"Most games are 95% art, 5% math, and 100% software."
You know it should add up to 100%? The game is generally a user taking the part of a character in a story. The storyline cannot be protected, but the diaglogue can be copyrighted. The art is also copyrighted so nobody else can copy the characters you created. The math cannot be protected, but your actual bytecode implementation of that math can be copyrighted.
No patents are necessary for software, and haven't been since software was invented.
"Gravity isn't patentable. An elevator is."
"Momentum isn't patentable. A brake system is."
As long you have a novel mechanical effect that nobody has ever thought of. However, the important bit is the "including mathematics"
"Division isn't patentable. eBay's feedback system is."
No sane system would allow such a patent. Only in the US.
"Light reflection isn't patentable. The way Blender simulates reflection is, if it's novel."
Again it breaks down into two parts: the mathematical algorithms used and the software written to implement those algorithms. Neither should be patentable. The latter is copyrighted and protected under the GPL.