{"id":26658,"date":"2018-06-19T15:03:00","date_gmt":"2018-06-19T15:03:00","guid":{"rendered":"http:\/\/www.gamasutra.com\/view\/news\/320206"},"modified":"2018-06-19T15:03:00","modified_gmt":"2018-06-19T15:03:00","slug":"blog-using-prefabs-in-game-development","status":"publish","type":"post","link":"https:\/\/sickgaming.net\/blog\/2018\/06\/19\/blog-using-prefabs-in-game-development\/","title":{"rendered":"Blog: Using prefabs in game development"},"content":{"rendered":"

The following blog post, unless otherwise noted, was written by a member of Gamasutra\u2019s community.
The thoughts and opinions expressed are those of the writer and not Gamasutra or its parent company. <\/small><\/i><\/strong> <\/p>\n

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Prefabs are not a new topic to game developers. These\u00a0will be referenced in future articles of mine, so here’s an overview to a concept for\u00a0mastering massive content.<\/em><\/p>\n

If you\u2019ve ever had to deal with tons of objects across multiple scenes, you\u2019ll inevitably wish you could\u00a0group similar or exact copies together for quicker management.\u00a0If you\u2019ve added a desk lamp to 30 different office rooms in 15 different scenes, wouldn’t\u00a0it be nice to turn up the that\u00a0light’s intensity\u00a0once instead of 450<\/em><\/strong> times?<\/p>\n

That\u2019s the power of prefabs.\u00a0<\/strong><\/em><\/p>\n

So, what exactly is a prefab?\u00a0It’s a collection of game objects used in multiple places\u00a0across the game. It’s a concept I’ve made sure to use across past projects like Six Days in Fallujah<\/em>, Prey 2<\/em>, and Mafia 3<\/em>.<\/p>\n

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\nA Prefab<\/strong>\u00a0should be\u00a0a Scene<\/strong>.\u00a0The only thing that should\u00a0make\u00a0a prefab different than a scene (a level, map, environment, etc.)\u00a0is it exists inside<\/u> a scene.\u00a0A large city scene can have several small prefab neighborhoods and those in turn can have repeatable prefab houses inside of each.<\/p>\n

Some game engines develop prefabs as a unique feature, separate from a scene’s format. By developing a prefab as an extension of a classic scene means they inherit all features and power scene editing\u00a0has!<\/p>\n

Any feature that exists for a scene should exist for a prefab:<\/p>\n

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  • A collection of models (a bench, a bus stop sign, a garbage can).<\/li>\n

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  • A building with AI navigation and interaction nodes.<\/li>\n

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  • An enemy with a unique change (BadGuy_Type_4 with dual pistols).<\/li>\n

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  • A complex script sequence (depending on project’s\u00a0script file handling).<\/li>\n

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  • A skybox with all associated FX and animation.<\/li>\n

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  • A Security Door (a door model & logic, security palm switch & logic, emergency lighting & logic, surrounded by cover nodes & path volumes).<\/li>\n

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    Advantages<\/h2>\n
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    1. Repeat occurrences only have to be created once.\u00a0When the original prefab is modified, all instances are updated.
      \u00a0<\/li>\n

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    2. Multiple people can work on the same scene by partitioning\u00a0the scene into prefabs.\u00a0Each user works on their individual prefab, testing their work in the\u00a0master scene.<\/li>\n

      \n<\/ol>\n

      Game Usage<\/h2>\n

      Prefabs should be\u00a0created in the editor as a new scene or from a selection within an existing scene. The most common type is a Static Prefab<\/em><\/strong>. They can be saved to the game library for reuse later.\u00a0When the game is built and run, all static prefabs are ungrouped (sometimes called exploded). All parts should have their name prefixed to the prefab’s unique name for reference. All game logic now points to unique items\u00a0maintaining unique scripting.<\/p>\n

      In the editor they can also be exploded\u00a0into an existing scene to\u00a0creating unique, free roaming\u00a0objects, no longer connected to its source.\u00a0\u00a0<\/p>\n

      Aside from static prefabs, Dynamic Prefabs<\/strong><\/em> are another option.\u00a0These are used to stream\u00a0in content. If done right, prefabs can\u00a0be the primary means all content is contained and streamed into the game.<\/p>\n

      With procedural systems like Houdini<\/strong><\/em>, you could even extend prefabs into becoming\u00a0Smart Prefabs<\/strong><\/em>.\u00a0These feature a set of rules to decide what, where, and when to place a variety objects at different times.\u00a0This article is only about the core prefab concept though.<\/p>\n

      Every scene can be made with a number of prefabs.\u00a0 Take a look at the following diagram as an example:<\/p>\n

      \"\"<\/p>\n

      Now let’s see how prefabs let several people work on the scene:\u00a0<\/p>\n

      \"\"<\/p>\n

      The Art Team works on the Ground\u00a0Terrain A<\/strong> location:<\/p>\n