Path tracing is a computer graphics method of rendering images of three dimensional scenes such that the global illumination is faithful to reality. Fundamentally, the algorithm is integrating over all the illuminance arriving to a single point on the surface of an object. This illuminance is then reduced by a surface reflectance function to determine how much of it will go towards the viewpoint camera. This integration procedure is repeated for every pixel in the output image. When combined with physically accurate models of surfaces, accurate models of real light sources (light bulbs), and optically-correct cameras, path tracing can produce still images that are indistinguishable from photographs.
Path tracing naturally simulates many effects that have to be specifically added to other methods (conventional ray tracing or scanline rendering), such as soft shadows, depth of field, motion blur, caustics, ambient occlusion, and indirect lighting. Implementation of a renderer including these effects is correspondingly simpler.
Due to its accuracy and unbiased nature, path tracing is used to generate reference images when testing the quality of other rendering algorithms. In order to get high quality images from path tracing, a large number of rays must be traced to avoid visible noisy artifacts.
Read more about Path Tracing: History, Description, Bidirectional Path Tracing, Performance, Scattering Distribution Functions, In Real Time, Notes
Famous quotes containing the words path and/or tracing:
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—E.B. (Elwyn Brooks)
“In mind, she was of a strong and vigorous turn, having from her earliest youth devoted herself with uncommon ardour to the study of the law; not wasting her speculations upon its eagle flights, which are rare, but tracing it attentively through all the slippery and eel-like crawlings in which it commonly pursues its way.”
—Charles Dickens (1812–1870)