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picogen 0.3 - volumetrics-pfx



Software: To learn more about picogen, the free software used to create this image, visit #picogen or [link] .

About the image: It is the same image as [link] , but which is without post-fx applied. The following three paragraphs are a copy of that deviation (enclosed in ++--).

About the image, programming-wise: This week I implemented volumetric rendering in picogen, largely influenced by PBRT (actually, one could call the renderer to be of the "PBRT kind" :) ). After 3 days of spare time hacking (yay, that is not even a normal working day:D) I got this result.

About the image, image-wise: This is not a lens flare effect. Lense flare effects occur due to very bright light bouncing inside your camera's lens construction ([link]). What you see in this image are so called "crepuscular rays", sometimes called "god rays".

Shadow is the absence of light, so the dark regions are really volumetric shadows thrown by the mountains, into the dense atmosphere. Those light shafts are actually (near-) parallel (*), and it is the position of the observer and the wide distance of view that make them look like emerging from a common center. I still think this is a fascinating effect, even, or better, especially, after "implementing" them. More about that phenomenom: [link] .

(*) While god rays are indeed only near-parallel in nature (but that "near" is not obvservable by us), they are really parallel in picogen, as they are implemented in terms of a directional light source, which is programmerish for an optimized light that has no position, which is a very good approximation for sun light

Why this post-fx version? Because I was surprised what a simple post-effect like unsharp-masking, a technique to increase perceived sharpness of an image, in use by photographs since the 30s, can do about the image.

Decide for yourself which one you like, for my part, I seriously think about making this post-effect an optional part of picogen.


Sidenote for DigitalLandscapes and everyone else: Please grill and fry me, I am programming this thing, so I might loose my sense for aesthetics from time to time.
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dpow3r's avatar
Without a doubt,your raytraced terrains are the most beautiful ones that i've seen so far in the internet.
I hope one day i'll have the time and courage to do something similar to your work =).