Introduction of some graphics concepts, personal excerpts or sorting, as the entry quotes of personal articles;
Rendering Equation (Rendering Equation) :
In computer graphics, the rendering equation is an integral equation, which is the theoretical basis of all global illumination methods (ray tracing, path tracing, radiance, etc.); it describes the flow of light energy in the scene and is not perceptible in rendering The most abstract formal expression of the aspect; according to the physics of optics, the rendering equation theoretically gives a perfect result, and various rendering techniques are only an approximation of this ideal result;
In 1986, James Kajiya introduced it into computer graphics; in computer graphics, the goal of photorealistic rendering is to solve this equation; the physical basis of the rendering equation is the law of conservation of energy; at a specific position and direction, the emitted light Lo is The sum of the self-luminous Le and the reflected light, the reflected light itself is the sum of the incident light Li in all directions multiplied by the surface reflectivity and incident angle;
This equation connects the outgoing light and the incident light through the intersection, and it represents all the light transmission in the scene; all more perfect algorithms can be regarded as the solution of this equation in a special form;