References ▼
#include "LtPnt.h"
L_LTPNT_API L_INT L_PntRegionPolygon(pPaint, UserDC, pptPoints, nCount, phDestRgn)
Creates a polygonal region using the specified points.
Pointer to a paint handle.
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.
Pointer to an array of POINT structures that specify the vertices of the polygon.
Specifies the number of vertices in the array. This value must be greater than 2.
Pointer to the region handle to be updated with the resulting region.
| Value | Meaning |
|---|---|
| SUCCESS | The function was successful. |
| < 1 | An error occurred. Refer to Return Codes. |
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
L_INT PntRegionPolygonExample(HWND hWnd,L_INT *g_nZoomFactor,L_INT *g_nHScroll,L_INT *g_nVScroll){L_INT nRet;pPAINTHANDLE pPaint ;HDC hDC ;POINT ptPolyPoints [ 5 ] ;PAINTXFORM PntXForm ;HRGN hRgn ;/* Initiate the Paint toolkit */nRet = L_PntInit ( &pPaint );if ( SUCCESS != nRet ){return nRet;}PntXForm.nZoom = *g_nZoomFactor ;PntXForm.nXOffset = *g_nHScroll ;PntXForm.nYOffset = *g_nVScroll ;/* Set the painting transformations to relfect a zoom in by 5:1 */nRet = L_PntSetTransformation ( pPaint, &PntXForm ) ;if(nRet != SUCCESS)return nRet;/* 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 */nRet = L_PntRegionPolygon ( pPaint, hDC, ptPolyPoints, 5, &hRgn) ;if(nRet != SUCCESS)return nRet;/* 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 ;}