High Dynamic Range (HDR) and Tone Mapping

In this second installment of the post processing series we learn the proper order of post processing effects as well as how games handle rgb values that exceed one, also known as high dynamic range (HDR).
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Music:
Joy - Persona 3 OST
During The Test - Persona 3 OST
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Thanks for watching!
This video is dedicated to my friend, Alotryx.
#acerola #gamedev #graphics #unity #unity3d #madewithunity #indiedev #unity2d #shader #hdr

[@gonderage]

i just found ya channel today, and you're criminally underexposed for the quality content you make. I never really knew anything bout tone mapping till now. Good channel :>

[@Acerola_t]

Thanks!

[@Cyberfishofant]

could the tumblin rushmeier tonemapper fix that?

[@myfavoritemusic2428]

you could say that his channel needs more exposure

[@roxiethorne]

Another certified Acerola classic

[@microdavid7098]

there's a lot of good info in this channel. One of the few gamedev channels that really dives into technical stuff

[@DavidAddis]

What a fantastic video! I had wondered how the maths of HDR rendering worked for so long, and you explained it clearly and quickly.

[@bitbraindev]

These videos are so interesting to watch! You earned my subscription.

[@nibblrrr7124]

I'm still undecided as to whether _Tumblin Rushmeier_ sounds more like a daredevil aerobatics maneuver, a stiff drink, or the stage name of some crusty country-blues guitarist.

[@corok12]

I found your channel last week, and your sub count has been shooting up every time I've come back. Keep it up! Excellent videos!

[@Acerola_t]

Thanks! My videos seem to have finally found the right audience lol

[@BobzBlue]

I always set the minecraft seus shader to aces just because I thought it looked better, I didn't know it was actually objectively the best

[@Acerola_t]

there isnt really an objectively best tone mapper it's very context dependent lol aces is just the default 'looks good' tone mapper

[@BobzBlue]

I was going to say industry standard but I was too tired to remember if that was the term you used.

[@oby1]

Bruh. Your videos are extremely high quality. I binge watched em all ^-^

[@khalidnaqeeb6512]

Thanks for letting me know about my tcl tv Using this technology you talked about 🙏🏻❤

[@GameDevGeeks]

very clear explanation! amazing content

[@FirstKeeper]

Great video, thank you!

[@controlflow89]

Subbed! Great content 🙏🙏🙏

[@kevinchen8325]

this channel is so underrated this is so good!

[@tnt345i7]

cool video, maybe you should cover a pixelation effect, like in "dead cells" and a "a short hike" or stuff that t3ssel8r makes. pixel art sprite rotation (like in noita or guns in ETG)

[@Acerola_t]

That's a great idea! I'll add that to the list of video plans.

[@avivkandabi7088]

@@Acerola_t Looking forward to it :D

[@AyushBakshi]

Great channel you built there! Short and dense 👌🏻

[@myfavoritemusic2428]

it's astonishing how motivated and de-motivated you sound at the same time (this is a compliment, or it is intended at that)

[@simply_aman]

omg bro u r soo underrated that i am first time sharing someone on my whatsapp status! Good work man

[@mskiptr]

Cool video hartoundebreado! Btw, Narkowicz (in Polish) would be read like nar-ko-veech _w->v; i->ee; cz->ch_ (and the full name is Krzysztof Narkowicz -> kshish-tof nar-ko-veech)

[@Acerola_t]

This is very helpful, thank you!

[@kkibi]

nice!

[@NumberOneRandomz]

killin it

[@blacklistnr1]

@1:57 Quite niche nitpick: the purple you show there is a cool color as most of its variants are due to its blue component, although is does tend to look quite warm when it gets into the pinks.

[@bfmwaves558]

I have a question about the Tumblin Rushmeier tonemap, I'm looking for an example of GLSL code, but I can't find any. I'm looking to implement it in a shader for minecraft with plain other tonemaps like Reinhard, Uchimura or ACES, which I already have. Could you help me with this? By the way, your video is awesome ! I'm using a translator, so sorry if it's not right..

[@Pauglin]

thanks

[@Rumplestiltzchen]

This music is groovy!

[@Saturn2888]

This would've been better if it lead into how SpecialK and Windows/Xbox Auto HDR work. I think the video unlocked that reasoning for me, but didn't go into enough detail with it. Either way, it was clear why SDR games looks so bad once you put those all on the screen (except Tumblin Rushmeier). There's simply not enough dynamic range available, so everything looks like it has a haze over it. Did Valve's HL2 HDR use something similar? From what I can tell, the reason Tumblin Rushmeier looks better is because it allows clipping at the top range; something HL2's HDR had as well.

[@Acerola_t]

I'm gonna explain auto exposure in my next vid, don't worry!

[@Saturn2888]

@@Acerola_t Awesome! What a great channel! Could do without the pink-boxed video, but the rest is fantastic! I enjoy watching your newer video more than your old ones. For some reason, the Minecraft shader video wasn't as fun to watch; still good content, but didn't grab me the same as the newer ones.

[@Acerola_t]

@@Saturn2888 Yeah I've learned a lot since the minecraft video lol Thanks for watching!

[@TheMrLeoniasty]

Nice video ! I work in VFX and not games so It may work different there, but shouldn't exposure go before bloom? So that the threshold is proper for the image? At least thats how I usually add it in my workflow.

[@Acerola_t]

Technically yes exposure should go before bloom but it's simpler to have exposure as part of the color correction pass, in an ideal world you have exposure as a parameter of the bloom pass too.

[@TheMrLeoniasty]

@@Acerola_t yeah, makes sense. It's the same problem I always have when applying motion blur and lens blur. The physically accurate way it so apply them at the same time, like in a camera (or just a plain pathtrace render engine), but in software like After Effects one has to be before the other. I usually go with motion blur first and then lens blur. I know Nuke has a way to implement them both accuratelly at the same time.

[@radicant7283]

Acerola I love you~

[@Jaspev]

Nice hoodie

[@ViRiXDreamcore]

I’d mlove to get more info on HDR, for monitors that support it

[@inconnn]

would anything interesting happen if you applied a different curve for red green and blue? i'm sure it would look weird but seems kinda interesting

[@Acerola_t]

That's an interesting idea, I will try it out sometime lol

[@mikafoxx2717]

Funny that the oldest was more preferrable. I think it's because it leverages a more HDR look. On modern monitors you dont need to squash it down as much because we have such a high brightness ceilling. If only HDR was better standardized.. nobody runs their displays at 100 nits peak brightness these days unless you're some kind of editor

[@RemjieGemillion]

in fact, Unreal Engine seems to use their own color correction curve, a simpler one who gave similar result than ACES. I tryed it on Unity, it gave nice results.

[@inodedentry8887]

Do you know about Tony McMapface? It's a perfectly cromulent tonemapping algorithm! I'd even say one of the best!

[@xGOKOPx]

How does this relate to working with HDR displays? Do you just skip tonemapping? What about gamma correction? Asking theoretically because I don't even have a HDR display haha

[@Acerola_t]

That tech is so new that I'm not sure if there's really an industry standard approach, but I think you skip tonemapping yeah gamma correction goes after tone mapping because you don't want to apply an exponent to a term that is outside the range 0-1, I am unsure how you would apply gamma correction in an hdr display context or if you would even need to.

[@Antsaboy94]

How about you maintain the ratios between RGB values and apply tone mapping on their luminosity value?

[@anonymouscommentator]

this seems like a fairly easy effect to implement. why do e.g. windows or youtube struggle with it so much? in linux it has already take quite some time and we are just now on the steam deck beginning to see some hdr implementations. what am i missing?

[@anonymouseovermouse1960]

Honestly, the likeliest reason is that windows and YT don't give enough of a fuck to work on a solution

[@Maleriandro]

1:27 But in the last video you said that you lied to us because bloom comes after gamma correction #AcerolaLiedPeopleDied, but now its the gamma that is the last. sooo you technically didn't lie? #AcerolaDidntLiePeopleDidntDie

[@chickennugget6684]

so that's why certain games on Ps4 make the colours on the home screen go wack and look unsaturated (atleast on our projector) cool stuff.

[@sehzadeselim863]

4:55 I supposed he had suggested using L(x, y) / (1 + L(x, y) ) + 0.5 instead xd

[@alejandrocambraherrera8242]

You said bloom comes after colour correction in your Elden Ring video 🤔

[@Acerola_t]

I lied :)

[@gscruz7840]

Hey I have a question. Do you recommend going to college to learn: Coding/ Game dev?

[@Acerola_t]

It really depends, I personally do really well in formal education environments and I prospered a lot in school. If it wasn't for my first few college classes I wouldn't be interested in graphics or be making these youtube videos at all. One thing I really had to learn and struggled with was self motivation and teaching myself skills, which is incredibly valuable and necessary if you want to succeed in these fields. Game development especially, a portfolio is necessary to get a job anywhere and school isn't going to help you with that very much. If you are going to university and are choosing between computer science/game dev, you should do computer science since it's a much more valuable degree and opens you up to way more jobs than game dev specifically, I know many people who went for game dev and learned that they hate working in the industry and are now stuck. School is not a necessity though, there's many people who teach themselves how to program, make programs to demonstrate those skills, and show them to employers and get hired. What school does is it provides you with a formal structure to learn, as well as giving you tons of connections which are invaluable. I wouldn't be working at Intel if I didn't make a connection during my time at university.

[@gscruz7840]

Dang. Thanks for the response. I will look into the computer science thing see if I develop and interest for it

[@mrnipzs7604]

@@gscruz7840 update?

[@onceagain569]

@@Acerola_t Just wanted to say I really appreciate your response :)

[@az-kalaak6215]

I have a question which could be a suggestion too regarding everything I saw today from your channel (mainly grass), could you please explain hos some games do to do fire-propagation on grass ? is is post-processing part ? does it mean grass needs representation on cpu side ?

[@Acerola_t]

Honestly I'm not sure how it works, yeah it needs some representation cpu side but I'm not sure how games like breath of the wild do it.

[@az-kalaak6215]

@@Acerola_t from what I would implement it, i would do smaller chunk that can get three states "normal" "on fire" "burned" cpu side, only the chunk exists, however gpu side chunk have grass inside the fire spread would be calculated cpu side and the graphical effect gpu side however, since i'm not a graphical dev nor a shader dev, I have no clue if this is even possible (and i'm not even talking about optimisation as well.... you cannot really optimise something you don't know how to do haha) inside a chunk if seeking more realism it would probably be possible to give the starting position of the fire (gpu side) to adapt the graphical effect, syncing it to th cpu calculation to spread it. would be squar-ish but maybe hexagonal shaped chunk would do it ? sub-chunking might get too much ressources so that's the only part i can see and in botw from what I remember the grass is not really burned, it is bent to the ground with a black texture and burning always is a small circle (when it does not propagate) I know far cry serie also have propagating fire, I could try to contact a friend that worked at ubisoft to see if he know how they did this (dunno if he'd respond though)

[@nathanhelmburger]

Or... You could use the Power of AI!!! kzbin.info/www/bejne/d3imeWR9h5yjhrc

[@abulak3477]

in unreal they already built-in

[@Acerola_t]

It's also built-in for URP and HDRP in Unity as far as I know, but the point of my videos is to understand how those built-in features work under the hood.

[@Marc142000]

Oh so bloom doesn't come last?

[@Acerola_t]

no any hdr effects come before tone mapping

[@Marc142000]

Thank you for the reply in this older video!! Keep doing amazing stuff

[@mattsmith4684]

You're pretty cute

[@thegirlwithmemes]

egg lol

[@NielsGx]

Hable is too dim and grey compared to reinhard sadly MPV video player has no other tone mapping available

[@gustavbw]

So, temperature is Saturation, tint is Hue and exposure is Value? (Speaking in HSV terms that is)

[@gustavbw]

@@gregoryford2532 no

[@felixmoore6781]

No. Those are 3 quantities that define an element in the HSV color space, a color. Temperature+tint and exposure are operations or transformations on color space elements. But you can have a saturation factor, which is still not even close color temperature, a hue shift, which is not as far off but still not even close to tint, and a value factor, which actually can behave kind of like exposure, but the calculations are probably different. And exposure is often quantified in "stops", so the factor there changes exponentially.

[@id462408]

ssr

[@Saturn2888]

Super side comment: Do you live in a trailer home or RV? Your room layout seems very awkward for a house. The window is super low and long, there are cabinets sitting over a couch, and the ceiling shrinks by a foot over that cabinet.

[@Acerola_t]

I record in an rv