Bitwise_example.cpp

#include <bitset>
#include <iostream>

void showXorOp() {

    uint8_t var  = 0xFF;    // 255
    uint8_t var1 = 0X0F;    // 15

    std::cout << (int)var    << "\t" << std::bitset<8>(var)        << std::endl;
    std::cout << (int)var1   << "\t" << std::bitset<8>(var1)       << std::endl;
    std::cout << "result"    << "\t" << std::bitset<8>(var ^ var1) << std::endl;
}

void showAndOp() {

    uint8_t var  = 0x05;    // 5
    uint8_t var1 = 0x03;    // 3

    std::cout << (int)var    << "\t" << std::bitset<8>(var)        << std::endl;
    std::cout << (int)var1   << "\t" << std::bitset<8>(var1)       << std::endl;
    std::cout << "result"    << "\t" << std::bitset<8>(var & var1) << std::endl;
}

void showOrOp() {

    uint8_t var  = 0x48;    // 72
    uint8_t var1 = 0xB8;    // 184

    std::cout << (int)var    << "\t" << std::bitset<8>(var)        << std::endl;
    std::cout << (int)var1   << "\t" << std::bitset<8>(var1)       << std::endl;
    std::cout << "result"    << "\t" << std::bitset<8>(var | var1) << std::endl;
}

void showNegOp() {

    uint8_t var = 0xFA;     // 250

    std::cout << (int)var    << "\t" << std::bitset<8>(var)        << std::endl;
    std::cout << "result"    << "\t" << std::bitset<8>(~var)       << std::endl;
}

void showMask() {

    uint32_t alphaMask = 0xFF000000; // Mask to obtain alpha byte
    uint32_t blueMask  = 0x00FF0000; // Mask to obtain blue byte
    uint32_t greenmask = 0x0000FF00; // Mask to obtain green byte
    uint32_t redMask   = 0x000000FF; // Mask to obtain red byte

    std::cout << "alphaMask" << "\t" << std::bitset<32>(alphaMask)  << std::endl; // Show the mask
    std::cout << "blueMask"  << "\t" << std::bitset<32>(blueMask )  << std::endl; // Show the mask
    std::cout << "greenmask" << "\t" << std::bitset<32>(greenmask)  << std::endl; // Show the mask
    std::cout << "redMask  " << "\t" << std::bitset<32>(redMask  )  << std::endl; // Show the mask

    //                     A B G R
    uint32_t abgrColor = 0x8CE90A03;    // The actual 32-bit color

    std::cout << "32bit Color"        << "\t" 
              << std::bitset<8>(0x8C) << "|"        // Alpha color
              << std::bitset<8>(0xE9) << "|"        // Blue  color
              << std::bitset<8>(0x0A) << "|"        // Green color
              << std::bitset<8>(0x03) << std::endl; // Red   color

    std::cout << "Alpha (Byte 1)" << "\t" << std::bitset<32>(abgrColor & alphaMask) << std::endl;
    std::cout << "Blue  (Byte 2)" << "\t" << std::bitset<32>(abgrColor & blueMask ) << std::endl;
    std::cout << "Green (Byte 3)" << "\t" << std::bitset<32>(abgrColor & greenmask) << std::endl;
    std::cout << "Red   (Byte 4)" << "\t" << std::bitset<32>(abgrColor & redMask  ) << std::endl;
}

void showShifting() {

    uint8_t var = 0x01;

    std::cout << "0x01      = " << std::bitset<8>(var)        << std::endl;
    std::cout << "0x01 << 1 = " << std::bitset<8>(var << 1 )  << std::endl;
    std::cout << "0x01 << 2 = " << std::bitset<8>(var << 2 )  << std::endl;
    std::cout << "0x01 << 3 = " << std::bitset<8>(var << 3 )  << std::endl;

    std::cout << "Shifting works the same way in the other direction" << std::endl;
    std::cout << "Check if a bit 8 is set!" << std::endl;

    var = 0x8A;

    std::cout << "Var       = " << std::bitset<8>(var)        << std::endl;
    std::cout << "Var >> 7  = " << std::bitset<8>(var >> 7)   << std::endl;

    bool isBitSet = var >> 7;

    if(isBitSet) {
        std::cout << "The bit was set!" << std::endl;
    } else {
        std::cout << "Oh no!" << std::endl;
    }
}

void showChopping() {

    uint32_t var = 0x8CE90A03;

    std::cout << "Var:\t\t" << std::bitset<32>(var) << std::endl;

    uint8_t pack[4];
    pack[0] = ( var  & 0x000000FF);
    pack[1] = ( var  & 0x0000FF00) >> 8;
    pack[2] = ( var  & 0x00FF0000) >> 16;
    pack[3] = ( var  & 0xFF000000) >> 24;

    std::cout << "Chopped bytes:\t" << std::bitset<8>(pack[0]) << " | " 
                                  << std::bitset<8>(pack[1]) << " | " 
                                  << std::bitset<8>(pack[2]) << " | " 
                                  << std::bitset<8>(pack[3]) << std::endl;

    uint32_t unpacked = pack[0] | (pack[1] << 8) | (pack[2] << 16) | (pack[3] << 24);

    std::cout << "Un-Chopped :\t" << std::bitset<32>(var) << std::endl;

    if(unpacked == var) {
        std::cout << "Success!" << std::endl;
    }
}

int main() {

    std::cout << " --- AND --- " << std::endl;
    showAndOp();

    std::cout << " --- OR --- " << std::endl;
    showOrOp();

    std::cout << " --- XOR --- " << std::endl;
    showXorOp();

    std::cout << " --- NEG --- " << std::endl;
    showNegOp();

    std::cout << " --- MASK --- " << std::endl;
    showMask();

    std::cout << " --- SHIFT --- " << std::endl;
    showShifting();

    std::cout << " --- CHOP --- " << std::endl;
    showChopping();
    return 0;
}