L_PntRegionPolygon

#include "LtPnt.h"

L_INT EXT_FUNCTION L_PntRegionPolygon(pPaint, UserDC, pptPoints, nCount, phDestRgn)

pPAINTHANDLE pPaint;

/* pointer to a paint handle */

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

pPaint

Pointer to a paint handle.

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 L_PntGetProperty. To set or change the current region properties, call L_PntSetProperty. 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 L_PntGetTransformation. To change or set the painting transformation information, call L_PntSetTransformation.

If the user has set a bitmap in the toolkit, using the function L_PntSetMetrics, 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:

L_PntSetProperty, L_PntSetTransformation, L_PntSetDCExtents, L_PntSetMetrics, L_PntDlgRegion, L_PntGetClipRgn, L_PntOffsetClipRgn, L_PntRegionBorder, L_PntRegionColor, L_PntRegionEllipse, L_PntRegionRect, L_PntRegionRoundRect, L_PntRegionScale, L_PntRegionSurface, L_PntRegionTranslate, L_PntSetClipRgn

Topics:

DigitalPaint Functions: Region Processing

 

Creating a Region

Example

L_INT g_nZoomFactor = 500;
L_INT g_nHScroll    = 0;
L_INT g_nVScroll    = 0;

L_INT RegionTest ( HWND hWnd )
{
   pPAINTHANDLE pPaint ;
   HDC          hDC ;
   POINT        ptPolyPoints [ 5 ] ;
   PAINTXFORM   PntXForm ;
   HRGN         hRgn ; 
   

   /* Initiate the Paint toolkit */
   if ( SUCCESS != L_PntInit ( &pPaint ) )
   {
      return FAILURE ; 
   }

   PntXForm.nZoom    = g_nZoomFactor ; 
   PntXForm.nXOffset = g_nHScroll ; 
   PntXForm.nYOffset = g_nVScroll ; 

   /* Set the painting transformations to relfect a zoom in by 5:1 */
   L_PntSetTransformation ( pPaint, &PntXForm ) ; 

   /* Get the device context */
   hDC = GetDC ( hWnd ) ;

   /* 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 */
   /*  trasnformations to create a polygon region */
   L_PntRegionPolygon ( pPaint, hDC, ptPolyPoints, 5, &hRgn) ;

   /* Display the resulted region */
   FrameRgn ( hDC, hRgn, ( HBRUSH ) GetStockObject ( BLACK_BRUSH ), 1, 1 ) ;
   
   /* Release the device context */
   ReleaseDC ( hWnd, hDC ) ;

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

   /* Free the paint tools handle */
   L_PntFree ( pPaint ) ;

   return SUCCESS ;
}