Path Tracing vs. Ray Tracing
&gt; Traditional ray tracing involves calculating the exact path of reflection or refraction of each ray, and tracing them all the way back to one or more light sources. With path tracing, multiple rays are generated for each pixel but they&#x27;re bounced off in a random direction. This gets repeated when a ray hits an object, and keeps on occurring until a light source is reached or a preset bounce limit is reached.<p>I&#x27;m not following completely. Are they saying that raytracing only generates new rays in the reflection or refraction direction? The diagram seems to contradict that, there&#x27;s three new rays generated at each surface for raytracing on that.<p>Does pathtracing not take reflection and refraction into account at all? Does it only generate new rays in random directions to sample the incoming light? The diagram shows two new rays being generated at each surface, and one of them fins a light each time.<p>&gt; But here&#x27;s the really clever part: ordinarily fewer rays would result in a less realistic lighting, but since the bulk of the color of the frame&#x27;s pixels are only affected by the primary rays, dumping most or all of the secondary ones doesn&#x27;t affect things as much as one might think.<p>I don&#x27;t understand this either. This just sounds like raytracing without reflections.<p>Can someone walk me through how the rendering of one pixel works in each case? I think the difference is how the secondary rays are generated, right?