Function FaceOffset

common/dds.cpp:836–865

static int FaceOffset( const DDSHeader & header )
{

    DDSType type = GetType( header );

    int mipmap = qMax(header.mipmapcount, 1U);
    int size = 0;
    int w = header.width;
    int h = header.height;

    if( type >= DDS_DXT1 ) {
        int multiplier = (type == DDS_DXT1) ? 8 : 16;
        do {
            int face_size = qMax(w/4,1) * qMax(h/4,1) * multiplier;
            size += face_size;
            w >>= 1;
            h >>= 1;
        } while( --mipmap );
    } else {
        int multiplier = header.pf.bitcount / 8;
        do {
            int face_size = w * h * multiplier;
            size += face_size;
            w = qMax( w>>1, 1 );
            h = qMax( h>>1, 1 );
        } while( --mipmap );
    }

    return size;
}

#if CUBE_LAYOUT == HORIZONTAL
static int face_offset[6][2] = { {2, 1}, {0, 1}, {1, 0}, {1, 2}, {1, 1}, {3, 1} };