[Bf-committers] Cycles Progressive Refinement Checkbox Tooltip *somewhat* ambiguous

[Lukas Stockner]

This reminds me of https://developer.blender.org/D301, with a appropriate choice of samples taken per update. As far as I remember, it reduced the slowdown when using progressive from 30% to 6% for me.

Am 13.11.2014 10:58 schrieb Brecht Van Lommel <brechtvanlommel at pandora.be>:
>
> If it is really 100% or 300% slower then that sounds like a

fixable issue. > > I'm not sure why it would be this slow, it would be good to find out why, > but one thing that would speed it up is to render more samples at a the > time and redraw less often as the current sample increases. Due to the way > Monte Carlo integration works, one sample barely makes any visible > difference in noise after a while anyway. > > Maybe something like: > num_samples_at_once = sqrt(max(current_sample - 4, 1)) > On Nov 13, 2014 10:13 AM, "Greg Zaal" wrote: > > Just by the way, it's even more noticeable with GPU rendering - I've seen > it roughly 300% slower often. > > "could lead to significant slowdown" sounds good to me. > > On 13 November 2014 11:06, Sergey Sharybin wrote: > > > The issue here is that basically slowdown depends on particular hardware > > configuration, tile settings and device used to render (GPU/CPU). Meaning, > > on modern CPU i've noticed around 20% slowdown peak, which is not that bad > > as 100%. So what i'm trying to say here, is that if we'll provide > > information "up to 100% slower" it might just scary artists and they > > wouldn't use the option at all, even though for their configuration > > slowdown wouldn't be so bad. > > > > What about more neutral (in my opinion): "could lead to significant > > slowdown"? > > > > On Thu, Nov 13, 2014 at 12:22 AM, Simon Repp > > wrote: > > > > > Dear Renderistas, > > > > > > I only recently found out that progressive refinement in Cycles > > > rendering (which the corresponding checkbox's tooltip describes to be > > > "somewhat slower" than bucket rendering) in fact can impose performance > > > penalties of over 100% (aka the same amount of samples takes more than > > > twice as long to render). > > > > > > Now I don't know if this is just a personal flawed interpretation of the > > > english language on my part, but when reading "somewhat slower" I didn't > > > realize what I was really in for, and in retrospect I'd rather not > > > reconstruct how many days my poor laptop spent in excess to render some > > > projects I did in the past. > > > > > > I'd hereby like to propose a change of this tooltip to something less > > > ambiguous, lest anyone else falls into that same trap that I have - My > > > proposal for this would be to include actual figures describing the > > > possible speed penalty that progressive refinement can impose, that is, > > > something along the lines of "renders [a]% to [b]% slower depending on > > > the scene", where figures [a] and [b] are ideally derived from real > > > world data we gather (or already have?) about how much speed penalty > > > progressive refinement can impose in different scenes. Alternatively, > > > only stating "up to [x]% slower" would work as well I guess, as the main > > > point is to make people aware that it _can_ possibly affect render times > > > _significantly_. > > > > > > If the proposal to include figures is not agreeable for some reason, I > > > would at least ask for a more indicative wording than "somewhat slower", > > > which even after consulting multiple dictionaries I'm not sure if there > > > is an official interpretation for. (One dictionary suggests "quite" as a > > > synoym, another "slightly" ...) I'd still prefer the figures though, no > > > one looks up terms in the dictionary while using Blender and I am > > > probably not the worst offender at massacring and misunderstanding the > > > english language in the Blender community, and it doesn't get less > > > ambiguous than numbers anyway, so I say we use them here? :) > > > > > > Best, > > > Simon > > > _______________________________________________ > > > Bf-committers mailing list > > > Bf-committers at blender.org > > > http://lists.blender.org/mailman/listinfo/bf-committers > > > > > > > > > > > -- > > With best regards, Sergey Sharybin > > _______________________________________________ > > Bf-committers mailing list > > Bf-committers at blender.org > > http://lists.blender.org/mailman/listinfo/bf-committers > > > _______________________________________________ > Bf-committers mailing list > Bf-committers at blender.org > http://lists.blender.org/mailman/listinfo/bf-committers > _______________________________________________ > Bf-committers mailing list > Bf-committers at blender.org > http://lists.blender.org/mailman/listinfo/bf-committers