Sädejäljitys

Sädejäljitys, commonly known as ray tracing, is a rendering technique used to simulate the physical behavior of light. It works by tracing the path of light rays as they travel from a virtual camera through a scene, interacting with objects and surfaces. When a ray encounters an object, its behavior is determined by the material properties of that object. This can involve reflection, refraction, and absorption.

The process is computationally intensive because it requires calculating the interactions of a vast number of rays for each pixel on the screen. Unlike traditional rasterization techniques that project 3D objects onto a 2D plane, sädejäljitys aims for a more physically accurate representation of how light behaves in the real world. This leads to more realistic lighting, shadows, reflections, and refractions.

The visual fidelity achieved through sädejäljitys can be significantly higher. Shadows are softer and more accurate, reflections are sharp and detailed, and the way light bounces and scatters creates a sense of depth and realism. This makes it a powerful tool in computer graphics for applications like film visual effects, architectural visualization, and increasingly, in video games.

While historically limited by performance, advancements in hardware, particularly with the introduction of dedicated ray tracing cores in GPUs, have made real-time sädejäljitys feasible for interactive applications. This has opened up new possibilities for creating immersive and visually stunning digital environments.