UW EXTENSION CERTIFICATE PROGRAM IN GAME DEVELOPMENT 2 ND QUARTER: ADVANCED GRAPHICS The asset pipeline

Goals 1. Learn the value of a well crafted asset pipeline 2. Review implementation strategies

Game development process  Four stages:  Prototyping  Technology development  Production  Release  Production stage: at least 50% of time and effort  Driven by designers and artists, not programmers  Programmers must ensure production can be sustained  Technology development must be done accordingly

Graphics production  Driven by artists… mostly  Designers drive “what”, artists drive “how”  Programmers define the limitations  Vertex density in the meshes  Resolution of the textures  Size of the textures in memory (compressed formats)  Bone counts, units of measurement, material features…  Programmers also create the tools  Exporters/importers, converters, packers/unpackers

The ideal toolchain  Designers/artists generate a ton of asset files  Using exporters and editors  Game can use those files directly  Reloading them on the fly when they change Fast iteration!  One tool or batch of tools packs/optimizes assets  Game can use the packed/optimized assets  Individual files can override them Fast game and fast iteration

Archives/pack files  Like ZIP files  Sometimes, they are actual ZIP files  Often different, with a separate TOC (Table Of Contents)  Use them instead of using individual files  Lay out all assets smartly to reduce disk seeking  Improve read speed by using compression Zlib is a common choice

Terrain/environment  Static geometry: floor, walls, ceiling  Textures, materials and lighting  Also decorative meshes, like lampposts  Also triggers, navigation maps, attach points  Height map, BSP, arbitrary mesh, portals…  Static vs. streaming  Breakable environments  Usually done by mesh substitution  Typically very homogeneous

Terrain/environment toolchain  Editors for BSPs, portals, level object placement…  Also partitioning and layout for streaming  Exporters for textures, meshes, materials…  Usually created with 3 rd party tools  Converters  Images into heightmaps  Texture and material/shader packers  Development assets into optimized  Stitch environment chunks  Radiosity lightmap generators

Characters  Cars, animals, monsters, people…  Textures, materials, meshes, skeletons…  Animations, poses, transitions  Programmer must provide all limitations  Physics substitute animations with code  AI scripts and gameplay parameters  Lots of variation

Character toolchain  Everything typically edited in 3 rd party tools  Exporters for everything  Not everything: game can use standard file formats  Converters  Animation keyframing/optimizing/matching  Parsers/compilers for scripts and description files

Special effects  Particle systems  Hopefully, data-driven and with an editor tool  Full-screen post-processing  Decals  Skyboxes

Miscellaneous  Fonts  Possibly including Chinese, Japanese, Korean Using limited vocabularies?  Backgrounds, icons, 2D animations, etc…