In the early 1990s a home computer or console could show a detailed picture, or draw a scene in real time, but not both at once. Pre-rendered backgrounds split the difference. The room is made once, in advance, at whatever quality the artists can afford: hand-coloured, or rendered for minutes or hours on a graphics workstation. The game ships only the finished picture and draws its characters over it, live, from a camera that matches the one the picture was made from.
The results looked a generation ahead of the hardware. When Nintendo showed Donkey Kong Country in 1994, Edge reported that the audience took it for a game for Nintendo’s next console. Final Fantasy VII’s backgrounds, Edge said in 1997, had made Square “SGI’s largest desktop customer”. The price was paid in the camera. A picture cannot turn round, so every angle had to be chosen by the designers, and players spent the decade arguing about whether the choices helped or hindered them.
Fast facts
- The idea: a finished image for the scenery, live polygon or sprite characters on top, and a camera fixed to match.
- Alone in the Dark (PC, November 1992): 170 hand-coloured images for 170 camera positions.
- Myst (1993): “Each scene is presented as a 3-D rendered, stationary backdrop” (Computer Gaming World, December 1993).
- Donkey Kong Country (SNES, 1994): “Everything in the game — the sprites, the backgrounds and the 6,000+ frames of animation — is rendered” (Edge, September 1994).
- Resident Evil (PlayStation, 1996): planned in full 3D, switched to pre-rendering because the hardware could not draw it.
- Final Fantasy VII (PlayStation, 1997): “prerendered backdrops inhabited by realtime 3D Gouraud-shaded characters” (Edge, March 1997).
- The cost: a fixed camera, scenery that cannot change, and characters that can look out of place against the art.
How it works
The background is an image, not a model. If the scene was built in 3D, it can be as detailed as the artists like, with lighting, texture and thousands of surfaces, because it is rendered once, offline, and never again. What reaches the player is a screenful of pixels.
The characters are live. In a 3D game they are polygon models, transformed and drawn every frame through a virtual camera placed where the picture’s camera was, with the same position, direction and lens. Get that match right and a character standing on the painted floor appears to stand on the floor. When the character walks out of shot, the game cuts to another picture from another camera.
Because the picture contains no geometry, the game has to be told about it separately. It needs invisible data for where characters can walk, and it needs a way to put scenery in front of a character: a pillar a hero walks behind, a table edge that should hide her legs. The simplest approach draws the backdrop, then the characters, then foreground pieces of the picture cut out and drawn last. A modern analysis of Final Fantasy VII describes its backgrounds as cut into tiles, each given a draw order, so that the player can move in front of and behind objects. Whatever the method, every occluding object in every picture is extra work for the artists.
A related trick applies the same idea to sprites. Instead of drawing a character live, the artists render its animation frames in advance from a 3D model and store them as ordinary bitmaps. That was how Donkey Kong Country worked on the Super Nintendo.
Alone in the Dark
Frédérick Raynal’s horror game for Infogrames came out for the PC in November 1992, and its rooms were built by a method halfway between drawing and rendering. Edge’s history of the game in 2005 described a tool, written with a trainee, Frank De Girolami, that could place a camera inside a scene, generate the scene in wireframe and capture it as a bitmap. A graphic designer then had to “colour by hand” the wireframe. Because the picture was traced from the same geometry the game used, the polygon characters and the painted room agreed about where the walls and floor were. Raynal’s plan for the game listed “170 images for 170 different cameras”.
Chris Lombardi’s Computer Gaming World preview in February 1993 described the two halves of the result. The characters were “composed of simple geometric shapes… the result is rather rough”. The cameras were what impressed him: “As one’s character moves about a room, one’s perspective will change many times; from a straight-away side-on pan, to an overhead ‘closet-set’ shot, to an ‘insect-view’ from floor level, to many other perspectives in the visual grammar of cinema. While many rooms have only two such camera views, some have up to nine!” He also named the cost: “Swift changes in the viewpoint can occasionally be disastrous when the player’s character is in combat mode.”
Myst
Myst, in 1993, took the pictures without the live characters. “Each scene is presented as a 3-D rendered, stationary backdrop,” Computer Gaming World wrote in December 1993. “Any animation that may occur is contained within QuickTime windows that are seamlessly integrated into that backdrop. Navigation is controlled by clicking on the screen in the direction desired.” There was nobody on screen to line up with the camera: the player was the camera. Rand and Robyn Miller, the magazine said, “chose to use their old buddy HyperCard as the engine to drive Myst.”
Donkey Kong Country
Rare applied the idea to a Super Nintendo platform game. At the Summer Consumer Electronics Show in 1994, Edge reported, Nintendo of America’s chairman Howard Lincoln let the audience watch the demonstration before telling them, “The game you have been watching is Donkey Kong Country for the Super Nintendo.” Everything in it, “the sprites, the backgrounds and the 6,000+ frames of animation”, had been rendered with Alias PowerAnimator on Silicon Graphics workstations. Rare told Edge it had the third largest SGI network in the world, after Boeing and Industrial Light and Magic.
The Super Nintendo could not display those renders directly. Edge explained that the tools rendered backgrounds and sprites in 24-bit colour and then knocked “the colours down to 256 — or even 16 — colours per sprite using optimised colour tables”, and that compression squeezed the result onto one 32-megabit cartridge. The machine was drawing sprites and tiles as it always had; the difference was where the pictures came from. Donkey Kong Country has its own entry.
Resident Evil
Resident Evil was meant to be fully 3D. “Initially it was intended to be a full 3D production,” its director Shinji Mikami told Retro Gamer, “but we had to give up on that idea and modify Biohazard to use pre-rendering.” The PlayStation could not draw the mansion well enough in real time. Motoji Fujita and Ippei Masuda were largely responsible for rendering the backgrounds. The result, Mikami said, was that “the graphics became exceptionally good, though operability was sacrificed to achieve that. It was very difficult to manufacture the characters while reducing their polygon counts to a reasonable level.”
Edge‘s caption for its March 1996 interview with Capcom’s Akio Sakai put it simply: Resident Evil “gels Alone in the Dark gameplay with blood and guts”. The June 1996 review gave it nine out of ten and the sentence the genre has kept: “Resident Evil is Alone in the Dark directed by George A Romero with the design sensibilities of Myst.” It measured the art against Infogrames’ Time Gate, “where the polygon figures look hopelessly inadequate even against backgrounds that boast a fraction of the detail of Resident Evil’s (words alone fail to do justice to the fanatical richness of Resident Evil’s art design, where even the wallpaper and carpets warrant admiring scrutiny)”. It counted the fixed camera as part of the design: “Everything in Resident Evil is geared towards suspense: the skewed camera angles, the haunting strains of the soundtrack, the fact that you can run forwards but only retreat in painfully slow steps.” Mikami used the cameras to hide zombies on purpose; see survival horror and tank controls.
By November 1996 the phrase needed no explanation. Previewing Ecstatica 2, Edge wrote that “the closest modern reference points are probably Time Gate and Time Commando — all three games feature pre-rendered backgrounds”, and of Queen: The Eye, “Using some exquisite prerendered backdrops and realtime polygon characters, Queen looks quite beautiful”.
Final Fantasy VII
Square’s Final Fantasy VII launched in Japan on 31 January 1997 and sold, by Edge’s count, “nearly 2.04m units in just three days”. The magazine found “the incredible prerendered backdrops inhabited by realtime 3D Gouraud-shaded characters are easily the most striking thing about the game (and in the process have made Square SGI’s largest desktop customer)”. The PC conversion of 1998 showed a limit of the method: a picture is made at one resolution. Computer Gaming World noted that “The 3D acceleration affects only the character models, the battle engine, and the overworld map. The prerendered backgrounds are a bit washed out, probably due to monitor-versus-TV resolution problems.”
On the PC
PC adventures reached the same place from the other direction: 2D games adding a polygon lead. Perfect Entertainment described Discworld Noir to PC Zone in November 1998: “It’s not 2D any more, it’s 3D. The backdrops are pre-rendered at a very high resolution, and the main character is rendered in real-time 3D. It’ll all be light-sourced in real-time too.” The lead was “over 2000 polygons”; “Not all the characters will be real-time though”.
Side-scrolling games used the pictures too. Reviewing Heart of Darkness, the long-delayed follow-up by Another World’s designer Éric Chahi, Computer Gaming World wrote in the same month: “Like many side-scrollers, HEART OF DARKNESS uses sprites set on top of prerendered backgrounds. Even so, it’s done quite beautifully, with the well-drawn background art rivaling that of MYST at times”.
What it cost
The reviews that praised the pictures also listed the bills.
- The camera. Designers chose every angle, and the angles could fight the player, as Lombardi found in combat in 1993.
- The controls. Retro Gamer read Mikami’s “operability was sacrificed” as a polite way of describing the clunky movement of the early Resident Evil games.
- The characters. Live polygons had to sit convincingly in detailed art. Edge found Time Gate’s figures “hopelessly inadequate” against its backgrounds.
- The resolution. A background is made for one screen, as Final Fantasy VII’s PC conversion showed.
- The work. Every picture, and every cut-out piece of foreground, had to be made by hand or rendered on expensive hardware; Edge counted 170 cameras in Alone in the Dark and 6,000 rendered frames in Donkey Kong Country.
Sources
- “The Making of… Alone in the Dark”, Edge issue 150, June 2005, pp. 105–107: the camera and wireframe tool, hand colouring, the 170 cameras, the November 1992 release.
- Chris Lombardi, “The Shape of Things to Come”, Computer Gaming World issue 103, February 1993: Alone in the Dark preview.
- Christopher Breen, Myst review, Computer Gaming World issue 113, December 1993.
- Edge issue 12, September 1994, pp. 43–44: Donkey Kong Country at the Summer CES (Lincoln’s announcement, PowerAnimator and SGI, the colour reduction, the cartridge).
- Jonti Davies, “The Making of Resident Evil”, Retro Gamer, reprinted in Retro Gamer Collection volume 4, 2010, pp. 118–123: interview with Shinji Mikami (the switch from full 3D, operability, polygon counts, the background artists, camera blind spots).
- Edge issue 30, March 1996, p. 51: interview with Akio Sakai. Issue 33, June 1996: Resident Evil review, nine out of ten. Issue 38, November 1996: Ecstatica 2 and Queen: The Eye previews.
- Edge issue 43, March 1997: Final Fantasy VII’s Japanese launch.
- Computer Gaming World issue 172, November 1998: Final Fantasy VII PC review; Heart of Darkness review by Thierry Nguyen (its team of Out of This World veterans).
- PC Zone issue 69, November 1998: Discworld Noir preview.
- Justin Meiners and Hunter Rasmussen, “An Adventure in Pre-Rendered Backgrounds” (web, secondary): Final Fantasy VII’s backgrounds cut into tiles with a draw order. https://www.jmeiners.com/pre-rendered-backgrounds/