Precise Embree option

[FrostKiwi]

Any reason why you would check these (on by default), I see no difference on multiple tests, including animation.
Why not have free 70k ray/s / faster render?

[Ludvik Koutny]

Any reason you would mess with debug settings?

[FrostKiwi]

Any reason you would mess with debug settings?

Free powa :D
No, just curious to know, when the precision is needed.

[Ondra]

render interior lit by enviro light with high-poly one-sided geometry curtains in windows and you will see ;

it helps with this kind of small light leaks. 70k rays/s will save you few minutes... but if you ever run into this problem, you will lose hours. So it is on as an insurance ;)

I would put it in more prominent tab and announce its meaning, but then the internet would be full of "100% universal settings" guides telling people to turn it off as a first thing in new scene. And then there would be bug reports from clue-less people about light leaks ;)

[FrostKiwi]

render interior lit by enviro light with high-poly one-sided geometry curtains in windows and you will see ;

Ye, found light leak in translucent materials, this is fixed by the precise flag.
I'm still curious though what "high quality" means. If it's no trouble I'd love to know...

[Ondra]

it enables the "precise" flag in embree. That causes embree to use slower ray-triangle intersection algorithm, that is watertight (does not let any rays through on boundaries).

I think you mentioned you study IT, so you probably know about problems with float imprecision. The fastest ray-triangle intersection method (moller-trumbore) suffers from some catastrophic cancellations in some cases - it calculates the volume of tetrahedrons created from ray origin, intersection point, and 2 points of the triangle. This volume is zero on edges, because all 4 points lie in single plane. This zero will easily ruin your day, because you need to invert it.

[FrostKiwi]

it calculates the volume of tetrahedrons created from ray origin, intersection point, and 2 points of the triangle. This volume is zero on edges, because all 4 points lie in single plane. This zero will easily ruin your day, because you need to invert it.

thx^^
ye, I study computer-science