pachesantiago

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About pachesantiago

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  1. I uploaded a new video, is at youtube now : https://www.youtube.com/watch?v=AXnAkTmGPyE
  2. Ok so I think that for now, I'll keep with this thread, and discuss about it. Ask away! When I have it more polished, maybe I'll make an article. Also I plan to try to enter next year GDC. Can't hurt trying, plus according to the SIGGRAPH reviewers, I was really close to make it. AHR needs, as they pointed out, more polish and also compare it to other techniques.
  3. Today I found out I was rejected to present my technique at SIGGRAPH, so I'm now open to talk about the technique, but I don't know how to continue from here. Should I do a tutorial, some kind of article, a downloadable demo? Maybe try to integrate it with some enigne, like Unity or UDK? Should I make a new post here on GameDev? What are other places where I can make this idea public? If anyone can provide some suggestions, I would be really glad, as I said, I don't know where to move with this from now on. I'll continue improving it though.
  4. Just a quick post. I played a bit with raytraced shadows, using AHR. Here are some (preliminary) results:
  5. I managed to implement a better material model, one similar to the one found on Blender's Cycles render engine(pathtracing), but simplified. Only two types of materials exist. One is a Diffuse material, that has it's rays distributed around the normal hemisphere, and the other is a Glossy material, that has it's rays distributed around the reflection hemisphere.  A value in the [0,1] range defines how much angle does the rays have with the hemisphere base(the normal for Diffuse materials, the reflection vector for Glossy materials) Both materials can have their own tracing parameters, such as rays, samples per rays, samples displacement, etc, and can be combined as you like.   I'll try to upload a video tomorrow, but here are some screens. The screens show only a Glossy material, because is the most interesting one. More materials and combinations later. Also, to combine direct and indirect I'm just doing lerp(shadowMask,direct,indirect) that's why there's so much difference. I have to find a better way to mix the materials( that's up for the artists  ?) No blur       8 Samples Depth-Aware Gaussian blur       Well, that's it for today. If I don't get to post the video tomorrow, don't expect anything from me on the next two weeks. Exams period on college  .
  6. Thanks! Tried that, and it works better now. Still, I have some things to fix. Anyone knows something about the atomic average problem I mentioned earlier? Still struggling with that.
  7. Anyone have anything to say about the blur problem? I'm still fighting with that. I'm also having another problem, and I posted on Stack Overflow about it : http://stackoverflow.com/questions/23189808/interlocked-average-cas-not-working-on-hlsl I'm trying to remove the flickering of the light by storing it using atomic ops, but I can't get it to work correctly. Here's the code I'm using: [allow_uav_condition] while (true) { // Get old value uint old = irradianceVolume[vpos]; // Average float3 avg = saturate((UnpackR5G5B5A1(old) + irradiance) * 0.5f); uint final = PackR5G5B5A1(float4(avg, 1)); // Try to store uint ret = -1; InterlockedCompareExchange(irradianceVolume[vpos], old, final, ret); if (ret == old) break; } If anyone can say anything, I would really appreciate it.
  8. Well, I had been working on improving the scene representation, and I managed to increase performance by about 20% - 25% with just a 3 % increase in memory usage and a small increase in the GBuffer stage, but I believe I could tune it up to 30% - 35%. Also now reflections take into account the sky, and I added specular lighting to the GI calculation.    I'm having a problem though, and I wanted to ask you guys. I can't get the blur to work correctly. I'm implementing a Gaussian blur, separated on two passes, with the weights calculated on the fly, as I like to be able to tune the number of samples of the filter. Also, the Gaussian weight is multiplied by 1 / (epsilon + abs(z - depth[sample])) to take into account depth discontinuities. It works, but instead of producing a nice smooth blur, it creates a black cross in the middle. Below is a screen. Rays where reduced to 1 per pixel and strength upped to better display the problem. The blur is using 8 samples and a sigma of 4.3.     And here is the code for the horizontal pass. The vertical one is exactly the same, changing float2(1, 0) for float2(0, 1). I read two images, do the horizontal blur to two temp images, do the vertical blur sampling the temp images, and output to the original images. Texture2D<float> tCoarseDepth : register(t0); Texture2D<float4> tCoarseNormal : register(t1); Texture2D<float4> tGI : register(t2); Texture2D<float4> tRFL : register(t3); RWTexture2D<float4> output : register(u0); RWTexture2D<float4> outputRFL : register(u1); static const float samples = 8; static const float g_epsilon = 0.0001f; static const float sigma = 4.3f * 4.3f; [numthreads(256, 1, 1)] void BlurH( uint3 DTid : SV_DispatchThreadID ) { float z = tCoarseDepth[DTid.xy]; float4 gi = tGI[DTid.xy]; float4 rfl = tRFL[DTid.xy]; float acc = 1; float2 spos = float2(1, 0); for (float i = 1; i <= samples; i++) { // Sample right // Calculate weights float zWeightR = 1.0f / (g_epsilon + abs(z - tCoarseDepth[DTid.xy + spos*i])); float WeightR = zWeightR * GaussianWeight(i, sigma); // Sample gi += tGI[DTid.xy + spos*i]* WeightR; rfl += tRFL[DTid.xy + spos*i] * WeightR; acc += WeightR; // Sample left // Calculate weights float zWeightL = 1.0f / (g_epsilon + abs(z - tCoarseDepth[DTid.xy - spos*i])); float WeightL = zWeightL * GaussianWeight(i, sigma); // Sample gi += tGI[DTid.xy - spos*i] * WeightL; rfl += tRFL[DTid.xy - spos*i] * WeightL; acc += WeightL; } output[DTid.xy] = gi / acc; outputRFL[DTid.xy] = rfl / acc; } If someone can shed some light, I would be grateful. There's other thing I want / need to add to my blur shader, and that is to take into account the distance of the pixel, so everything gets the same amount of blur. Right now, things that are too far get too much blur, and things that are to close don't get enough. I need suggestion on how to do that, I suppose someone here has done it before. Well, that's it for now, I'll try to keep this thread with some more regular updates, maybe a screen every two or three days. EDIT: Here's the code for the GaussianWeight function   float GaussianWeight(float x,float sigmaSquared) { float alpha = 1.0f / sqrt(2.0f * 3.1416f * sigmaSquared); float beta = (x*x) / (2*sigmaSquared); return alpha*exp(-beta); }
  9. Well, I ran into some unexpected problems, so it took more than I though. Here are some screens of a dirty simple Cornell Box:   I disabled reflections, as I had some problems getting them to look good on that scene. Just GI for now. The blur needs a lot of work too, but I believe the idea is there. As you can see by the FPS, my poor GTX 750 Ti is trying it's best, but is not enough. the 75 W TDP and mainly the 128 bits bus really hurts performance, as this is a bandwidth-bound algorithm. I ran it a couple times on a 7870, and it runs at twice or more framerate ( 256 bit bus ).  It depends a lot on the scene and the settings, but I cant get 30 FPS with the 750 Ti at the Sponza scene( wich is actually faster, as a lot of rays collide really close to the start position) EDIT: Does anyone knows how can I put an images album? Or at least the images one by one, nothing seems to work. For now, here goes the link https://imgur.com/a/T0SJP
  10. Great then! I should have that scene ready in a couple hours
  11. I totally understand your point, I know it's hard to talk about something not knowing how it works. Also, I'm all in for constructive criticism. Now to the scene related things: You said you'll like to see different materials, I think I can put together a scene with a bunch of spheres with different reflection amount, gi amount, etc in the next couple hours. Is that what you had in mind? Regarding the reflections, is mostly the fact I had quite a problem combining the GI , Reflections and Direct Illumination buffers, and making it look good, but is more of an "artistical" problem of sorts 
  12. I'm sorry, but I don't want to get into implementation details ( ) until I know if I'm accepted / rejected to present at SIGGRAPH. I can say that I don't use acceleration structures per se , it's more like a brute force raytracer. Next month I should know the verdict, and I'll get into details then. Hope you understand.
  13. Hy everyone, I had been working for the last few months in a method to render reflections / GI  ( and other things too) at real time in mid range hardware, and a few days back I finished a presentation video and applied to the Real Time Live! conference at SIGGRAPH. Because of that I can't talk details now, but I wanted to show what I had accomplished. The video is below: https://www.youtube.com/watch?v=dL_SxY2Njq4   As I said at the description, the demo actually runs more fluent, but Camtasia took some of it away. Anyway, what I can say is that is a combination of standard rasterization and raytracing, supports fully dynamic scenes, doesn't requires extra passes on the geometry( well, the triangles are duplicated, but inside a geometry shader), and is really simple to implement, which leaves a lot of room for improvement and new techniques based on it.
  14. Best way to filter for a bloom effect

    [quote name='pachesantiago' timestamp='1350324376' post='4990455'] hy. im using this to in my bloom shader. is simple and it works really well [CODE] float4 color = tex2D( srcTex, IN.uv ); color = (-color + (pow(tex2D( srcTex, IN.uv ),Power) * Scale) )/Bias; return color; [/CODE] here's a screenshot using scale = 1.83, power = 4 and bias = 0.27 [url="http://imgur.com/WXed6"][img]http://i.imgur.com/WXed6.jpg[/img][/url] PS: this is HLSL, but i think it should be really similar [/quote] Sorry, didnt mention that the grayscale is another shader, is not part of the "bright pass" Using colors: [URL=http://imgur.com/21Oys][IMG]http://i.imgur.com/21Oys.png[/IMG][/URL]
  15. Best way to filter for a bloom effect

    hy. im using this to in my bloom shader. is simple and it works really well [CODE] float4 color = tex2D( srcTex, IN.uv ); color = (-color + (pow(tex2D( srcTex, IN.uv ),Power) * Scale) )/Bias; return color; [/CODE] here's a screenshot using scale = 1.83, power = 4 and bias = 0.27 [URL=http://imgur.com/WXed6][IMG]http://i.imgur.com/WXed6.jpg[/IMG][/URL] PS: this is HLSL, but i think it should be really similar