Project 2010, Project 2013, and Project 2016 all use the same file format. For example, a project created in Project 2016 can be opened in Project 2010 without saving the project to a different format.
Portal was acclaimed as one of the most original games of 2007, despite criticisms for its short duration and limited story. It received praise for its originality, unique gameplay and dark story with a humorous series of dialogue. GLaDOS, voiced by Ellen McLain in the English-language version, received acclaim for her unique characterization, and the end credits song "Still Alive", written by Jonathan Coulton for the game, was praised for its original composition and humorous twist. Portal is often cited as one of the greatest video games ever made. Excluding Steam download sales, over four million copies of the game have been sold since its release, spawning official merchandise from Valve including plush Companion Cubes, as well as fan recreations of the cake and portal gun.
The austere settings in the game came about because testers spent too much time trying to complete the puzzles using decorative but non-functional elements. As a result, the setting was minimized to make the usable aspects of the puzzle easier to spot, using the clinical feel of the setting in the film The Island as reference. While there were plans for a third area, an office space, to be included after the test chambers and the maintenance areas, the team ran out of time to include it. They also dropped the introduction of the Rat Man, a character who left the messages in the maintenance areas, to avoid creating too much narrative for the game, though the character was developed further in a tie-in comic "Lab Rat", that ties Portal and Portal 2's story together. According to project lead Kim Swift, the final battle with GLaDOS went through many iterations, including having the player chased by James Bond lasers, which was partially applied to the turrets, Portal Kombat where the player would have needed to redirect rockets while avoiding turret fire, and a chase sequence following a fleeing GLaDOS. Eventually, they found that playtesters enjoyed a rather simple puzzle with a countdown timer near the end; Swift noted, "Time pressure makes people think something is a lot more complicated than it really is", and Wolpaw admitted, "It was really cheap to make [the neurotoxin gas]" in order to simplify the dialogue during the battle.
The Weighted Companion Cube inspiration was from project lead Kim Swift with additional input from Wolpaw from reading some "declassified government interrogation thing" whereby "isolation leads subjects to begin to attach to inanimate objects"; Swift commented, "We had a long level called Box Marathon; we wanted players to bring this box with them from the beginning to the end. But people would forget about the box, so we added dialogue, applied the heart to the cube, and continued to up the ante until people became attached to the box. Later on, we added the incineration idea. The artistic expression grew from the gameplay." Wolpaw further noted that the need to incinerate the Weighted Companion Cube came as a result of the final boss battle design; they recognized they had not introduced the idea of incineration necessary to complete the boss battle, and by training the player to do it with the Weighted Companion Cube, found the narrative "way stronger" with its "death". Swift noted that any similarities to psychological situations in the Milgram experiment or 2001: A Space Odyssey are entirely coincidental.
Most of the soundtrack is non-lyrical ambient music composed by Kelly Bailey and Mike Morasky, somewhat dark and mysterious to match the mood of the environments. The closing credits song, "Still Alive", was written by Jonathan Coulton and sung by Ellen McLain (a classically-trained operatic soprano) as the GLaDOS character. A brief instrumental version of "Still Alive" is played in an uptempo Latin style over radios in-game. Wolpaw notes that Coulton was invited to Valve a year before the release of Portal, though it was not yet clear where Coulton would contribute. "Once Kim [Swift] and I met with him, it quickly became apparent that he had the perfect sensibility to write a song for GLaDOS." The use of the song over the closing credits was based on a similar concept from the game God Hand, one of Wolpaw's favorite titles. The song was released as a free downloadable song for the music video game Rock Band on April 1, 2008. The soundtrack for Portal was released as a part of The Orange Box Original Soundtrack.
Portal was first released as part of The Orange Box for Windows and Xbox 360 on October 10, 2007, and for the PlayStation 3 on December 11, 2007. The Windows version of the game is also available for download separately through Valve's content delivery system, Steam, and was released as a standalone retail product on April 9, 2008. In addition to Portal, the Box also included Half-Life 2 and its two add-on episodes, as well as Team Fortress 2. Portal's inclusion within the Box was considered an experiment by Valve; having no idea of the success of Portal, the Box provided it a "safety net" via means of these other games. Portal was kept to a modest length in case the game did not go over well with players.
Portal is the first Valve-developed game to be added to the OS X-compatible list of games available on the launch of the Steam client for Mac on May 12, 2010, supporting Steam Play, in which buying the game on Macintosh or Windows computer makes it playable on both. As part of the promotion, Portal was offered as a free game for any Steam user during the two weeks following the Mac client's launch. Within the first week of this offer, over 1.5 million copies of the game were downloaded through Steam. A similar promotion was held in September 2011, near the start of a traditional school year, encouraging the use of the game as an educational tool for science and mathematics. Valve wrote that they felt that Portal "makes physics, math, logic, spatial reasoning, probability, and problem-solving interesting, cool, and fun", a necessary feature to draw children into learning. This was tied to Digital Promise, a United States Department of Education initiative to help develop new digital tools for education, and which Valve is part of.
This paper introduces brainstorming games developed for the use of game designers. Three gamesdesigned especially for generating new game ideas were developed in the GameSpace project, whichstudies methods for design and evaluation of casual mobile multiplayer games. GameSpace ideageneration games have been developed through an iterative process in collaboration with the end users:game industry professionals. According to our workshop experiences and tentative results from a pilotstudy, idea generation games can be successful devices for the creative work of game designers. Gamebasedidea generation techniques provide an easily facilitated, focused yet playful setting for coming upwith new ideas. However, our experiences indicate that idea generation games feature special challengesthat must be taken into consideration when designing such games.
This syllabus is for a game design course whose goal is to use rapid paper prototyping to develpe 10 paper-based games in 10 weeks (students make one game per week). It is unclear what age group this syllabus was written for but it is sufficiently challenging to prove useful for this research group's purposes. When applied this group decided to use weeks 7 & 8 to iterate, revise, refine and improve the gameplay and production values of their best game produced during the earlier weeks. They expressed a desier to complete a polished project. They found the enforced rapid prototyping to be exhausting and were seeking tangible rewards. The materials used were a sketch book, paper of various sizes and generic game pieces and tokens. Formal and conceptual restrictions were placed on each iteration of the game development to guide and challenge the students, for example:
 This project is a set of alernate rules in book/e-book, iPhone app or printed card form that use the boards and pieces of traditional games like Monopoly, Trivial Pursuit, Scrabble, and Clue to make up new games. While not strictly a design tool it is a good example of how existing popular games can be remixed to create new games.
Aldrich, ClarkBook jacket review/blurb: "Designed for learning professionals and drawing on both game creators and instructional designers, Learning by Doing explains how to select, research, build, sell, deploy, and measure the right type of educational simulation for the right situation. It covers simple approaches that use basic or no technology through projects on the scale of computer games and flight simulators."
Bogert and Oliver (1945) first recognized the distinct morphology of the southern, Sinaloan lineage of G. morafkai, but they were unable to quantify it due to very small sample sizes. Other studies have also noted morphological characteristics that distinguish the Sinaloan lineage but did not provide a quantitative analysis (Loomis and Geest 1964; Hardy and McDiarmid 1969; Germano 1993; Fritts and Jennings 1994; Berry et al. 2002; Bury et al. 2002; Legler and Vogt 2013). We observed distinct morphological characters in 23 tortoises in the vicinity of Alamos, Sonora in 2005. To this, we added anecdotal observations and measurements of several preserved specimens of Sonoran and Sinaloan lineages of G. morafkai and G. agassizii in the University of Arizona herpetological collection and data from McLuckie et al. (1999). Consequently, we developed a suite of measurements and qualitative factors that morphologically diagnose the Sinaloan lineage. Measurements (in mm) included the following 37 variables: mid-carapace length (MCL); maximum width; maximum width at 3/4 marginal scute seam; maximum width at mid-6th marginal; maximum width at 7/8 marginal scute seam; width of C-truss 1 (left); width between anal tips; rear foot-pad greatest width; maximum height; height at 2nd vertebral scute; height at 3rd vertebral scute; height at 4th vertebral scute; maximum plastron length from tip of gular horn to tip of anal scutes; length of plastron truss (left); length of plastron shortest diagonal; length of right pectoral scute; length of left pectoral scute; average midline length of abdominal scutes; average midline length of femoral scutes; average midline length of anal scutes; depth of male concavity; distance of posterior shell opening from anal tip to carapace; distance of supracaudal scute to anal notch; distance of mid-9th marginal to inner femoral; distance of mid-9th marginal to outer femoral; distance of anterior shell opening; distance of nuchal to plastron; distance of mid-2nd marginal to humeral (inner and outer); distance of gular straight-line length; distance of curved length; head length from tip of rostrum to anterior corner of the eye; width of tympanum; height of bridge from 6th marginal to abdominal scutes; shortest bridge length; distance of anterior bridge opening to inner 2nd/3rd marginal scute seam; distance of anterior bridge opening to outer 2nd/3rd marginal scute seam; and distance from bridge to inguinal point of attachment. We took straight-line measurements only. We also assessed the following 13 qualitative characters: shape of rear feet (flat/rounded); presence of spur at humeral junction; shape of anterior and posterior armoring scales (rounded/pointed); spikiness of rear and front legs (high/moderate/low); lateral profile of shell (flat/domed); profile of pre-frontals; wear-class of shell; carapace color; plastron color; integument color; annuli distinct (yes/no); and tail length (shorter or same as G. agassizii). 781b155fdc