In This Topic ▼

LRasterPaint::SetClipRgn

Summary

Sets the current clipping region for the toolkit.

Syntax

#include "Ltwrappr.h"

L_INT LRasterPaint::SetClipRgn(hClipRgn)

Parameters

HRGN hClipRgn

A handle to the region to be used to clip the painting output. If this parameter is NULL, there is no clipping region.

Returns

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

Comments

This function creates a copy of the specified region and uses it to clip the painting output. The toolkit will use the region as it is, without doing any transformations.

If a bitmap has been set using the LRasterPaint::SetMetrics function, the toolkit will perform any necessary clipping, draw to the bitmap, and finally draw the resulting bitmap to 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

Example

L_INT LRasterPaint_SetClipRgnExample( CWnd* pWnd )  
{ 
   L_INT          nRet; 
   LRasterPaint   rstp; 
   CDC*           pDC = pWnd->GetDC() ; 
   HRGN           hClipRgn ; 
   RECT           rcShapeRect ; 
   RECT           rcDCExtents ; 
 
   /* Initiate the Paint toolkit */ 
   nRet = rstp.Initialize ( ); 
   if(nRet != SUCCESS) 
      return nRet; 
 
   /* Set the rectangle coordinates with respect to the DC dimensions*/ 
   SetRect ( &rcShapeRect, 10, 10, 110, 110 ) ; 
 
 
   /* Get the destination DC dimensions */   
   pWnd->GetClientRect ( &rcDCExtents ) ; 
 
   /* Set the toolkit user DC extents */ 
   nRet = rstp.SetDCExtents ( &rcDCExtents ) ; 
   if(nRet != SUCCESS) 
      return nRet; 
 
   /* Use the current shape properties to draw an ellipse */ 
   nRet = rstp.DrawShapeEllipse ( pDC->m_hDC, &rcShapeRect ) ; 
   if(nRet != SUCCESS) 
      return nRet; 
 
   hClipRgn = CreateRectRgn ( 120, 20, 200, 100 ) ; 
 
   /* Set painting clip region */ 
   nRet = rstp.SetClipRgn ( hClipRgn ) ; 
   if(nRet != SUCCESS) 
      return nRet; 
 
   /* Set the rectangle coordinates with respect to the DC dimensions*/ 
   SetRect ( &rcShapeRect, 110, 10, 210, 110 ) ; 
 
   /* Use the current shape properties to draw an ellipse*/ 
   nRet = rstp.DrawShapeEllipse ( pDC->m_hDC, &rcShapeRect ) ; 
   if(nRet != SUCCESS) 
      return nRet; 
 
   /* Delete the clip region */ 
   DeleteObject ( ( HRGN ) hClipRgn ) ; 
 
   /* Free the paint tools handle */ 
   nRet = rstp.Free ( ) ; 
   if(nRet != SUCCESS) 
      return nRet; 
 
   pWnd->ReleaseDC( pDC ) ; 
 
   return SUCCESS ; 
}