Blur Busters Forums

Since I posted the earlier links (listed in Excellent article by NVIDIA VR scientist) about NVIDIA reinventing the display pipeline...

...the day appears to be getting closer and closer.

Real-Time Raytracing Announcements by Microsoft, NVIDIA and AMD









...Now if only we can get this during low-persistence operation and/or full 240 Hz framerates!

I never understood what ray tracing is and how it is different from normal 3d polygon based rendering ?
With ray tracing the only difference I see is that it's crazy demanding and that everything is shiny. Every single object in those demos always is a mirror and has a million polygons

lexebidar wrote:I never understood what ray tracing is and how it is different from normal 3d polygon based rendering ?

Well, a couple videos on the subject:

https://www.youtube.com/watch?v=Qx_AmlZxzVk

https://www.youtube.com/watch?v=DtfEVO9Oc3U

Obviously we're not going to get full ray tracing here, just partially for some elements; full ray tracing just isn't doable in real time. But in general, ray tracing can generate images that actually match reality, while rasterization cannot do that and requires special effects to "fake" things like lighting, shadows and reflections.

lexebidar wrote:I never understood what ray tracing is and how it is different from normal 3d polygon based rendering ?
With ray tracing the only difference I see is that it's crazy demanding and that everything is shiny. Every single object in those demos always is a mirror and has a million polygons

Basically, ray tracing simulates light bouncing around a room from light sources to the camera. Everything is shiny because that's something that's difficult to do with more traditional rendering techniques.

Instead of chopping a sphere up into a whole bunch of polygons, you just calculate what direction the photon would have gone, with what probability.

It's the same as photons bouncing around, everything reflects light, therefor everything is shiny. The colour of the wall reflecting onto another wall or floor is a pretty neat effect. All of the effect games devs do to fake real life lighting (Ambient occlusion/Reflections) doesn't need to be faked when you ray-trace the light.