wardley) 3.4 Texture Editors * CMAP11.ZIP - Interactive color map creator for Povray. (1993, Lutz & Kretzschmar) * TCE20.ZIP - The color editor for Povray 1. (1991, Farmer) * TCEV20.ZIP - The color editor for Vivid. (1991, Farmer) * TEXMAKE2.ZIP - Early version of a utility to assist in texture creation in Povray 2.x. (1993, Sigler) 3.5 Animation * AWKANI.ZIP - AWK script to output Povray animation data. (1992, Farmer) * DTA208.ZIP - Dave's Targa Animator (latest version 2.08) animates .tga frames into .fli's and .flc's. (199?, Mason) * PVQUAN16.ZIP - PVQUAN 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.ZIP - Set of animation utilities, not raytracer specific. (1991, Jarik & Hassi) * RTAG21.ZIP - Ray Tracing Animation Generator (not raytracer specific). A powerful program with its own language which supports, amongst other things, spline path generation. (1993, Sherrod, $20 shareware) * SP03.ZIP - Spline paths for animations. Many output formats (Povray, Vivid, Polyray, 3DV, Wire 3D) and acceleration and deceleration are supported as well. (1992, Mason) * ZOOM11.ZIP - Interpolates steps between two positions for Povray 1.0. (1993, Brown) 3.6 Misc * DISP - an excellent viewing and post-processing utility for DOS. Available as disp181a.zip on simtel mirrors. * FRACTINT - The ultimate fractals generator for the PC. Invaluable for creating height fields, colour maps, viewing gifs or just creating fractals. Latest version 18.2 available as frain182.zip from wuarchive. (1990-93, The Stone Soup Group) * NEOPAINT - A useful shareware paint package (registration US $45) for creating images, height fields, etc., or just touching up finished artwork. Available from wuarchive. * NETPBM - A collection of utilities for UNIX (source distribution) and some other platforms that convert practically any format to any other, amongst other things. Available from wuarchive in /graphics/graphics/packages/NetPBM. (1991-1994 Poskanzer et al.) * PICLAB - An excellent package for converting and post-processing images. The version I have is 1.82 (1990 Crocker), but I'm sure there must be a more recent one. -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- 4 Further Information and Resources -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- 4.1 On-line Resources * Ray Tracing News Eric Haines <erich@eye.com> has put together a phenomenal amount of information on ray tracing. This he collaborates 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 ftp sites, including: - princeton.edu pub/Graphics/RTNews Also at Princeton in the /pub/Graphics/Papers directory, you can find Eric's ray tracing and radiosity bibliographies: "RayBib.*" and "RadBib.*". Eric has also put together an FTP list which he is currently in the process of updating. * 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": - wuarchive.wustl.edu graphics/graphics/bib/RT.BIB.Speer/ - karazm.math.uh.edu pub/Graphics/ - 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 and to other ray tracing web pages. - hhtp://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 most the sites listed above. * Paper Bank Project Juhana Kouhia <jk87377@cs.tut.fi> has collected together various technical papers in electronic form. Contact him for more information. 4.2 Other Newsgroups Some other newsgroups that may be of interest to you are listed below. Most of these have FAQs of their own which are available from rtfm.mit.edu [18.70.0.209] in the directory pub/usenet/news.answers - comp.graphics - comp.graphics.algorithms - comp.graphics.research - comp.graphics.visualization - alt.graphics.pixutils - alt.3d 4.3 Books Title: Ray Tracing Creations Authors: Drew Wells and Chris Young Publisher: The Waite Group Year: 1993 ISBN: 1-878739-27-1 US Price: $39.95 (including disk) 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: Adventures in Ray Tracing Author: Alfonso Hermida Publisher: Que Corp. Year: 1993 ISBN: 1-56529-555-2 US Price: $27.95 (including disk) This book looks at Alexander Enzmann's ray tracer, Polyray (see section 1.2), and the author's own modelling system, POVCAD (see section 3.1) which runs under Microsoft Windows. The two work well together and the software is fairly well up to date. 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: - wuarchive.wustl.edu graphics/graphics/books/erratas/Adventures-In-* Title: Photorealism and Ray Tracing in C Authors: Christopher Watkins, Stephen Coy, Mark Finlay Publisher: M&T Books Year: 1993 ISBN: ???? US Price: ???? (including disks) 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. Title: Making Movies on Your PC Authors: David K. Mason and Alexander Enzmann Publisher: The Waite Group Year: 1993 ISBN: 1-878739-41-7 US Price: $34.95 (including disks) 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: 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: - wuarchive.wustl.edu /graphic/graphics/ray - ftp.funet.fi /pub/graphics/packages/ray-tracing/oort 4.4 Image Libraries A CD is available containing raytraced images, programs and utilities. Title: L'ATELIER D'ATON (2nd Edition - October 1993) Publisher: D.P. Tool Club 59657 Villeneuve d'Ascq B.P. 745 France Contact: Nicolas Kelemen - CompuServe 100012,1410 Chris Morris <cwm@hopper.itc.virginia.edu> is in the process of putting together another CD of images. Contact him for more details. 4.5 Texture Libraries There is a library of building related textures (bricks, stone, etc.), for use as image maps at: - wuarchive.wustl.edu /packages/architec/Textures -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- 5 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. At the moment, the list is fairly short, but then the group hasn't been going that long. As more questions get added, I'll no doubt re-organise and categorise the questions better, but for now you'll have to take them as you find them. 5.1 "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 [Compuserve ID: 71477,221] 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: - uniwa.uwa.edu.au /pub/povray/HALL_OF_FAME * Andrew Denton Andrew H Denton, or AHD, <guardian@netcom.com> is a professional juggler and ray tracing artist. He uses Lightwave on 2 040 Amigas and "lots of other toys". Dragons feature heavily in his artwork and some of the pictures are truly stunning. Images (no models) at: - icecube.acf-lab.alaska.edu /pub/dragons/graphics/new/ahd * Dan Farmer One of the original POV-Ray development team, Dan [Compuserve: 70703, 1632] or <Dan.Farmer@f524.n125.z1.FIDONET.ORG> 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!" You can get frosty.gif from: - uniwa.uwa.edu.au /pub/povray/HALL_OF_FAME Unfortunately, Dan doesn't release his source code any more due to certain unscrupulous sorts using his images for commercial purposes without payment or even permission. Him keeping the source is his proof of ownership. The Mira dataset for the face is now also available at uniwa. Dan is often around on the group and is very unselfish in spending time answering questions. He has a quirky mailbox which goes AWOL if you send him mail using elm. * 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 [Compuserve: 70353,100] 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: - uniwa.uwa.edu.au /pub/povray/HALL_OF_FAME /pub/povray/images /pub/povray/scenes Particular ones to look out for are MEAT (eyeballs mincing in a meat grinder), BENZ9 (model of a 1928 Mercedes Benz), DIVER1 & DIVER4 (pictures of deep sea divers with masks, SCUBA, etc), CAMERA, BUGS, SLUGS, FISH, etc., etc., the list goes on. * Andy Wardley Hmmm. Modesty would normally prevent me from including myself in this section, but I've had so many requests and questions about "geodome" that I'll use this chance to answer some of them. Most questions have been about me releasing (or not, as the case may be) the scene files. In particular, the sky texture has been in heavy demand. At the moment, however, I'm working on several other pictures that use this texture and variations on it. When these are complete and I'm happy that I've had a good run of "exclusive use" of the sky, I'll probably open it up to the rest of the World. I *can* tell you that there's no trickery involved:- it's just a normal, layered POV texture. The geodome was created using a utility I wrote specially for the occasion. It's available as geodome1.zip from uniwa, with source included. I'm curently working on Another utility, tentatively called Poly<something> which will do geodomes and MORE! It will actually create, manipulate and tessellate all manner of polyhedra. Expect it around the middle to end of June '94. The plasma is a turbulent marble texture, the green cloud is a bozo. Use of the filter keyword provided the transparency. Finally, the floor is a height field. I just took a <mumble> and then <mumble> <mumble> to create a blocky effect. 5.2 "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 section 1.1 for where to find them. Mike Miller's meat.zip seems to be one which crops up regularly. Like most of Mike's work, meat.zip is POV-Ray version 1 syntax and requires the aforementioned tweaking. Without it, you'll get a big white rectangle across the picture. Mike also defines a "Silver" texture in fork.inc which conflicts with one in colors.inc. You'll have to change both references to it in fork.inc to something else, like "MMSilver", for example. * 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. E.g. -L/users/abw/povray/include The POV-Ray docs can help you out here. What do you mean "I haven't got the docs"? Go get them. See section 1.1 for where to find them. If you haven't actually got the include files, the same applies. 5.3 "I traced my picture, but I can't see anything." 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 } 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. 5.4 "Rotating 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. 5.5 "Where can I find model data for..." avalon.chinalake.navy.mil is probably the best site you'll find for 3D model data. See section 2.1 for more details. 5.6 "How can I view these pictures?" If you're using UNIX, the netpbm package is what you need. It converts practically any format to any other and does a whole host of other things. To view the images, you can use XV which is available as a source distribution from many sites. If you're on a PC, it's a pretty good chance that you want to convert a .tga into a .gif, isn't it? (You did use the +ft switch on POV-Ray to get a .tga didn't you?). For this you can use PICLAB or tga2gif.zip. Details of where to find these packages can be found in section 3. 5.7 "Can I post binaries 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.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, but what you should do is post it to alt.binaries.pictures.misc. You'll have to uuencode it and split it into small (<64k) parts. Remember to put an informative title on it 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 this text message to comp.graphics.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 alt.binaries.pictures.d (the discussion group). If it's a utility you're posting, it should go to alt.binaries.misc instead of 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 comp.graphics.raytracing to announce it in the same way. 5.8 "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 by adding them together (union), taking one away from the other (difference) or getting the part where they intersect (intersection). * Height Field - An image that has extruded to be 3 dimensional. Typically, the lighter areas will be high, and the darker areas lower. 5.9 "How can I Email someone on CompuServe?" Before you do, remember that they have to pay for every message you send. DO NOT send binaries or large files without checking first that it's OK. To mail to a CompuServe ID from the Internet, replace the comma with a period and stick "@compuserve.com" on the end. For example: 78654,321 become 78654.321@compuserve.com 5.10 "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. -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- 6 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> 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> 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 [CompuServe: 70703,1632] 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 <cjcason@yarrow.wt.uwa.edu.au> who gets the coveted "Also- Does-His-POV-Bit-Especially-Being-Admin-of-the-POV-Site#2-And-Answering- Questions-As-Well". Sorry if I've forgotten anyone. Thanks anyway. -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- 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. -------- TO DO: POVCAD review PV3D review