Analysis on Intel’s Larrabee architecture
Let’s think about this for a second. Intel is using a complete x86 CPU architecture, albeit with necessary bolt-ons such as the 16-wide ALU unit, to run graphics. What that really means is that rendering takes place in software. Yup, you’ve read that right: Larrabee uses massive parallel power to software-run code.
So, after input data has been provided, vertex shading; geometry shading; primitive setup; rasterisation; pixel shading; and blending – the step-by-step building blocks of a modern GPU – are all done in software in Larrabee, rather than, in the main, shading, as it is on current NVIDIA or ATI cards.
Intel reckons that this makes Larrabee fully programmable and far more suited to future workloads, but such an approach comes at the inevitable cost of having developers natively code for Larrabee using a C/C++ API. The ‘problem’ is somewhat mitigated by the fact that coding shouldn’t be too different than writing for x86, which, after all, is what Larrabee is based upon.