grad() [2/4]

static int32_t grad ( uint8_t hash, int32_t x, int32_t y )

static

Definition at line 79 of file simplex.cpp.

                                                        {
    uint8_t h = hash & 7;      // Convert low 3 bits of hash code
    int32_t u = h < 4 ? x : y; // into 8 simple gradient directions,
    int32_t v = h < 4 ? y : x; // and compute the dot product with (x,y).
    return ((h&1) != 0 ? -u : u) + ((h&2) != 0 ? -2*v : 2*v);
}

References x, and y.