C++ Adding 2 arrays together quickly

Question

Given the arrays:

int canvas[10][10];
int addon[10][10];

Where all the values range from 0 - 100, what is the fastest way in C++ to add

Answer 1

Two parts: first, consider your two-dimensional array [10][10] as a single array [100]. The layout rules of C++ should allow this. Second, check your compiler for intrinsic functions implementing some form of SIMD instructions, such as Intel's SSE. For example Microsoft supplies a set. I believe SSE has some instructions for checking against a maximum value, and even clamping to the maximum if you want.