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:
“She’s in the house.
She’s at turn after turn.
She’s behind me.
She’s in front of me.
She’s in my bed.
She’s on path after path,
and I’m weak from want of her.
O heart,
there is no reality for me
other than she she
she she she she
in the whole of the reeling world.
And philosophers talk about Oneness.”
—Amaru (c. seventh century A.D.)
“Our life is a faint tracing on the surface of mystery, like the idle, curved tunnels of leaf miners on the face of a leaf. We must somehow take a wider view, look at the whole landscape, really see it, and describe what’s going on here. Then we can at least wail the right question into the swaddling band of darkness, or, if it comes to that, choir the proper praise.”
—Annie Dillard (b. 1945)