Algorithms
The twilight ray tracer is based on these algorithms.
Standard ray tracer
The Standard Raytracer option produces rather unnatural-looking images, as this algorithm ignores indirect lighting for diffuse materials and always calculates ideal reflections for reflective materials. However, the calculation with this option is quite fast.
Path tracer
PT is a ray tracing method, with the help of which a global illumination simulation can be carried out. Rendering with the Pathtracer option is qualitatively better compared to the standard ray tracer.
Photon mapping
The aim of photon mapping is to determine the global global illumination of a scene efficiently and thus to create realistic images in less time. It can be divided into two phases. In the first phase, photons are sent into the scene from a light source. With every interaction with a diffuse surface, an entry is stored in a photon map. This map is then used to calculate the illumination of the scene.
Bidirecitonal path tracer
BTP is a path tracing process in which ray paths are generated by the camera as well as by all light sources in the scene and are linked together.
Radiosity
The radiosity algorithm was developed in 1984 by Goral, Torrance, Greenberg and Battaile. It is a global illumination method that is ideal for diffuse reflecting surfaces. This corresponds well to reality, since diffuse reflections are often encountered in practice, whereas completely reflective surfaces tend to be the exception.
Metropolis light transport
MLT is a path tracing process in which randomly distributed initial paths on the image surface are mutated according to special rules until all image pixels are covered and the desired accuracy and mutation rate are achieved.