Vector swizzles :)

gistfile1.py

#http://stackoverflow.com/questions/16446374/generating-all-permutations-with-repetition
alphabet = [ 'x', 'y', 'z', 'w' ]

def symbolic_increment( symbol, alphabet, num_items):
    ## increment our "symbolic" number by 1
    symbol = list(symbol)
    ## we reverse the symbol to maintain the convention of having the LSD on the "right"
    symbol.reverse()
    place = 0;
    while place < len(symbol):
        if (alphabet.index(symbol[place])+1) < num_items:
            symbol[place] = alphabet[alphabet.index(symbol[place])+1]
            break
        else:
            symbol[place] = alphabet[0];
            place+=1
    symbol.reverse()
    return ''.join(symbol)

def toVec(symbol):
    num = len(symbol)
    if (num == 2):
        return "AGVec2(%s,%s)" % (symbol[0], symbol[1])
    elif (num == 3):
        return "AGVec3(%s,%s,%s)" % (symbol[0], symbol[1], symbol[2])
    else:
        return "AGVec4(%s,%s,%s,%s)" % (symbol[0], symbol[1], symbol[2], symbol[3])

def gen(fromClass, toClass, fromComponents, toComponents):
    permutations=[]
    r = toComponents
    start_symbol = alphabet[0] * (r)
    temp_symbol = alphabet[0] * (r)
    while 1:
        permutations.append(temp_symbol)
        print "%s %s() const { return %s; }" % (toClass, temp_symbol, toVec(temp_symbol))
        temp_symbol = symbolic_increment( temp_symbol, alphabet, fromComponents)
        if( temp_symbol == start_symbol ): break
    print "Generated %d permutations" % len(permutations)

#gen("AGVec2", "AGVec2", 2, 2)

#gen("AGVec3", "AGVec2", 3, 2)
#gen("AGVec3", "AGVec3", 3, 3)

gen("AGVec4", "AGVec2", 4, 2)
gen("AGVec4", "AGVec3", 4, 3)
gen("AGVec4", "AGVec4", 4, 4)