LRasterPaint::RegionEllipse

#include "Ltwrappr.h"

L_INT LRasterPaint::RegionEllipse(UserDC, prcRect, phDestRgn)

HDC UserDC;	/* handle to the device context */
LPRECT prcRect;	/* pointer to a RECT structure */
pHRGN phDestRgn;	/* pointer to a region handle */

Creates an elliptical region using the bounding rectangle, specified in prcRect.

Parameter	Description
UserDC	Handle to a device context, such as a screen, to use as a display surface. This parameter can also be NULL. The mapping mode of the device context must be MM_TEXT.
prcRect	Pointer to a RECT structure that specifies the region boundaries
phDestRgn	Pointer to the region handle to be updated with the resulting region.

Returns

SUCCESS	The function was successful.
< 1	An error occurred. Refer to Return Codes

Comments

The region creation procedure will be carried out using the current region properties. To determine the current region properties, call LRasterPaint::GetProperty. To set or change the current region properties, call LRasterPaint::SetProperty. For more information on the region properties, refer to the PAINTREGION structure.

This function will also use the current painting transformation information when creating the new region. To get the current painting transformation information, call LRasterPaint::GetTransformation. To change or set the painting transformation information, call LRasterPaint::SetTransformation.

If the user has set a bitmap in the toolkit, using the function LRasterPaint::SetMetrics, then the toolkit will create the region for the bitmap. Otherwise, the toolkit will create the region for the specified device context.

Required DLLs and Libraries

LTPNT

For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application

See Also

Functions:

LRasterPaint::SetProperty, LRasterPaint::SetTransformation, LRasterPaint::SetDCExtents, LRasterPaint::SetMetrics, LRasterDialog::DoModalRegion, LRasterPaint::GetClipRgn, LRasterPaint::OffsetClipRgn, LRasterPaint::RegionBorder, LRasterPaint::RegionColor, LRasterPaint::RegionPolygon, LRasterPaint::RegionRect, LRasterPaint::RegionRoundRect, LRasterPaint::RegionScale, LRasterPaint::RegionSurface, LRasterPaint::RegionTranslate, LRasterPaint::SetClipRgn, Class Members

Topics:

Creating a Region

Example

L_INT OnRegionTest ( CWnd* pWnd, LBitmap*  pBitmap )
{
   LRasterPaint rstp ;
   CDC* pDC = pWnd->GetDC( ) ;

   RECT rcView ;
   PAINTXFORM PntXForm ;
   L_INT nXOffset, nYOffset ;
   HRGN hRgn ;
   RECT rcRegionRect ;

   /* Initiate the Paint toolkit */
   if ( SUCCESS != rstp.Initialize ( ) )
   {
         return FAILURE ;
   }

   PntXForm.nZoom    = m_nZoomFactor;
   PntXForm.nXOffset = m_nHscroll;
   PntXForm.nYOffset = m_nVscroll;

   /* Set the painting transformations to relfect a zoom-in by 3:1 */
   rstp.SetTransformation ( &PntXForm ) ;

   /* set the painting rectangle */
   SetRect ( &rcView, 0, 0, pBitmap->GetWidth( ), pBitmap->GetHeight( ) ) ;

   if ( m_nZoomFactor < 100 )
   {
      nXOffset = - MulDiv ( m_nHscroll, 100, m_nZoomFactor ) ;
      nYOffset = - MulDiv ( m_nVscroll, 100, m_nZoomFactor ) ;
   }
   else
   {
      nXOffset = - m_nHscroll ;
      nYOffset = - m_nVscroll ;
   }

   OffsetRect ( &rcView, nXOffset, nYOffset ) ;

   rcView.left   = MulDiv ( rcView.left,   m_nZoomFactor, 100 ) ;
   rcView.top    = MulDiv ( rcView.top,    m_nZoomFactor, 100 ) ;
   rcView.right  = MulDiv ( rcView.right,  m_nZoomFactor, 100 ) ;
   rcView.bottom = MulDiv ( rcView.bottom, m_nZoomFactor, 100 ) ;

   /* paint the bitmap */
   pBitmap->Paint()->SetDC( pDC->m_hDC );
   pBitmap->SetDstRect( &rcView );
   pBitmap->Paint()->PaintDC();

   /* Set the rectangle coordinates with respect to the DC dimensions*/
   /* Set the rectangle coordinates with respect to the DC dimensions*/
   SetRect ( &rcRegionRect, 10, 10, 110, 110 ) ;

   /* Use the current region properties and the current painting */
   /* transformations to create an ellipse region */
   rstp.RegionEllipse ( pDC->m_hDC, &rcRegionRect, &hRgn ) ;

   /* Display the resulted region */
   FrameRgn ( pDC->m_hDC, hRgn, ( HBRUSH ) GetStockObject ( BLACK_BRUSH ), 1, 1 ) ;

   /* Release the device context */
   pWnd->ReleaseDC( pDC ) ;

   pBitmap->Paint( )->SetDC(NULL);

  /* Delete the region */
   DeleteObject ( hRgn ) ;

   /* Free the paint tools handle */
   rstp.Free ( ) ;

   return SUCCESS ;
}