Search found 83 matches

by MohamedSakr
Fri Oct 03, 2014 11:33 pm
Forum: General Development
Topic: Questions about metroplis sampling.
Replies: 22
Views: 15432

Re: Questions about metroplis sampling.

sorry for jumping over the thread, but I wonder how ERPT works? my previous knowledge so far, how PT works, BDPT, VCM, PPM, PM + final gather, MLT (BDPT), MLT + MIS (MMLT) how ERPT is different? from the name it seems to apply only to PT, but can it apply to BDPT or VCM like algorithms? does it con...
by MohamedSakr
Fri Oct 03, 2014 5:42 pm
Forum: General Development
Topic: Questions about metroplis sampling.
Replies: 22
Views: 15432

Re: Questions about metroplis sampling.

sorry for jumping over the thread, but I wonder how ERPT works? my previous knowledge so far, how PT works, BDPT, VCM, PPM, PM + final gather, MLT (BDPT), MLT + MIS (MMLT) how ERPT is different? from the name it seems to apply only to PT, but can it apply to BDPT or VCM like algorithms? does it conv...
by MohamedSakr
Mon Sep 29, 2014 1:03 pm
Forum: General Development
Topic: Experimental Development Framework (C++ and ray tracing)
Replies: 12
Views: 10945

Re: Experimental Development Framework (C++ and ray tracing)

check Timo Aila framework :) , https://mediatech.aalto.fi/~timo/ , paper: Understanding the Efficiency of Ray Traversal on GPUs.

implementation: https://code.google.com/p/understanding ... l-on-gpus/
much simpler than Optix, more controllable, you can modify anything
by MohamedSakr
Mon Sep 29, 2014 1:00 pm
Forum: General Development
Topic: questions about displacement, normal and bump
Replies: 4
Views: 3931

Re: questions about displacement, normal and bump

If you are talking about physically accurate ray tracer then displacement mapping is the only way to go since both, bump and normal mapping, are not physically accurate at all, they are just a pretty looking fake. I totally understand this :D , I'm extending PBRT to use displacement mapping, just w...
by MohamedSakr
Sun Sep 28, 2014 4:43 pm
Forum: General Development
Topic: questions about displacement, normal and bump
Replies: 4
Views: 3931

questions about displacement, normal and bump

I understand in general the main difference between displacement, normal and bump. but what I need to know is "best practices with physically accurate ray tracer" so here are some questions: 1- I have an idea of implementing displacement into my render engine, it will be as simple as ( get low res g...
by MohamedSakr
Sat Sep 06, 2014 5:29 pm
Forum: General Development
Topic: rectilinear grids
Replies: 2
Views: 3494

Re: rectilinear grids

looks very cool :) , just 2 questions, which hardware you are using? (example GTX 780) , and what is the memory consumption for 10 million triangles?
by MohamedSakr
Sat Sep 06, 2014 1:36 pm
Forum: General Development
Topic: understanding sampling, filters, motion blur, DoF,...
Replies: 14
Views: 9386

Re: understanding sampling, filters, motion blur, DoF,...

a may be related topic, how to calculate the illumination taking distance into account "so I want to calculate the (Decay) for path (Throughput) depending on distance squared"

what I have is Throughput and Distance
newThroughput = f(OldThroughput, Distance);

what is the function?
by MohamedSakr
Sat Sep 06, 2014 1:31 pm
Forum: General Development
Topic: VCM GPU implementation (+ some extras)
Replies: 8
Views: 8394

Re: VCM GPU implementation (+ some extras)

NVM, I solved it :D , the problem was in my misunderstanding of PBRT image film, I was using film->AddSample(), while the correct is to use film->Splat() for rays which come from light and hits the camera lens, so the weighting should be fine now and results are correct
by MohamedSakr
Sat Sep 06, 2014 8:56 am
Forum: General Development
Topic: VCM GPU implementation (+ some extras)
Replies: 8
Views: 8394

Re: VCM GPU implementation (+ some extras)

I'm trying to implement VCM in PBRT, I have successfully done so far "vertex to vertex connection" , "camera vertex shadow ray" , "camera vertex hitting a light (BG or Area)" what I failed in is "light vertex hitting the camera lens" , it gives weird results!! and I tried all what I can do but someh...
by MohamedSakr
Fri Sep 05, 2014 1:19 pm
Forum: General Development
Topic: sampling pure specular paths
Replies: 4
Views: 4113

Re: sampling pure specular paths

ingenious wrote:You could probably also apply Kelemen-style mutations of the (x,y) position inside each pixel, in order to better explore the highlights inside it, instead of doing brute-force sampling.
yea I'm trying to avoid the brute force for this kind of problems :D