HDR + Tonemapping + Skylight = Fail?

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52 comments, last by riuthamus 11 years, 7 months ago
So, we got some free time and wanted to add in some sexy lighting to our system. ( we already had lighting but without the HDR and Tonemapping ). We took a look at how MJP suggested to do it and implemented it in a way that matched his for the most part. After doing so we noticed our entire world got really dark! Some of you might not know what these two things are:

HDR: ( fastest description for easy understanding )

Basically makes your images high contrast showing a wider range of color and depth.

TONEMAPPING:

Takes HDR and turns it back to LDR for displaying on monitors and for print preparation, since most monitors do not display images in HDR contrast ratios.

So... in theory this is why our entire world started to get dark. The problem is we dont know what settings to modify or mess with in order to fix our issue related to darker than normal looks. We could, and have, amped up the lighting values to some crazy number and while that did fix some of the issues it did not fix our sky.

This brings us to the new problem, how do we get the HDR and Tonemapping to properly apply to the sky? BTW, this was all spawned from trying to create caves and lighting in them! DAMN YOU CAVES!!
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What kind of tonemapper are you using? Are you using a decent adaptive exposure system?
HDR isn't just some plug-and-play technique, you need to design your lighting pipeline around it to make it work properly.

I gets all your texture budgets!

Hi,

Probably your sky texture is a low-dynamic-range texture ranging from 0.0 - 1.0 and your HDR values are some magnitude bigger. So, you may multiply your sky color by some value which makes it look nice. Also, you may make your sky texture a HDR texture too, and using some clever encoding it may not take more space than a regular texture.

Cheers!

What kind of tonemapper are you using? Are you using a decent adaptive exposure system?
HDR isn't just some plug-and-play technique, you need to design your lighting pipeline around it to make it work properly.


Indeed, we noticed this shortly after adding it to the project! It changes all my settings when I enable the HDR since sun and sky and even ground lighting has to be modified to correct for it. We are using the system that MJP suggested for tonemapping, although our knowledge on the subject is limited compared to his we figured it would be best to try and mimic it. I think the name is called Reinhart? We do have auto exposure system... although as to how well it is working cant really be decided at this point since everything is just ultra dark!


Hi,

Probably your sky texture is a low-dynamic-range texture ranging from 0.0 - 1.0 and your HDR values are some magnitude bigger. So, you may multiply your sky color by some value which makes it look nice. Also, you may make your sky texture a HDR texture too, and using some clever encoding it may not take more space than a regular texture.

Cheers!


Well, you are correct to some degree, although we do not have a sky texture. We are using code to create the colors, but we are noticing the same thing... the sky light in hdr is like 12 but with the tone mapping applies we are getting .42 or something... obviously very different numbers.

and to better understand I have attached some pictures!

BEFORE TONEMAPPING and AUTO EXPOSURE ( So just HDR ):
gallery_1_168_46374.jpg

AFTER TONEMAPPING AND AUTO EXPOSURE:
gallery_1_168_53750.jpg
I'd recommend you try out some different tone mapping algorithms (definitely look at some filmic tone mappers) and to adapt your lighting to work properly in a HDR environment.
Have a look at John Hable's site, he has some very decent articles about tonemapping and HDR-related techniques which go into quite some detail.

I gets all your texture budgets!


I'd recommend you try out some different tone mapping algorithms (definitely look at some filmic tone mappers) and to adapt your lighting to work properly in a HDR environment.
Have a look at John Hable's site, he has some very decent articles about tonemapping and HDR-related techniques which go into quite some detail.


You are a wealth of information sir! thank you
My pleasure smile.png

I gets all your texture budgets!


My pleasure smile.png


saw your project, looks really good! Good luck with the engine!

[quote name='Radikalizm' timestamp='1345935064' post='4973357']
My pleasure smile.png


saw your project, looks really good! Good luck with the engine!
[/quote]

This is quite off-topic, but our site is horribly outdated I'm afraid.
There have been some major improvements to our technology (the screenshots on the site show mostly old techniques) and our main focus is actually our game of which we've shown absolutely nothing yet

I gets all your texture budgets!


[quote name='riuthamus' timestamp='1345937053' post='4973362']
[quote name='Radikalizm' timestamp='1345935064' post='4973357']
My pleasure smile.png


saw your project, looks really good! Good luck with the engine!
[/quote]

This is quite off-topic, but our site is horribly outdated I'm afraid.
There have been some major improvements to our technology (the screenshots on the site show mostly old techniques) and our main focus is actually our game of which we've shown absolutely nothing yet
[/quote]

Indeed, off topic, but i saw your engine and saw some of the screenshots you had and thought "This guy might actually know what he is talking about" since you already seem to have some of the effects/lighting being described here. Anyway, back to ON TOPIC! :P

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