SGI Dogfight

Last updated
Dogfight
SGI Dogfight Cockpit.png
The view from inside of a cockpit
Developer(s) Gary Tarolli
Publisher(s) Silicon Graphics Incorporated
Platform(s) SGI Workstations
Release 1985 as a free demo
Genre(s) Flight Simulator
Mode(s) Single Player, Multiplayer

Dogfight is a demonstration program initially written by Gary Tarolli (later founder of 3dfx) at Silicon Graphics, Inc in the summer of 1983. [1] [2] It represents landmarks in two key areas of Internet development: games and multicasting, and notable advancement in creating rendered virtual environments.[ citation needed ]

Contents

Overview

Dogfight might more properly be referred to as three programs, flight, dog, and shadow. Flight is a flight simulator, dog is an air combat game in which multiple people use the flight interface to control their aircraft, and Shadow is an observation program that allows a user to see what a user of either dog or flight sees. [3] [4]

dog and shadow could also be run in "airshow mode", using the -i and -o command-line switches. With -o, the path taken by the plane would be saved to a file instead of being broadcast to the network. With -i, the user could specify a file containing a saved flight path of this sort, and it would be displayed. Missiles fired by a plane in this mode would not affect planes in non-airshow mode. The intention was for the user to be able to record the paths of several aircraft, and then, by replaying them simultaneously, to be able to display complex aerial formations with multiple planes. [3]

At some point, the -h command-line switch was also added. This would replace the standard instrument panel with a head-up display (HUD). Such a display was commonly used in military aircraft and would allow for a larger view, but at the cost of a slower update rate. [3] [4] This was added because Williams Air Force Base was interested in using flight for F-16 training, debriefing and "human-interaction studies", but wanted it to have a HUD similar to the HUD on a real F-16. [5]

The following planes were available:[ citation needed ]

Later versions added:[ citation needed ]

History

Flight was written in the summer of 1983 by Gary Tarolli, as a demo for SGI workstations. [1] [2] It was inspired by the Blue Angels airshows at Moffett Field, across the street from SGI's original headquarters. [1] [6]

In 1984, networking capabilities began to be added. Initially, two workstations were connected by a serial cable. This allowed about 7 frames per second and 500 polygons per second on a machine with a Motorola 68000 CPU capable of approximately 1 MIPS. By SIGGRAPH 1984, XNS multicast support was added, allowing play over an Ethernet network. [1] [2] After the event, the networked version of Flight was distributed on all SGI workstations. [2] In this networked version, users could see each others' planes, but could not interact with them. [1]

Probably in early 1985, dog was created, [1] [2] and dog and flight were shipped as demonstration software included with SGI workstations. Message packets were transmitted at frame rate, and the number of players was capped due to bandwidth limitations, although sources differ as to whether this cap was 10 players [6] or a value in the tens of players. [1] Due to the network congestion resulting from so many packets being transmitted at frame rate, many system administrators removed dogfight from newly installed systems in order to prevent abuse of resources. [1] Other sysadmins limited play to restricted off-peak hours.[ citation needed ]

Dead reckoning was later added, to reduce the amount of data that needed to be transmitted. [6]

In 1986, UDP broadcast protocol capability was added (using port 5130). [7] [8] [9] Information was transmitted via broadcast packets and at frame rate, meaning that the program made intensive use of network resources and even a small number of players was capable of saturating an Ethernet. So while it was probably the first game to use the Internet Protocol Suite, gateways would refuse to transmit UDP broadcast packets, and thus could not be played across the Internet itself. [8]

By 1988, with the introduction of SGI's 4D series of machines, Dogfight had forked, with one version running on most SGI machines of the time (3000 series, 4DxxG's, Personal IRIS, GT, GTX) and another for use only on the higher-end GT, GTX and VGX machines. [3] These could interoperate, with both versions playing in the same game. The 4D/20 was observed to run dog at around 12 frames per second, while the faster 4D/70 would be capable of 20-25 fps. The other version was observed to run on a GT at around 15 frames/second. [10] In the Irix 6.5 documentation, it was noted that the Boeing 727 and F-14 were not available to choose as planes in the normal version of the software, but were present in the GT/GTX/VGX version. [3]

SGI would supply the source code to IRIS owners upon request if a non-disclosure agreement was signed. [10] [11] Some Usenet posts claimed that the code was not supplied standalone, but as part of a "Software Exchange Release Tape". A fee of $100 was charged for this, and the user had to specifically request that the dog source code be included on the tape. [12] Others stated that this was for the physical media and shipping/handling, not the source code itself, [13] and that no charge was made if the IRIS owner supplied SGI with a blank tape of their own to put the code on. [14] Based on the dates of the various postings, it is possible that SGI initially supplied the code for free, but began charging for it at a later date.

Several programmers used this code as an example, to teach themselves UDP and how to use it in their own code. [1] [2]

For the IRIX 3.3 version, circa 1989, IP multicast capability was added, [3] and the game became playable between any compatible hosts on the Internet, assuming that they had multicast access (which was quite uncommon). The multicast address was 224.0.1.2 (SGI-DOG.MCAST.NET), [15] making this only the third multicast application to receive an address assignment, with only the Versatile Message Transaction Protocol (VMTP) protocol (224.0.1.0) and the Network Time Protocol (224.0.1.1) having arrived first.[ citation needed ] SGI would later use the same address for their objectserver daemon, which handled GUI icons. [15] [16] [17] [18] This caused confusion for some system administrators.

Unofficial forked versions

Due to the availability of the source code, various SGI customers created and distributed their own unofficial modifications to the original flight program.

The point-to-point communication fork

A version replacing the UDP broadcast with point-to-point communication between two hosts was created at the Lund Institute of Technology in Sweden. The source code patch for this was posted on comp.sys.sgi in September 1989. The reason given for this fork was to allow machines on different subnets to play against each other. [19] It may also have been intended to reduce network congestion compared to the broadcast version, and probably pre-dated the addition of multicast to the official version.

The air traffic control server, and a different TCP/IP implementation

Prior to 1988, the US Army's Ballistic Research Laboratory (BRL) had a copy of the XNS version of the software, but XNS did not work on their network. An engineer by the name of Ron Natalie had access to the source code and was able to create a TCP/IP version. [20] [21] [22] This version communicated with a central server with its own "air traffic control" display.

There is no record of code from this version being used in the "official" version, or of its own networking implementation influencing the official one in any way. This means that the BRL version is probably an independent fork with different TCP/IP networking, which may not have been compatible with SGI's own. It may not even have used port 5130.

A server program called atc (Air Traffic Control) for dog was mentioned on comp.sys.sgi in November 1988. [23] [24] This was probably Ron Natalie's air traffic control server, running on the BRL's forked version of dog. There is no evidence of such a feature ever being added to the "official" version.

Porting for Sun Microsystems compatibility

In a 1992 thread on the rec.aviation.simulators Usenet group, [25] a list of available flight simulators included a port of dog/flight to pixrect - a "low-level raster operations library for writing device-independent applications for Sun products." [26]

This port was described as "(an) unauthorized copy of SGI flight/dog programs ported to run with pixrect. Very difficult to find one of these, and probably not legal. Nice fast network dogfighting. Tends to bog down the whole LAN with packets."

Another Sun port - specifically compiled for Sun's SPARCstation hardware - was also mentioned.

In a 1990 post to comp.sys.sgi, [27] a Sun port was mentioned which "runs reasonably well on a colour GX Sparcstation although it doesn't fill the polygons so a lot of the realism is lost". It is not clear whether this was a third Sun port, or whether it was one of the ports listed in the rec.aviation.simulators thread.

The author of the thread stated that he had received this version in source code form, as a combination of the original SGI source code and a library to emulate SGI's graphics. In a later post, [27] he stated that he had been informed by SGI that the source code should not have been made publicly available, and was distributed in violation of an NDA. He also mentioned that he had originally downloaded it from an FTP server.

Sci-fi craft, World War 1 planes, and the X-29

In a 1993 Usenet posting, one user mentioned having seen a version of flight with X-wing and TIE fighter models in the autumn 1987 issue of SGI's house magazine "IRIS Universe". [28] In a reply, a user from NASA's Langley Research Center said that they had had such a version running on an SGI 3130, and that as well as new vehicles there were also new weapons for some craft. The full list was as follows:

However, they only had a compiled binary of this version, and not the source code.

In a 1994 Usenet post, another user claimed authorship of the modified version, and offered to supply source code "for a price". The same user also stated that "It might need some changes for some of the newer machines." [29] Whether this user was indeed the author is not confirmed.

In an earlier Usenet posting, another user had claimed that the Klingon craft could cause lasting terrain damage with its weapons, leaving "craters in the Earth". [30]

Asked about this version, flight lead developer Rob Mace said that it had come "from a university", and that due to the copyrighted status of Snoopy and the sci-fi vehicles, SGI could not legally supply copies of it. [31]

The Klingon vessel may have had unlimited maximum speed, and may also have been immune to stalling.[ citation needed ]

Developers

A missile being launched SGI Dogfight Missile.png
A missile being launched

The manual page for the IRIX 6.5 (circa 1998) version of the program lists the following: [3]

Gameplay

The "city of lights"

In a 1991 Usenet posting, one user asked about an "interesting city" which the manual had claimed would exist north-north-west of the airport. Tarolli and others explained that there was no physical city at that location, but that lights were shown at night as if there were a city there. [34] [35] [36]

SAM threat cones

Pressing 'T' (shift+'t') in-game would cause wireframe domes to appear around the small brown rectangles in the swamp. These rectangles were intended to represent surface-to-air missile (SAM) sites, and the domes would represent the regions in which the player was in danger from the missiles. This was added at the request of Williams Air Force Base, as part of the changes that included the -h option described earlier. [5] This behaviour was not documented. [33]

The game did not in fact include code to fire SAMs from those sites, merely to show the "threat cones" that would exist for SAMs in these locations. However, a forked version was created (presumably by Williams AFB personnel) that did include this feature. [33] The University of Calgary in Canada possessed a copy of this version. [37] In a Usenet post referring to this version, David Jevans of the University of Calgary mentioned that several other versions of flight now existed, including a version running on the IRIS Power Series with Gouraud shaded planes. [37]

SAMs were added to the official version in a later revision. However, they were only added to the "low end" version, not the GT/GTX/VGX version. [38] [39] In this revision, the SAMs could not be intercepted, had higher acceleration than the player's sidewinders, and would detonate themselves after 10 seconds when they ran out of fuel. If the user had a weapon in flight (e.g. a rocket or sidewinder) it would be automatically destroyed at the moment the SAM was launched. The user would then be unable to fire any more weapons until the SAM was destroyed.

A user in Germany had access to one of these versions, although it is not clear which one. [40]

In-game physics

Yaw and roll coupling

The game's physics did not include yaw/roll coupling. Tarolli knew that this existed, but did not have a reference for the relevant equations and was unable to derive them himself. He was also unsure how much of an effect the shape of the wings would have, and whether yaw and roll would be strongly coupled for all shapes of wing. [41] [42] As a result, he was unable to implement it in code.

Stall and spin

Two users complained about the game's stall/spin physics, arguing that stalls and spins did not occur as often as they would in real life, or in as many circumstances. They also complained about unrealistic behaviour when a stall did happen. [43] [44]

In his response to this, Tarolli pointed out that while minor stalls were predictable, violent stalls were not. He also noted that modelling minor stalls would depend heavily on the wing design, and that it would require custom equations to be coded for every different wing shape on each of the planes. The calculations involved in modelling minor stalls would also be intensive and complicated enough to cause significant in-game slowdown. [45]

At least one user felt that the criticism levelled at Gary for the in-game physics was unfair, noting that flight and dog were intended primarily as fun games, not as precise simulations. He added that the relevant aerodynamics were often described in "a highly qualitative fashion" in relevant books, and that coding them into a simulation could be extremely difficult even if one had been able to learn them from such a book. [46] Tarolli himself noted that since he had not been able to model a real stall, he had coded random spins for very bad stalls (depending on how bad the stall was), in the hope that this would be "something fun" for the players. [33] He also stated that "half the things in flight are meant to be real - the other half are there to make dog more fun than it would be if things were too real."

Use in academic research

1989

A group of researchers interfaced the flight simulator with the US military's SIMNET. [47] In their report, they stated:

"We were able to translate the SG "Dogfight" PDU's by "stealing" packets from the ETHERNET via a PC/AT with an Excelan 205E ETHERNET board installed. The software written to perform this operation uses UDP/IP to capture the SG broadcast packets and saves them to a disk file. Information contained in the SG PDU was reformatted or translated into SIMNET type packets, and then retransmitted over the ETHERNET to the SIMNET M1 tank modules."

The simulator itself ran on a Silicon Graphics 4D/70GT workstation.

1990

A researcher at the US Air Force Institute of Technology attempted to reduce the cost of flight simulators used in pilot training by using a head-mounted display with a simulator that could run on PC hardware. [48] As part of this, an attempt was made to port dog/flight to a PC platform based on a 20MHz 80386 processor with 80387 coprocessor, and a Real World Graphics Ltd. PC Reality board containing two Intel i860 RISC processors. The PC was running ESIX, a version of System V UNIX. Due to the presence of the head-mounted display, the PC also had to host a device to track user head movements.

The flight simulator program needed to maintain cross-platform portability, so rewriting it in assembler instead of C was not allowed. Calls to the SGI hardware graphics pipeline were "emulated", translated on-the-go to calls to the PC Reality board's library functions.

The planes used in the experiments were the F-14D, F-16, and Cessna C150. The Cessna model had a lower polygon count than either of the other two planes. Problems were mentioned with the PC's graphics software being unable to handle the F-15 model, although this may only have applied if another plane was also present.

For this experiment to be considered a success, the PC would have to achieve a frame rate of at least 15fps with Z-buffered, flat-shaded polygons. The PC's performance was also compared to that of the Silicon Graphics IRIS 4D/85GT with an unmodified version of the flight simulator.

It was noted that the unmodified version of dog used "makes extensive use of the Silicon Graphic's immediate mode graphics pipeline. In addition to including the new graphics functions released with the SGI 4D architecture, the program contains significant use of older functions that constituted the outdated SGI IRIS 31XX graphics pipeline methods. The SGI 4D machines provide built-in support for those older methods; however, they clearly identify that those methods do not optimally exploit the graphics pipeline provided in the 4D architecture."

However, the experiment was not a success. Some of the SGI functionality could not easily be ported/emulated, and was either omitted or replaced with a workaround. Wing stalls and G-limits were not enforced and all the aircraft were able to pull outside loops. Collision detection also had to be omitted, allowing the plane to fly through hangars, hills, and mountains. Furthermore, the PC Reality board was not able to support the polygon count or frame rate claimed, and some advertised capability was missing. Its approach to 3D graphics did not "allow for methods that write directly to the screen in device coordinates.", which caused problems. Only 4 frames per second were obtained, and even in tests with "an out-the-window view without the runway, buildings, or other terrain visible" no more than 10 fps could be achieved.

An additional research goal had been to network the PC and IRIS together, and to have them run dog interoperably. This was not achieved in the time available. One problem was that ESIX's UDP/IP support did not support programming below the OSI transport layer, unlike SGI's.

1991

Code from the SGI flight simulator was incorporated into a project to develop a low-cost flight simulator using object-oriented programming techniques and the C++ language. [49]

1992

Another group of researchers modified flight to log the actions of the human "pilot", and to use these logged actions as input to an "induction program". This program would use machine learning to create an autopilot for a specific flight plan. [50] The researchers chose the Cessna as their plane, stating that it was easier to learn how to fly the Cessna than any of the others. They also claimed that the rudder did not have "a realistic effect on the aircraft", although it is not clear if this claim applied only to the Cessna or to any/all of the other planes available. A poster on comp.sys.sgi had previously noted that the rudder would have a significant effect on a real-life Cessna, but had very little effect on the simulated Cessna of the flight program, and almost no effect on the other simulated planes in flight. [43]

The researchers noted that the flight simulator was non-deterministic, since it "runs on a multi-tasking Unix system, not on a dedicated real-time system. Thus, it is not possible to give a guaranteed real-time response because the flight simulator can be interrupted by other processes or I/O traffic." This meant that simply repeating the same set of inputs across multiple runs of the flight simulator would not be guaranteed to give the same results. The researchers hoped that the work they had done in addressing this problem would later be applicable to real-world situations, such as the effects of varying wind conditions on a plane.

See also

Related Research Articles

<span class="mw-page-title-main">IRIX</span> Computer operating system

IRIX is a discontinued operating system developed by Silicon Graphics (SGI) to run on the company's proprietary MIPS workstations and servers. It is based on UNIX System V with BSD extensions. In IRIX, SGI originated the XFS file system and the industry-standard OpenGL graphics API.

<span class="mw-page-title-main">Silicon Graphics</span> 1981–2009 American computing company

Silicon Graphics, Inc. was an American high-performance computing manufacturer, producing computer hardware and software. Founded in Mountain View, California, in November 1981 by James Clark, its initial market was 3D graphics computer workstations, but its products, strategies and market positions developed significantly over time.

<span class="mw-page-title-main">GeForce</span> Brand of GPUs by Nvidia

GeForce is a brand of graphics processing units (GPUs) designed by Nvidia and marketed for the performance market. As of the GeForce 40 series, there have been eighteen iterations of the design. The first GeForce products were discrete GPUs designed for add-on graphics boards, intended for the high-margin PC gaming market, and later diversification of the product line covered all tiers of the PC graphics market, ranging from cost-sensitive GPUs integrated on motherboards, to mainstream add-in retail boards. Most recently, GeForce technology has been introduced into Nvidia's line of embedded application processors, designed for electronic handhelds and mobile handsets.

<i>Microsoft Flight Simulator</i> Windows-based flight simulator software

Microsoft Flight Simulator is a series of flight simulator programs for MS-DOS, Classic Mac OS, and Microsoft Windows operating systems. It was an early product in the Microsoft application portfolio and differed significantly from Microsoft's other software, which was largely business-oriented. Microsoft Flight Simulator is Microsoft's longest-running software product line, predating Windows by three years, and is one of the longest-running video game series of all time.

OpenGL Performer, formerly known as IRIS Performer and commonly referred to simply as Performer, is a commercial library of utility code built on top of OpenGL for the purpose of enabling hard real-time visual simulation applications. OpenGL Performer was developed by SGI. OpenGL Performer is available for IRIX, Linux, and several versions of Microsoft Windows. Both ANSI C and C++ bindings are available.

IRIS GL is a proprietary graphics API created by Silicon Graphics (SGI) in the early 1980s for producing 2D and 3D computer graphics on their IRIX-based IRIS graphical workstations. Later SGI removed their proprietary code, reworked various system calls, and released IRIS GL as the industry standard OpenGL.

<span class="mw-page-title-main">SGI Indy</span> 1993 graphics workstation computer

The Indy, code-named "Guinness", is a low-end multimedia workstation introduced on July 12, 1993 by Silicon Graphics Incorporated (SGI). SGI developed, manufactured, and marketed Indy as the lowest end of its product line, for computer-aided design (CAD), desktop publishing, and multimedia markets. It competed with Intel x86 computers, and with Windows and Macintosh, including using their files and running their applications via software emulation. It is the first computer to come standard with a video camera, called IndyCam.

Core Image is a pixel-accurate, near-realtime, non-destructive image processing technology in Mac OS X. Implemented as part of the QuartzCore framework of Mac OS X 10.4 and later, Core Image provides a plugin-based architecture for applying filters and effects within the Quartz graphics rendering layer. The framework was later added to iOS in iOS 5.

<span class="mw-page-title-main">SGI Indigo</span> Workstations family by Silicon Graphics

The Indigo, introduced as the IRIS Indigo, is a line of workstation computers developed and manufactured by Silicon Graphics, Inc. (SGI). SGI first announced the system in July 1991.

<span class="mw-page-title-main">IRIX Interactive Desktop</span> Computer software desktop environment

IRIX Interactive Desktop is a discontinued desktop environment normally used as the default desktop on Silicon Graphics workstations running IRIX. The IRIX Interactive Desktop uses the Motif widget toolkit on top of the X Window System found on most Unix systems. The default window manager on the IRIX Interactive Desktop is 4Dwm.

<span class="mw-page-title-main">Kurt Akeley</span> American computer graphics engineer

Kurt Akeley is an American computer graphics engineer.

Microsoft Flight Simulator began as a set of articles on computer graphics, written by Bruce Artwick throughout 1976, about flight simulation using 3-D graphics. When the editor of the magazine told Artwick that subscribers were interested in purchasing such a program, Artwick founded Sublogic Corporation to commercialize his ideas. At first the new company sold flight simulators through mail order, but that changed in January 1979 with the release of Flight Simulator (FS) for the Apple II. They soon followed this up with versions for other systems and from there it evolved into a long-running series of computer flight simulators.

<i>Microsoft Flight Simulator X</i> Flight simulation computer game

Microsoft Flight Simulator X (FSX) is a 2006 flight simulation video game originally developed by Aces Game Studio and published by Microsoft Game Studios for Microsoft Windows. It is the sequel to Microsoft Flight Simulator 2004 and the tenth installment of the Microsoft Flight Simulator series, which was first released in 1982. It is built on an upgraded graphics rendering engine, showcasing DirectX 10 features in Windows Vista and was marketed by Microsoft as the most important technological milestone in the series at the time. FSX is the first version in the series to be released on DVD media.

Xsgi is the X Window System (X11) server for the IRIX-based graphical workstations and servers from Silicon Graphics (SGI). Xsgi was released in 1991 with IRIX 4.0 on the SGI Indigo workstation.

Online games are video games played over a computer network. The evolution of these games parallels the evolution of computers and computer networking, with new technologies improving the essential functionality needed for playing video games on a remote server. Many video games have an online component, allowing players to play against or cooperatively with players across a network around the world.

The SGI IRIS series of terminals and workstations from Silicon Graphics was produced in the 1980s and 1990s. IRIS is an acronym for Integrated Raster Imaging System.

The GeForce 10 series is a series of graphics processing units developed by Nvidia, initially based on the Pascal microarchitecture announced in March 2014. This design series succeeded the GeForce 900 series, and is succeeded by the GeForce 16 series and GeForce 20 series using the Turing microarchitecture.

<i>Ace</i> (video game) 1985 video game

Ace is a combat flight simulator video game published for the Commodore 64, VIC-20, and Plus/4 in 1985 by Cascade Games. It was ported to the Amstrad CPC, Amstrad PCW, Amiga, and ZX Spectrum.

<i>Microsoft Flight Simulator</i> (2020 video game) 2020 amateur flight simulator

Microsoft Flight Simulator is a flight simulation video game developed by Asobo Studio and published by Xbox Game Studios. It is an entry in the Microsoft Flight Simulator series which began in 1982, and was preceded by Microsoft Flight Simulator X in 2006. The game is a return of the series after 14 years, with development beginning six years prior to its release. It was released on August 18, 2020, for Windows, with a virtual reality (VR) version released in December of the same year as part of the free Sim 2 update. Microsoft Flight Simulator is the first game in the series to see a VR and console release, with it being released on the Xbox Series X and Series S on July 27, 2021.

Airfight is an early 3D graphics-based multi-user flight simulator, created on the University of Illinois Urbana-Champaign (UIUC) Control Data Corporation (CDC) PLATO system in the early 1970s.

References

  1. 1 2 3 4 5 6 7 8 9 Singhal, Sandeep; Zyda, Michael (1999). Networked Virtual Environments: Design and Implementation. Addison Wesley. ISBN   0201325578.
  2. 1 2 3 4 5 6 Zyda, Michael (2000). "Networked Virtual Environments in 75 Minutes!" (PDF). Archived (PDF) from the original on 17 April 2019. Archived 17 August 2022 at archive.today
  3. 1 2 3 4 5 6 7 8 "IRIX 6.5 Man Pages: FLIGHT(6D)". Archived from the original on 19 January 2016.
  4. 1 2 "Silicon Graphics Flight Simulator". Archived from the original on 3 March 2016.
  5. 1 2 Tarolli, Gary (28 December 1989). "test missile cones in dog/flight?". Archived from the original on 20 August 2022.
  6. 1 2 3 Smith, Roger (2003). "Evolution of Networked Virtual Environments (relevant text is concealed by the second image on the first page. To read it, highlight the whole of that page, then copy-paste into a text editor.)" (PDF). Archived (PDF) from the original on 17 August 2022.
  7. ↑ Millman, Miq (22 November 1988). "dog, radar, shadow, etc. & tcp/ip". Archived from the original on 20 August 2022.
  8. 1 2 Mace, Rob (8 December 1988). "Dogfight and others". Archived from the original on 20 August 2022.
  9. ↑ Moore, Matthew (23 November 1988). "dog, radar, etc". Archived from the original on 20 August 2022.
  10. 1 2 "IRIS users discussion list archive, 1988". Archived from the original on 17 July 2007.
  11. ↑ Mace, Rob (6 December 1988). "dog and arena". Archived from the original on 20 August 2022.
  12. ↑ "dog on IRIS 3130". 14 July 1989. Archived from the original on 20 August 2022.
  13. ↑ Seto, Keith (11 October 1990). "sources for GL demo programs". Archived from the original on 20 August 2022.
  14. ↑ Moore, Matthew (6 December 1988). "Dogfight and Arena". Archived from the original on 20 August 2022.
  15. 1 2 "Why is my SGI multicasting to SGI-DOG.MCAST.NET?". August 1994. Archived from the original on 7 May 2022. Archived 7 May 2022 at the Wayback Machine
  16. ↑ "What is sending packets to the sgi-dog.mcast.net multicast address?". Archived from the original on 10 June 2021.
  17. ↑ Mapleson, Ian. "UNIX Administration Course: Detailed Notes for Day 2". Archived from the original on 10 March 2021.
  18. ↑ "Multicasting from workstations to SGI-DOG". February 1995. Archived from the original on 7 May 2022. Archived 20 August 2022 at archive.today
  19. ↑ "DOG: diff for point-to-point communication". 20 September 1989. Archived from the original on 20 August 2022.
  20. ↑ Natalie, Ron. "Re: [TUHS] Gaming on early Unix". The Unix Heritage Society mailing list. Archived from the original on 20 August 2022.
  21. ↑ "Ronald Natalie". LinkedIn.
  22. ↑ Hobson, Kevin (7 December 1988). "Dogfight and others". Archived from the original on 20 August 2022.
  23. ↑ Dombroski, Robert M. (28 November 1988). "DOG". Archived from the original on 20 August 2022.
  24. ↑ "dog, radar, shadow, etc. & tcp/ip". 29 November 1988. Archived from the original on 20 August 2022.
  25. ↑ "Summary: Flight simulators under X". 16 November 1992. Archived from the original on 24 September 2022.
  26. ↑ "4.1 Pixrect Reference Manual (Part Number: 800-4835-10. Revision A of 5 January, 1990)" (PDF). Archived (PDF) from the original on 3 August 2020. Archived 24 September 2022 at archive.today
  27. 1 2 Hayman, Steve (15 February 1990). "Status of 'flight' source". Archived from the original on 24 September 2022.
  28. ↑ "X-wing model for Dog". 15 October 1993. Archived from the original on 24 September 2022.
  29. ↑ Cole, Ron (21 February 1994). "dogfight / flight". Archived from the original on 24 September 2022.
  30. ↑ Hall, Timothy (16 August 1989). "Overlay planes". Archived from the original on 24 September 2022.
  31. ↑ "Comments/Questions about dog/flight". 16 September 1992. Archived from the original on 24 September 2022.
  32. ↑ "Developer Forum '95 - Speaker Information". Archived from the original on 10 March 2021. Retrieved 23 August 2022. Archived 23 August 2022 at archive.today
  33. 1 2 3 4 Tarolli, Gary (21 February 1989). "flight's concept of a 'good landing'". Archived from the original on 20 August 2022.
  34. ↑ "+-} Question on FLIGHT>Silcon Graphics". 8 June 1991. Archived from the original on 20 August 2022.
  35. ↑ "+-} Question on FLIGHT>Silcon Graphics". 8 June 1991. Archived from the original on 20 August 2022.
  36. ↑ Tarolli, Gary (11 June 1991). "+-} Question on FLIGHT>Silcon Graphics". Archived from the original on 20 August 2022.
  37. 1 2 Jevans, David (20 February 1989). "dog's T". Archived from the original on 20 August 2022. Archived 20 August 2022 at the Wayback Machine
  38. ↑ Tarolli, Gary (21 October 1991). "Question about SGI flight simulator". Archived from the original on 24 September 2022.
  39. ↑ Tarolli, Gary (27 February 1992). "Flight/dog". Archived from the original on 24 September 2022.
  40. ↑ "Flight & Dogfight". 21 May 1993. Archived from the original on 7 May 2022. Archived 7 May 2022 at archive.today
  41. ↑ Gigante, Mike A. (23 February 1989). "flight's concept of a 'good landing'". Archived from the original on 20 August 2022.
  42. ↑ Tarolli, Gary (25 February 1989). "flight's concept of a 'good landing'". Archived from the original on 20 August 2022.
  43. 1 2 Frost, Jim (22 February 1989). "flight's concept of a 'good landing'". Archived from the original on 20 August 2022.
  44. ↑ Bartels, Richard (22 February 1989). "flight's concept of a 'good landing'". Archived from the original on 20 August 2022.
  45. ↑ Tarolli, Gary (22 February 1989). "flight's concept of a 'good landing'". Archived from the original on 20 August 2022.
  46. ↑ VandeWettering, Mark (22 February 1989). "Flight Simulators... (was concept of good landing)". Archived from the original on 20 August 2022.
  47. ↑ Cadiz, Jorge; Ouyang, Ruey; Thompson, Jack (5 October 1989). Interfacing of the Silicon Graphics Networkable Flight Simulator with SIMNET (PDF) (Technical report). University of Central Florida, Institute for Simulation and Training. IST-TR-89-1. Archived (PDF) from the original on 22 July 2022.
  48. ↑ Dahn, David A. (1 December 1990). A Low-Cost Part-Task Flight Training System: An Application of a Head Mounted Display (PDF) (MSc). Air Force Institute of Technology. Archived (PDF) from the original on 22 July 2022.
  49. ↑ Simpson, Dennis J. (1 December 1991). An Application of the Object-Oriented Paradigm to a Flight Simulator (MSc). Air Force Institute of Technology.
  50. ↑ Sammut, Claude; Hurst, Scott; Kedzier, Dana; Michie, Donald (1992). "Learning to Fly" (PDF). In Derek Sleeman; Peter Edwards (eds.). Machine Learning: Proceedings of the Ninth International Workshop (ML92). Morgan Kaufman. pp. 385–393. doi:10.1016/B978-1-55860-247-2.50055-3. Archived (PDF) from the original on 2 June 2021.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.