Zooming In on a Selection: Step 7

In the MainWndProc function, add code to process WM_RBUTTONDOWN messages. This code displays the full image when the user clicks the right mouse button. During testing, this lets you try the selection feature more than once. The code should appear as follows:

case WM_RBUTTONDOWN:
   /* Set the source rectangle for painting */
   SetRect(&rLeadSource, 0, 0, LeadBitmap.Width, LeadBitmap.Height);
   /* Make the destination rectangle for painting the same as the client area */
   rLeadDest = rClientSize;
   /* Update the global variables for keeping track of the display */
   DisplayLeft = 0;
   DisplayTop = 0;
   DisplayWidth = rClientSize.right;
   DisplayHeight = rClientSize.bottom;
   /* Repaint the whole client area */
   InvalidateRect(hWnd,NULL,FALSE);
   return (0);