Search found 47 matches

by koiava
Thu Dec 04, 2014 6:47 am
Forum: General Development
Topic: Colibri Renderer
Replies: 12
Views: 11100

Re: Colibri Renderer

Pretty cool! Thanks! :) And that is just one year of development? Yes, maybe little bit more, but I'm working in full time job and unfortunately it's very hard to find enough free time for Graphics. So, I decided to do it more serious, because when I do computer graphics I feel really good :) Do yo...
by koiava
Wed Dec 03, 2014 7:30 am
Forum: General Development
Topic: Colibri Renderer
Replies: 12
Views: 11100

Re: Colibri Renderer

YxmqBywMtR4 Here I show progressive rendering in my path tracer. Performance shown here is really bad :D I know. This is old version actually, after that I added packet tracing for primary rays it helps a lot in this type of scene. I improved traversal code significantly and speed is much better no...
by koiava
Sat Nov 29, 2014 6:32 pm
Forum: Visuals, Tools, Demos & Sources
Topic: Direct Light Integration using MIS
Replies: 11
Views: 14038

Re: Direct Light Integration using MIS

This is precisely what I'll use to demonstrate MIS the next semester. Great stuff indeed, thanks!
Yeah, I showed this to my students and I think It is more clear to understand concept and basic idea of method, when you have small, lightweight, easy, real-time demo with full source code.
:)
by koiava
Sat Nov 29, 2014 4:12 pm
Forum: Visuals, Tools, Demos & Sources
Topic: Direct Light Integration using MIS
Replies: 11
Views: 14038

Re: Direct Light Integration using MIS

thanks guys! :) :) :)
Yeah, shadertoy is really good place to do some small experiments and share with community.
I will find more time to make code more small, readable and easy to understand.
by koiava
Fri Nov 28, 2014 8:19 am
Forum: General Development
Topic: How to sample angular environmental map?
Replies: 3
Views: 3851

Re: How to sample angular environmental map?

as I guess you need something like this: color envMap::GetColor( vec3 dir ); So, there is really simple math. assumption is that those images is taken from infinite distance and viewing rays are parallel, for example (0.0, 0.0, 1.0) color envMap::GetColor( vec3 R ) { const vec3 E( 0.0, 0.0, -1.0 ); ...
by koiava
Thu Nov 27, 2014 9:21 am
Forum: Visuals, Tools, Demos & Sources
Topic: Direct Light Integration using MIS
Replies: 11
Views: 14038

Direct Light Integration using MIS

https://lh5.googleusercontent.com/-MUxHJB4qTHQ/VHbsSSkdVYI/AAAAAAAAGjo/B14pxwFrmA0/w640-h360-no/MIS.png For all time I couldn't fully understand how MIS actually works and finally I found enough time to think about MIS more deeply to make things totally clear. So, from my opinion, things always is ...
by koiava
Fri Sep 26, 2014 6:48 am
Forum: General Development
Topic: avoid rejection sampling
Replies: 6
Views: 5470

Re: avoid rejection sampling

according to SolidAngle documentation, Arnold has shadow_terminator_fix option, but this solution doesn't work in some cases. It works great for convex meshes, but may produce artifacts in concave areas of high curvature. A proper solution in this situation to reduce the shadow terminator artifact i...
by koiava
Thu Sep 25, 2014 8:30 am
Forum: General Development
Topic: avoid rejection sampling
Replies: 6
Views: 5470

Re: avoid rejection sampling

Energy Conservation is another problem here. When I evaluate BRDF, if it always gives me a ray from hemisphere(directed to perturbed normal) minus solid angle(which fall under surface), then a corresponding pdf isn't normalized anymore and correct normalization isn't easy task for complicated BRDFs....
by koiava
Wed Sep 24, 2014 8:09 am
Forum: General Development
Topic: avoid rejection sampling
Replies: 6
Views: 5470

Re: avoid rejection sampling

https://lh6.googleusercontent.com/-qhk1pZRayRM/VCJ7HMeUm6I/AAAAAAAAGdQ/kIgCOuWDbmk/w464-h248-no/perturbed_normal_problem.png this is a figure illustrating this problem. If surface is highly specular then probability that reflected ray will fall under the surface is high. Actually, this is a reason ...
by koiava
Wed Sep 24, 2014 7:04 am
Forum: General Development
Topic: Boosting Monte Carlo Rendering by Ray Histogram Fusion
Replies: 8
Views: 6934

Re: Boosting Monte Carlo Rendering by Ray Histogram Fusion

Unless I'm misreading it, the paper cites filtering times ranging from 5 to 115 seconds, which seems rather large for real-time applications. yeah, maybe I exaggerated things little bit, but the Idea is really simple to classify pixels using histogram. I think this Idea can be extended to use diffe...