Kyle Hayward, a Purdue University senior studying graphics research who we've featured before, posted a useful primer to dual-paraboloid reflections, which he describes as a "view-independent method of rendering reflections just like cubemaps."

Unlike cubemaps, which can require updating up to six textures when rendering dynamic scenes, dual-paraboloid reflections only require updating two textures.

Hawyard comments: "They won't give you the quality of cubemaps, but they are faster to update and require less memory. And in the console world, requiring less is almost reason enough to pick this method over cubemaps."

He goes on to share several reference articles and a math overview before providing code for developers to experiment with generating their own reflections with paraboloid maps.

Hayward notes that there are a couple faults to watch out for in addition to reduced quality: "One drawback of paraboloid maps is that the environment geometry has to be sufficiently tessellated or we will have noticeable artifacts on our reflector. Another drawback is that on spherical objects, we will see seems. However, with objects that have convex and concave polygons, the seem won't be as noticeable."

Posted by Eric Caoili at 01:54 PM | Permalink

Intel senior software engineer Gary Carleton returns for this week's featured video to again discuss Intel's software development tools, this time demonstrating the Intel Thread Profiler and the Thread Building Blocks.

With the Intel Thread Profiler, developers can see lock transitions for a program and when threads are active on a particular core. Carleton explained, "You can kind of get a sense of how much lock thrashing or lock activity is occurring and maybe get a visual look at how much synchronization overhead is occurring with the application."

Developers can also click on a particular thread transition to look at the source code for both the thread releasing the lock and the thread acquiring the lock. That way, they can examine the code if they feel that there's too much lock activity occurring.

Said Carleton, "The goal is to measure the amount of parallelization of the system [to see if we] are in fact using all the execution cores in the system, and then to be able to drill down into more detail as to how the threads are interacting."

Posted by Eric Caoili at 01:06 PM | Permalink