Search found 89 matches

Fri Nov 08, 2013 7:40 pm
Forum: General Development
Topic: newbie (about intersection tests and drawing pixels )
Replies: 5
Views: 5508

Re: newbie (about intersection tests and drawing pixels )

By quad i think something like parallelogram - think the cost of testing it should be about the same as 1 triangle not 2 triangles. If you have a triangle intersection test that computes u/v coordinates (e.g., for normal interpolation or texture coordinates) then it's pretty trivial to modify for p...
Thu Nov 07, 2013 5:33 pm
Forum: General Development
Topic: raytracing bezier patches..
Replies: 5
Views: 6634

Re: raytracing bezier patches..

It's typically defined as a set of bicubic Bezier patches, which is about as simple as general-use parametric patches get. The easiest way to deal with them is to tessellate the patches into triangles and render those. Alternatively you could try tracing the patches directly. There are a few ways to...
Thu Nov 07, 2013 2:32 pm
Forum: General Development
Topic: newbie (about intersection tests and drawing pixels )
Replies: 5
Views: 5508

Re: newbie (about intersection tests and drawing pixels )

but something long and weird (and bad) for Ray Quad intersection - need to found some better intersection routines for this and for other 'figures' it too could be useful. Could someone help with that ? some good routines ? much tnx Define 'quad'. Do you mean a rectangle? A planar quadrilateral? A ...
Fri Sep 27, 2013 4:13 pm
Forum: General Development
Topic: Path Tracing problem with indirect light
Replies: 7
Views: 5381

Re: Path Tracing problem with indirect light

Really thank you! That was a painful mistake... I choose the color of the walls and the ground like (1, 0, 0) or (0, 0, 1)... Very stupid beginner mistake :D Additional i got another question. Is it right to divide by d^2? So the light intensity reduces by the distance? Thanks for helping me. Yes, ...
Fri Sep 27, 2013 12:37 pm
Forum: General Development
Topic: Path Tracing problem with indirect light
Replies: 7
Views: 5381

Re: Path Tracing problem with indirect light

I'm not sure of what the question is either. Yes, incoming indirect light should be multiplied by the surface BSDF, because there's a reflection at that point. If you do that with the colors you picked, you'll get pure black, but that's because you chose colors that don't really occur in nature. You...
Mon Sep 23, 2013 9:57 pm
Forum: General Development
Topic: Path Tracing and Reflective Shadow Maps
Replies: 4
Views: 4606

Re: Path Tracing and Reflective Shadow Maps

But what is with the point that RSM saves the shadow rays for the direct lighting? I don´t get it. For Example I have my RSM with some points on a ground. Now in my trace-routine I get an intersection point on the ground too. Do I have to search the RSM-list which point lays near to my intersection...
Fri Sep 20, 2013 3:36 pm
Forum: General Development
Topic: A note on PPM/VCM with specrtal rendering and motion blur
Replies: 9
Views: 7396

Re: A note on PPM/VCM with specrtal rendering and motion blu

Refractive index of real materials usually varies with wavelength, causing different wavelengths to refract at different angles. In the context of a smooth refractor (glass, water, younameit) that means the path with one wavelength will be invalid if you change the wavelength. I don't think the iss...
Wed Aug 21, 2013 6:01 pm
Forum: General Development
Topic: Speed Issues with GPU BVH rendering
Replies: 14
Views: 12628

Re: Speed Issues with GPU BVH rendering

Real-time doesn't mean that he cannot precompute his BVH structure (And load it at startup), fast BVH building is nice for animation but you can have real-time within a static scene (Or you can mix...). True. We don't really know a whole lot about the specific requirements. The OP implied that SBVH...
Wed Aug 21, 2013 4:27 pm
Forum: General Development
Topic: Speed Issues with GPU BVH rendering
Replies: 14
Views: 12628

Re: Speed Issues with GPU BVH rendering

1) The Aila & Laine use a "SBVH" (Split-BVH) that produce one of the best BVH structure you can find. It will be really faster than any other BVH. The structure creation is on the CPU. You can take a look at the following paper : https://mediatech.aalto.fi/~timo/publications/karras2013hpg_paper.pdf...
Sat Aug 10, 2013 1:53 am