Lightmap
A lightmap is a data structure that is used in lightmapping ; a form of surface caching in which the brightness of surfaces from virtual environments is precalculated and stored in texture maps for later use. Lightmaps are mostly applied to static objects in real-time 3D environment software, such as video games , to enable lighting effects such as global lighting without a great deal of computation.
history
John Carmack's Quake was the first computer game to use lightmaps to enhance rendering . Before lightmaps were invented, real-time applications used only Gouraud shading to interpolate vertex lighting for surfaces. This enabled only a small amount of lighting information and produced clipping artifacts in the vicinity of the camera without perspective-correct interpolation. The Diskontinuitätsvernetzung was sometimes especially in radiosity used for adaptive solutions improve the resolution of vertices lighting information, but with the additional computational effort for the primitive device for real-time screening were generally prohibitive. Quake's software renderer used surface caching to apply lighting calculations in texture space once, when polygons initially appear within the field of view (effectively creating temporary "lighted" versions of the currently visible textures while the viewer was negotiating the scene).
As openly available 3D graphics hardware capable of multitexturing , light mapping became increasingly popular, and engines began to incorporate lightmaps in real time as a secondary multi-aperture texture layer.
Individual evidence
- ↑ Quake's Lighting Model: Surface Caching. Retrieved September 9, 2017 .