set pixel on screen

COLORREF *arr = (COLORREF*) calloc(512*512, sizeof(COLORREF));
/* Filling array here */
/* ... */

// Creating temp bitmap
HBITMAP map = CreateBitmap(512 // width. 512 in my case
                           512, // height
                           1, // Color Planes, unfortanutelly don't know what is it actually. Let it be 1
                           8*4, // Size of memory for one pixel in bits (in win32 4 bytes = 4*8 bits)
                           (void*) arr); // pointer to array
// Temp HDC to copy picture
HDC src = CreateCompatibleDC(hdc); // hdc - Device context for window, I've got earlier with GetDC(hWnd) or GetDC(NULL);
SelectObject(src, map); // Inserting picture into our temp HDC
// Copy image from temp HDC to window
BitBlt(hdc, // Destination
       10,  // x and
       10,  // y - upper-left corner of place, where we'd like to copy
       512, // width of the region
       512, // height
       src, // source
       0,   // x and
       0,   // y of upper left corner  of part of the source, from where we'd like to copy
       SRCCOPY); // Defined DWORD to juct copy pixels. Watch more on msdn;

DeleteDC(src); // Deleting temp HDC