Ray tracing (graphics)
Videos
In 3D computer graphics, ray tracing is a technique for modeling light transport for use in a wide variety of rendering algorithms for generating digital images.
Dürer woodcut of Jacob de Keyser's invention. With de Keyser's device, the artist's viewpoint was fixed by an eye hook inserted in the wall. This was joined by a silk string to a gun sight–style instrument, with a pointed vertical element at the front and a peephole at the back. The artist aimed at the object and traced its outline on the glass, keeping the eyepiece aligned with the string to maintain the correct angle of vision.
The number of reflections, or bounces, a "ray" can make, and how it is affected each time it encounters a surface, is controlled by settings in the software. In this image, each ray was allowed to reflect up to 16 times. Multiple "reflections of reflections" can thus be seen in these spheres. (Image created with Cobalt.)
Ray casting
Videos
Ray casting is the methodological basis for 3D CAD/CAM solid modeling and image rendering. It is essentially the same as ray tracing for computer graphics where virtual light rays are "cast" or "trace
Ray tracing (graphics)
…algorithms for generating digital images. On a spectrum of computational cost and visual fidelity, ray tracing-based rendering techniques, such as ray casting, recursive ray tracing, distribution ray tracing, photon mapping and path tracing, are generally slower and higher fidelity than scanline rendering…
Ray-cast image of idealized universal joint with shadow
Camera models
Camera local coordinate system with the "screen" in the Z=0 plane
Example line drawings made by casting rays. Two are standard plan views. One shows hidden edges as dashed lines.