Visual C++ and MFC Programming 2nd Edition

Visual C++ and MFC Fundamentals Chapter 8 GDI Orientation and Transformations

7.6.4 Patterned Brushes................................................................................

A pattern brush is one that uses a bitmap or (small) picture to fill out an area. To create

DDB bitmap, you can first create an array of WORD values. Then call the

CBitmap::CreateBitmap() method to initialize it. As this makes the bitmap ready, call

the CBrush::CreatePatternBrush() method to initialize the brush. The syntax of this

member function is:

BOOL CreatePatternBrush(CBitmap* pBitmap);

Once the brush has been defined, you can select in into a device context and use it as you

see fit. For example, you can use it to fill a shape. Here is an example:

void CCView4View::OnDraw(CDC* pDC)

{

CCView4Doc* pDoc = GetDocument();

ASSERT_VALID(pDoc);

CBitmap Bmp;

CBrush brBits;

WORD wBits[] = { 0x00, 0x22, 0x44, 0x88, 0x00, 0x22, 0x44, 0x88,

0x22, 0x44, 0x88, 0x00, 0x22, 0x44, 0x88, 0x00,

0x44, 0x88, 0x00, 0x22, 0x44, 0x88, 0x00, 0x22,

0 x88, 0x00, 0x22, 0x44, 0x88, 0x00, 0x22, 0x44 };

Bmp.CreateBitmap(32, 32, 1, 1, wBits);

brBits.CreatePatternBrush(&Bmp);

CBrush* pOldBrush = (CBrush*)pDC->SelectObject(&brBits);

pDC->Rectangle(20, 20, 400, 400);

pDC->SelectObject(&Bmp);

}

Another technique you can use to create a pattern brush consists of using a bitmap

resource. Before creating a pattern, you must first have a picture, which can be done by

creating a bitmap. For example, imagine you create the following bitmap: