Id Tech 4 resulted in the obsolescence of DirectX 7.0 graphics chips such as the widespread GeForce 2 and Radeon 7200, as well as DirectX 6.0 chipsets such as RIVA TNT2 and Rage 128, and software rendering (with an integrated Intel GMA). By E3 2002, the recommended GPU was the Radeon 9700 while its DirectX 9.0 features are not necessary to render the game, its advanced architecture, 256-bit memory bus, and efficiency were needed to run Doom 3 at high detail and playable speed. Other important features of Doom 3 engine are normal mapping and specular highlighting of textures, realistic handling of object physics, dynamic, ambient soundtrack and multi-channel sound.Ī disadvantage of id Tech 4 was that it needed a high-end graphics processing unit (GPU), which was at least DirectX 8.0 compliant with fully programmable vertex and pixel shaders, such as the Nvidia GeForce 3 or ATI Radeon 8500, with 64 MB of VRAM. This allowed an in-game computer terminal to perform more than one function, such as a readily apparent door-unlocking button, combined with a more obscure function allowing an astute player to unlock a nearby weapons locker. Rather than using a simple "use key", the crosshair acts as a mouse cursor over the screens allowing the player to use a computer in the game world. To increase the interactivity with the game-world, id designed hundreds of high-resolution animated screens for in-game computers. To create a more movie-like atmosphere, id interspersed the gameplay with many in-game animated sequences of monsters ambushing the player or just lurking around. A shortcoming of this approach is the engine's inability to render soft shadows and global illumination.Īs well as dynamic lighting and shadows, the Doom 3 engine was id Software's first to make extensive use of bump mapping. This allows lights to cast shadows even on non-static objects such as monsters or machinery, which was impossible with static lightmaps. By contrast in the new Doom 3 engine, most light sources are computed on the fly. All 3D engines up to and including Quake III and Unreal Tournament had computed or rendered lightmaps during map creation, saving that information in the map data, which made the lighting extremely static. The key advance of the Doom 3 graphics engine is the unified lighting and shadowing.
0 Comments
Leave a Reply. |