Sugárkövetés

Sugárkövetés, or ray tracing in English, is a rendering technique used to generate an image by tracing the path of light rays through a virtual scene. Unlike traditional rasterization methods, which project 3D objects onto a 2D screen, ray tracing simulates how light interacts with surfaces in a more physically accurate way.

The process begins by casting rays from the virtual camera, or viewpoint, into the scene. When a ray intersects an object, its behavior is determined by the surface properties of that object. For example, a ray might be reflected, refracted (bent) as it passes through transparent materials, or absorbed. For each ray, the algorithm calculates its color based on the light sources it encounters and the interactions it undergoes. This process is repeated for millions of rays to construct the final image.

The primary advantage of ray tracing is its ability to produce photorealistic visuals. It naturally handles complex lighting effects such as realistic reflections, accurate shadows, refractions through glass or water, and global illumination, where light bounces indirectly off surfaces to illuminate other parts of the scene. This realism comes at a computational cost, as tracing each ray and its subsequent interactions can be very intensive.

Initially confined to offline rendering for films and architectural visualizations due to its demanding nature, ray tracing has seen increasing adoption in real-time applications like video games with the advent of specialized hardware. Graphics cards now often include dedicated ray tracing cores, significantly accelerating the process and enabling real-time ray-traced graphics.