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Procedural planets : part IV

Posted: Thu Apr 21, 2016 9:24 am
by nevilclavain
Hi, Those last days, adding some shaders for Rayleigh[/url] and Mie atmospheric scattering. As do all those interested about this topic, I based my work on related awesome[/url] Sam O'Neil's work Adapt S.O'Neil shaders to my framework was not so easy; I got scared and I thought I would never make it, all this because of some stupid pitfalls I finally resolved, :victory: and now I'm happy with the result, even if the FPS took a hit once again :( Views from space : Views from surface:

RE: Procedural planets : part IV

Posted: Thu Apr 21, 2016 9:35 am
by XenonS
That's looking awesome :cool:I like the clouds especially.Planetside: roundish mountains are very old, young mountains should have sharp edges as stones on the ground, but I guess this goes at the limit of PC ressources... Greets,XenonS

RE: Procedural planets : part IV

Posted: Fri Apr 22, 2016 3:43 am
by nevilclavain
young mountains should have sharp edges as stones on the ground, but I guess this goes at the limit of PC ressources... Yeah I'd like to get more sharp edges, my mountains are a bit to smooth; I struggle to set fractal functions to do this. One possible solution should be ridged noise : http://www.decarpentier.nl/scape-procedural-basics[/url] Nev.

RE: Procedural planets : part IV

Posted: Fri Apr 22, 2016 3:52 am
by nevilclavain
Sky dome rendering from planet's surface is much better with simple HDR Formula : color_hdr = 1.0 - exp( -k * color ); with k = 0.91 for my personal case this avoids the huge white saturation stripe at horizon :good: What I cannot figure out is why S O'Neil wants the result of it to be stored in a separate float buffer, as it works fine directly implemented in the pixel shader :dontknow: ???

RE: Procedural planets : part IV

Posted: Fri Apr 22, 2016 9:09 am
by XenonS
50-60 FPS is very good, you are on a good way :haha:(But that's all I can comment, else I am a total noob in this area, I can only admire...) XenonS

RE: Procedural planets : part IV

Posted: Fri Apr 22, 2016 9:19 am
by fluffyfreak
Remember that a lot of the Seam O'Neil stuff was very early days of shaders. Including those GPU gems ones.So many decisions about where stuff could be stored was based on the limitations back then, a lot of those have no gone away and you can be much more flexible about it all. Also, nice work.

RE: Procedural planets : part IV

Posted: Sat Apr 23, 2016 1:12 pm
by sscadmin
Leaps and bounds over your last engine post, great work on tweaking the engine to get it to this point Nevil.

RE: Procedural planets : part IV

Posted: Sat Apr 23, 2016 3:15 pm
by nevilclavain
Leaps and bounds over your last engine post, great work on tweaking the engine to get it to this point Nevil. Thanks and yes this is funy to see this thing growing and progressing, even if significants issues and default remain Remember that a lot of the Seam O'Neil stuff was very early days of shaders. Including those GPU gems ones.So many decisions about where stuff could be stored was based on the limitations back then, a lot of those have no gone away and you can be much more flexible about it all.You're certainly right. Confused because I should have realize it by myself

RE: Procedural planets : part IV

Posted: Mon May 02, 2016 9:54 am
by nevilclavain
Randomized fbm and iq turbulence are nice, but I also need a way to control planet's topography and continent's shape. I therefore added some specialized code to do it; submitting the following bitmap, containing an example of continent map, to the new shaders : Black pixels (0,0,0) simply represents oceans and rivers; green channel is dedicated for plains and continents coasts altitude, and blue channel is reserved for areas where mountains are authorized; I get the following results: Vertex shader texture filtering activation is essential to avoid a "staircase" effect on the landscape, due to the huge size of the planet. 

RE: Procedural planets : part IV

Posted: Mon May 02, 2016 6:35 pm
by Geraldine
Only one word for this Nevil, beautiful, simply beautiful! :girlcrazy: