fénykövetést

Fénykövetés, in English known as ray tracing, is a rendering technique for generating an image by tracing the path of light in a scene. It simulates the physical behavior of light, allowing for highly realistic visual effects. Unlike rasterization, which projects 3D objects onto a 2D screen, ray tracing follows individual rays of light from the viewer's eye backward into the scene.

When a ray encounters an object, its behavior is determined by the object's material properties. The ray can be reflected, refracted, or absorbed. For reflections, a new ray is cast in the reflected direction. For refraction, a ray passes through a transparent object and changes direction. Absorption means the ray is stopped. These interactions are calculated recursively, meaning that reflected and refracted rays can themselves bounce off other objects, creating complex light paths.

This recursive tracing of light rays allows for the accurate simulation of phenomena such as global illumination, soft shadows, reflections on curved surfaces, and the way light scatters through translucent materials. These effects are difficult or impossible to achieve with simpler rendering methods, making ray tracing a powerful tool for creating photorealistic computer-generated imagery.

While computationally intensive, advancements in hardware, particularly with dedicated ray tracing cores in modern GPUs, have made real-time ray tracing increasingly feasible in video games and other interactive applications. It is also widely used in film production for visual effects and animation, as well as in architectural visualization and product design. The pursuit of more efficient and sophisticated ray tracing algorithms continues to be an active area of research in computer graphics.