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  • #31
    Originally posted by V!NCENT View Post
    You don't get the point... How about a complete forest with 3D modelled grass?
    Actually that's something rasterisation has problems with - nice looking grass, and leaves (do note that I haven't played crysis). Most engines simply have a a few quads with alpha-blended textures on there, but you can still see that it's just rows of textured quads.
    Only I'm not sure how raytracing will improve it much. Dunno, it's just something I'd like to see improvement on (I do have some ideas, but none have panned out properly so far).

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    • #32
      Originally posted by mirv View Post
      Actually that's something rasterisation has problems with - nice looking grass, and leaves (do note that I haven't played crysis). Most engines simply have a a few quads with alpha-blended textures on there, but you can still see that it's just rows of textured quads.
      That's the point; Crysis uses two triangle-textured grass and it stresses even the current graphics offering to its limits.

      Only I'm not sure how raytracing will improve it much. Dunno, it's just something I'd like to see improvement on (I do have some ideas, but none have panned out properly so far).
      Ray tracing will eventually reach a point that it's faster than triangle rendering. Allthough the shadow rays really eat into the calculation power of the CPU :P

      But whatever... in three years this can be mixed with OpenCL and it won't be a problem...
      Last edited by V!NCENT; 15 October 2009, 07:20 AM.

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      • #33
        Originally posted by V!NCENT View Post
        Ray tracing will eventually reach a point that it's faster than triangle rendering.
        No, it won't. Re-read the Carmack quote I posted earlier in the context of this statement of yours.

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        • #34
          Originally posted by yogi_berra View Post
          No, it won't. Re-read the Carmack quote I posted earlier in the context of this statement of yours.
          First of all ray tracing scales 1 on 1 with more cores. The only, and then I mean the only advantage of rasterization right now is parralell execution. And that is the only advantage of todays graphics cards, because serial execution on these cards is slow as hell compared to that of a CPU. That said, CPU's will get more power than a graphics card over time by getting more cores (derivative of Moore's law today that Intel is pushing), but the cores will also get more efficient over time.

          Rasterization is slower, way slower, with softpipe rendering on a CPU than raytracing on a CPU. So what are we even talking about?

          And that's on general purpose HW. Just wait untill there will be dedicated ray tracing cards. It will kick the shit out of rasterizing graphics cards.

          Carmack is a genious, but (and here comes the teapot refference I made earlyer) if I would make a NURBS model with smooth surfaces and render it with raytracing than in order to get a pixel-perfect rasterization equivilent (geometry here) than that would take so much triangles that it clearly shows that raytracing is indeed much, much, much faster.
          Last edited by V!NCENT; 16 October 2009, 11:28 AM.

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          • #35
            Well I'll have to disagree with software ray-tracing faster than software rasterisation (otherwise original software renderers would have been ray traced). Graphics were of course much simpler then, but the pixel shader step is extremely quick, and something that's also highly parallel.
            There's also the issue of throwing cores at a problem only does so much good - practical issues such as cache synchronisation when updating data structures will slow things down.
            Last edited by mirv; 16 October 2009, 03:43 PM. Reason: tzping when tired....

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            • #36
              Originally posted by V!NCENT View Post
              Rasterization is slower, way slower, with softpipe rendering on a CPU than raytracing on a CPU. So what are we even talking about?
              If this were truly the case, the kitchen in the Pixar film Ratatouille would have used raytracing for the numerous reflections instead of brickmapping. The brickmapped (rasterized) reflections dropped render times remarkably, Pixar published papers about it, do some research on your own, you'll be surprised what you may learn

              You do, however, need to rethink your position, namely because it appears as if you are making the assumption that rasterization techniques will suddenly stop being efficient once the perfect storm of CPU and GPU cores is reached.

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              • #37
                Originally posted by mirv View Post
                Well I'll have to disagree with software ray-tracing faster than software rasterisation (otherwise original software renderers would have been ray traced).
                Back in the days that graphics card started going 3D the foundation had alreeady been layed out and improved because crappy rasterization was just fast enough to just run. That's why you have rasterization cards today instead of dedicated raytracing graphics cards.

                Graphics were of course much simpler then, but the pixel shader step is extremely quick, and something that's also highly parallel.
                That is surely a nice addition

                There's also the issue of throwing cores at a problem only does so much good - practical issues such as cache synchronisation when updating data structures will slow things down.
                Parallelization is needed to have decent rendering speeds and te rendering only reads out the data and then puts it into the framebuffer and not a single synchronization is needed. That is the entire point

                Originally posted by yogi_berra View Post
                If this were truly the case, the kitchen in the Pixar film Ratatouille would have used raytracing for the numerous reflections instead of brickmapping. The brickmapped (rasterized) reflections dropped render times remarkably, Pixar published papers about it, do some research on your own, you'll be surprised what you may learn
                Then tell me why the FPS of Quake 3 over softpipe rendering is slower than a ray tracing benchmark? Do the calculations and see for yourself. And the research? ROFL. Even my grandmother could figure out that degrading image quality takes less computational costs.

                You do, however, need to rethink your position, namely because it appears as if you are making the assumption that rasterization techniques will suddenly stop being efficient once the perfect storm of CPU and GPU cores is reached.
                If you have read the entire thread that you would have known by now that Raytracing can get better graphics at less additional computational costs.

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                • #38
                  Originally posted by V!NCENT View Post
                  If you have read the entire thread that you would have known by now that Raytracing can get better graphics at less additional computational costs.
                  No, however, reading the entire thread does tell me that you have no experience in graphics and rather than relying on firm data, you prefer to resort to playground tactics to silence people that disagree with you.

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                  • #39
                    Originally posted by yogi_berra View Post
                    No, however, reading the entire thread does tell me that you have no experience in graphics and rather than relying on firm data, [...]
                    Data = information = IT = information technology = programming
                    So uhh... what is your point? :S

                    [...] you prefer to resort to playground tactics to silence people that disagree with you.
                    Playground tactics? I have responded with constructive arguments to points and problems raised/that have been made and if I have been playing around these issues than when somebody asked to give constructive arguments isntead of just saying "You are wrong" than I have done that.

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                    • #40
                      VINCENT,

                      It is uncommon to come across someone who is so, errr... sure of himself, as to think they can singlehandedly best the efforts of an entire well-funded research community. I must say, in this day and age, it's not likely to happen. However, perhaps you have some solid insight; I don't work in computer graphics so I'm not qualified to comment. What I do know from my own community is that first-order logical arguments aren't going to convince anyone - you need something which works and can be measured.

                      Given the situation, I think you're likely to find there are hurdles blocking your approaches or which nullify any perceived advantages. Do be sure you have a solid foundation on which to base your work.

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