moveBackward method
Implementation
void moveBackward(double amount) {
transform[POSX] += transform[BACKX] * amount;
transform[POSY] += transform[BACKY] * amount;
transform[POSZ] += transform[BACKZ] * amount;
}
void moveBackward(double amount) {
transform[POSX] += transform[BACKX] * amount;
transform[POSY] += transform[BACKY] * amount;
transform[POSZ] += transform[BACKZ] * amount;
}