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Is this path tracing or ray tracing? both seem to be mentioned. The examples look too physically accurate for ray tracing but I know it's often incorrectly used
by tomxor 8y ago
Is this path tracing or ray tracing? both seem to be mentioned. The examples look too physically accurate for ray tracing but I know it's often incorrectly used as a synonym for a superset of path tracing (which it's not).
- petermcneeley 8y agoThese terms tend to be used interchangeably. In the context of your original quote I think path tracing is the more accurate term. Even Arnold Renderer is described as a raytracer. ( https://en.wikipedia.org/wiki/Arnold_(software) https://en.wikipedia.org/wiki/Arnold_(software) ) https://news.ycombinator.com/item?id=17126961 https://news.ycombinator.com/item?id=17126961
- tntn 8y agoMost resources I've seen refer to the whole class of methods that involve tracing rays as "raytracing," and use "path tracing" to refer to the special case of raytracing with a Monte Carlo integrator. I'm not sure why you are so adamant that it is incorrect; it's fairly common to refer to more than just ray tracing with a Whitted integrator with the term.
- modeless 8y agoIt is not incorrect to use "ray tracing" as a generic term. Path tracing is a kind of ray tracing. The actual process accelerated by the hardware is finding the intersection of a ray with a set of triangles, which can be used for any kind of ray tracing including path tracing.
- tomxor 8y agoI disagree, it's quite a different algorithm, the main difference being ray tracing traces a path to each light in the scene at each intersection which requires far less steps to produce a visually pleasing image but is physically inaccurate, whereas path tracing takes no shortcuts, it traces a new ray at each intersection based only on the BRDF function until it either reaches the recursion limit or hits a light source, this is why it's so accurate but slow... It's not an extension of the ray tracing algorithm. But as others point out I suppose this hardware works at a lower level than either of these algorithms by essentially just accelerating ray intersections.
- modeless 8y agoYou are mistaken about the term "ray tracing". It is a generic term. The specific algorithm you describe is "Whitted ray tracing", a particular type of ray tracing.
- tomxor 8y agoThat's what most people mean when they say ray tracing... but who says ray tracing path tracing... no one. There's plenty of articles comparing the two and they almost always refer to the former as just "ray tracing".
- deleted 8y ago[deleted]