A guide for the impatient:

GPU = CPU, but one that is placed specifically on the graphics card, and one that may specifically be optimized to perform instructions related to 3D calculations faster than other instructions.

As far as the 3D stuff, don't think "3D", instead think Math specifically related to 3D.

OK, so what is that Math?

Well, we could consult Stack Overflow for that:

https://stackoverflow.com/questions/1320403/math-used-in-3d-...

OK, so next question, what does a GPU do then?

Well, remember that a CPU can run any generalized algorithmic computations -- including those required for 3D graphics(!) (they are Turing-Complete, after all!), but the thing is, 3D graphics cards have their GPU's, er, CPU's, er, GPU's -- specifically optimized in various different ways (parallelism, specific instruction types, etc.) for the mathematics of 3D.

So you see, what is being searched for is as follows:

The fastest CPU, er, GPU, er CPU, that can be created on an FPGA, that can be optimized for specific 3D MATH operations, that can be created patent-free.

Now, here's the thing...

In Mathematics, TMTOWTDI (There's more than one way to do it) -- is King.

While some math algorithms (side philosophical question to self, "How does anyone patent MATH?". No really, how do they do it? That idea is utterly mind boggling and self-contradictory! It's like what the Principal said to Billy Madison: "Mr. Madison, what you've just said is one of the most insanely idiotic things I have ever heard. At no point in your rambling, incoherent response were you even close to anything that could be considered a rational thought. Everyone in this room is now dumber for having listened to it. I award you no points, and may God have mercy on your soul."), while some math algorithms implemented in hardware are patented (and possibly still under patent) -- there are many others that are not!

In other words, there are other ways to get the job done...

Some good starting points might be to read up on the 3D hardware in the original Playstation (1994) https://en.wikipedia.org/wiki/PlayStation_technical_specific...

>"Geometry Transformation Engine (GTE)

Coprocessor [PDS: aka "GPU"] that resides inside the main CPU processor, giving it additional vector math instructions used for 3D graphics, lighting, geometry, polygon and coordinate transformations – GTE performs high-speed matrix multiplications.

Well, there we go, there's the start of the 3D math part, vector math instructions and high-speed matrix multiplications.

Then there is "Fused Multiply Add", aka "Multiply Accumulate Operation":

https://en.wikipedia.org/wiki/Multiply%E2%80%93accumulate_op...

>"A fast FMA can speed up and improve the accuracy of many computations that involve the accumulation of products:

Dot product
Matrix multiplication
Polynomial evaluation"

PDS: Which would be used in 3D Graphics acceleration...

Anyway, those are the starting points to look into if someone wants to "leap off" into this area...

This is an interesting topic; it sort of exists as confluence of several disciplines -- including Digital Logic Engineering, Algorithms, Law and Math...

(But seriously, how does anyone patent MATH itself? I mean, seriously! <g>)