LRasterPaint::RegionPolygon

#include "Ltwrappr.h"

L_INT LRasterPaint::RegionPolygon(UserDC, pptPoints, nCount, phDestRgn)

HDC UserDC;	/* handle to the device context */
LPPOINT pptPoints;	/* pointer to an array of POINT structures */
L_INT nCount;	/* number of points */
pHRGN phDestRgn;	/* pointer to a region handle */

Creates a polygonal region using the specified points.

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.
pptPoints	Pointer to an array of POINT structures that specify the vertices of the polygon.
nCount	Specifies the number of vertices in the array. This value must be greater than 2.
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::RegionEllipse, LRasterPaint::RegionRect, LRasterPaint::RegionRoundRect, LRasterPaint::RegionScale, LRasterPaint::RegionSurface, LRasterPaint::RegionTranslate, LRasterPaint::SetClipRgn, Class Members

Topics:

Creating a Region

Example

L_INT LRasterPaint_RegionPolygonExample( CWnd* pWnd, L_INT m_nZoomFactor, L_INT m_nHscroll, L_INT m_nVscroll)
{
   //data member L_INT m_nZoomFactor = 500 ;
   //data member L_INT m_nHscroll    = 0 ;
   //data member L_INT m_nVscroll    = 0 ;
   L_INT          nRet;
   LRasterPaint   rstp ;
   CDC*           pDC = pWnd->GetDC( ) ;
   POINT          ptPolyPoints [ 5 ] ;
   PAINTXFORM     PntXForm ;
   HRGN           hDestRgn ; 
   /* Initiate the Paint toolkit */
   nRet = rstp.Initialize ( );
   if(nRet != SUCCESS)
      return nRet;
   PntXForm.nZoom    = m_nZoomFactor ; 
   PntXForm.nXOffset = m_nHscroll ; 
   PntXForm.nYOffset = m_nVscroll ; 
   /* Set the painting transformations to relfect a zoom in by 5:1 */
   nRet = rstp.SetTransformation (&PntXForm ) ; 
   if(nRet != SUCCESS)
      return nRet;
   /* Set the coordinates with respect to the DC dimensions*/
   ptPolyPoints [ 0 ].x = 10 ;
   ptPolyPoints [ 0 ].y = 10 ;
   ptPolyPoints [ 1 ].x = 50 ;
   ptPolyPoints [ 1 ].y = 15 ;
   ptPolyPoints [ 2 ].x = 70 ;
   ptPolyPoints [ 2 ].y = 60 ;
   ptPolyPoints [ 3 ].x = 120 ;
   ptPolyPoints [ 3 ].y = 100;
   ptPolyPoints [ 4 ].x = 20 ;
   ptPolyPoints [ 4 ].y = 80 ;
   /* Use the current region properties and the current painting 
       transformations to create a polygon region */
   nRet = rstp.RegionPolygon ( pDC->m_hDC, ptPolyPoints, 5, &hDestRgn) ;
   if(nRet != SUCCESS)
      return nRet;
   /* Display the resulted region */
   FrameRgn ( pDC->m_hDC, hDestRgn, ( HBRUSH ) GetStockObject ( BLACK_BRUSH ), 1, 1 ) ;
   /*Delete the region */
   DeleteObject ( hDestRgn ) ;
   /* Free the paint tools handle */
   nRet = rstp.Free ( ) ;
   if(nRet != SUCCESS)
      return nRet;
   pWnd->ReleaseDC( pDC ) ;
   return SUCCESS ;
}