Ray Tracing To Debut in DirectX 11

crazyeyes writes "This is breaking news. Microsoft has not only decided to support ray tracing in DirectX 11, but they will also be basing it on Intel's x86 ray-tracing technology and get this ... it will be out by the end of the year! In this article, we will examine what ray tracing is all about and why it would be superior to the current raster-based technology. As for performance, well, let Intel dazzle you with some numbers. Here's a quote from the article: 'You need not worry about your old raster-based DirectX 10 or older games or graphics cards. DirectX 11 will continue to support rasterization. It just includes support for ray-tracing as well. There will be two DirectX 11 modes, based on support by the application and the hardware.'"

Re:John Carmack on Ray Tracing

[Azarael]

There's this one from PC Perspective as well which is an interview with NVidia's Tech Director:
http://www.pcper.com/article.php?aid=530/ [pcper.com]

His view on ray tracing is pretty much summed up by:

David Kirk, NVIDIA: I'm not sure which specific advantages you are referring to, but I can cover some common misconceptions that are promulgated by the CPU ray tracing community. Some folks make the argument that rasterization is inherently slower because you must process and attempt to draw every triangle (even invisible ones)--thus, at best the execution time scales linearly with the number of triangles. Ray tracing advocates boast that a ray tracer with some sort of hierarchical acceleration data structure can run faster, because not every triangle must be drawn and that ray tracing will always be faster for complex scenes with lots of triangles, but this is provably false.

There are several fallacies in this line of thinking, but I will cover only two. First, the argument that the hierarchy allows the ray tracer to not visit all of the triangles ignores the fact that all triangles must be visited to build the hierarchy in the first place. Second, most rendering engines in games and professional applications that use rasterization also use hierarchy and culling to avoid visiting and drawing invisible triangles. Backface culling has long been used to avoid drawing triangles that are facing away from the viewer (the backsides of objects, hidden behind the front sides), and hierarchical culling can be used to avoid drawing entire chunks of the scene. Thus there is no inherent advantage in ray tracing vs. rasterization with respect to hierarchy and culling. /blockquote

Re:OpenGL

[Yetihehe]

There is now only OpenRT which have Open only fro similarity with OpenGL (it is fully proprietary implementation, but has API similar to that of OpenGL).

OpenGL? Not gonna happen...

[Joce640k]

a) OpenGL is an immediate-mode API - it doesn't store a "scene" it just processes a single polygon at a time.

b) You can't raytrace something unless you have access to the whole scene.

QED.

Re:Only available with Windows 7

[vikstar]

Anyone who has knows a bit about computer graphics will suspect this is a joke from the heading itself, and then when you look at the ray-traced image comparison all doubt is removed (especially because it seems to use global illumination). I was just upset they didn't spend more time on it. The joke could've been much better, showing realistic-looking specs, small rendering times etc.