Title: Help with SunSky Post by: Patryk Kizny on November 20, 2015, 10:39:46 PM Hey,
There's SunSky in frag examples that I am using with my renderer now. The problem I encountered is that the bottom hemisphere is grey and I wanted to make it black or adjustable. And I can't seem to be able to find what to modify to tweak it. Any help? Title: Re: Help with SunSky Post by: Syntopia on November 21, 2015, 01:09:37 AM In 'vec3 sunsky(vec3 viewDir)' you can insert a line before the 'return' statement like:
Code: sky = dot(up, viewDir)<0.0 ? 100.0*vec3(1,0,0) : sky; You still get a bit of grey near the horizon - here you can cheat a little and pull the sky down, by changing to: Code: float cosUpViewAngle = dot(up, viewDir); If you want the to use the fake ground color to actually light your model, you'll have to update the 'sky' method as well. Title: Re: Help with SunSky Post by: Patryk Kizny on November 21, 2015, 01:28:44 AM Thanks. That cuts a straight line which is not too cool.
I was rather curious what causes the effective grey in the lower hemisphere and how to create an organic falloff to black instead of grey. Title: Re: Help with SunSky Post by: Syntopia on November 21, 2015, 04:59:44 PM You ¨could mix in something smoothly based on the "dot(up, viewDir)" which is 1 for up, 0 for the horizon, and -1 for down.
I think all atmospheric models will turn white/grey near the horizon. The models are not welldefined below the horizon. Title: Re: Help with SunSky Post by: Patryk Kizny on November 21, 2015, 05:56:18 PM Thanks. That's what I did. What was better as a tweak in fact was to rotate the sky view dir along the Right axis. That way I achieve camera-dependent horizon shift which lowers the horizon to compensate for missing content due to limited raytracer range. Thanks a lot for your help! |