float OctreeHash::Node::getZ(){
float shift_factor = this->parent->initialD/4;
float result = this->parent->initialD/2;
unsigned char bitscount = numberOfBits();
if ( bitscount < 4 )
return result;
for( unsigned long i = 1 << (bitscount-3), bits = 2; bits < bitscount; i >>= 3, bits += 3, shift_factor /= 2){
if ( i & id ){
result += shift_factor;
}
else{
result -= shift_factor;
}
}
return result;
}
bool bit_test(unsigned int x, int n)
{
/*algorithm:
*1. j = numberOfBits(x)
*2.temp = 1 << j (left shift 1 j times to place bit on the left)
*3.temp = temp >> n
*3.temp & x == temp if n bit is set
*/
int j = numberOfBits(x);
unsigned int temp = 1 << (j - 1);
temp = temp >> n;
if ((temp & x) == temp) //nbit is set
return true;
else
return false;
}
int main (void)
{
unsigned int x, n;
printf("Number of bits for u int : %i\n", int_size());
printf("Enter int x and bit number to test: ");
scanf("%u %u", &x, &n);
printf("Number of bits in %i is %i\n", x, numberOfBits(x) );
if (bit_test(x,n))
printf("Bit %i is set on %i\n", n,x);
else {
printf("Bit %i is not set, setting...\n", n);
x = bit_set(x,n);
printf("New value of x: %i\n", x);
}
return 0;
}
inline T floorPowerOf2(T x)
{
for (T i = 1; i < numberOfBits(x); i += i)
x |= (x >> i);
return x - (x >> 1);
}
void QSslKeyPrivate::decodeDer(const QByteArray &der, bool deepClear)
{
clear(deepClear);
if (der.isEmpty())
return;
QAsn1Element elem;
if (!elem.read(der) || elem.type() != QAsn1Element::SequenceType)
return;
if (type == QSsl::PublicKey) {
// key info
QDataStream keyStream(elem.value());
if (!elem.read(keyStream) || elem.type() != QAsn1Element::SequenceType)
return;
QVector<QAsn1Element> infoItems = elem.toVector();
if (infoItems.size() < 2 || infoItems[0].type() != QAsn1Element::ObjectIdentifierType)
return;
if (algorithm == QSsl::Rsa) {
if (infoItems[0].toObjectId() != RSA_ENCRYPTION_OID)
return;
// key data
if (!elem.read(keyStream) || elem.type() != QAsn1Element::BitStringType || elem.value().isEmpty())
return;
if (!elem.read(elem.value().mid(1)) || elem.type() != QAsn1Element::SequenceType)
return;
if (!elem.read(elem.value()) || elem.type() != QAsn1Element::IntegerType)
return;
keyLength = numberOfBits(elem.value());
} else if (algorithm == QSsl::Dsa) {
if (infoItems[0].toObjectId() != DSA_ENCRYPTION_OID)
return;
if (infoItems[1].type() != QAsn1Element::SequenceType)
return;
// key params
QVector<QAsn1Element> params = infoItems[1].toVector();
if (params.isEmpty() || params[0].type() != QAsn1Element::IntegerType)
return;
keyLength = numberOfBits(params[0].value());
}
} else {
QVector<QAsn1Element> items = elem.toVector();
if (items.isEmpty())
return;
// version
if (items[0].type() != QAsn1Element::IntegerType || items[0].value().toHex() != "00")
return;
if (algorithm == QSsl::Rsa) {
if (items.size() != 9 || items[1].type() != QAsn1Element::IntegerType)
return;
keyLength = numberOfBits(items[1].value());
} else if (algorithm == QSsl::Dsa) {
if (items.size() != 6 || items[1].type() != QAsn1Element::IntegerType)
return;
keyLength = numberOfBits(items[1].value());
}
}
derData = der;
isNull = false;
}
