#ifndef UTILS_COMP #define UTILS_COMP // mod and div are expensive and coordinates/dimensions are often power of 2 or equal to 1 uint fastmod(uint a, uint b) { if ((b & (b-1)) == 0) { return a & (b-1); } return a % b; } uint fastdiv(uint a, uint b) { return (a < b) ? 0 : (a / b); } void get_indices(uint idx, out uint i00, out uint i01, out uint i02, out uint i03, uint ne00, uint ne01, uint ne02, uint ne03) { i03 = fastdiv(idx, (ne02*ne01*ne00)); const uint i03_offset = i03 * ne02*ne01*ne00; i02 = fastdiv((idx - i03_offset), (ne01*ne00)); const uint i02_offset = i02*ne01*ne00; i01 = (idx - i03_offset - i02_offset) / ne00; i00 = idx - i03_offset - i02_offset - i01*ne00; } #endif // UTILS_COMP