Draws a polygon using the specified points.
#include "LtPnt.h"
L_LTPNT_API L_INT L_PntDrawShapePolygon(pPaint, UserDC, pptPoints, nCount)
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.
Value | Meaning |
---|---|
SUCCESS | The function was successful. |
< 1 | An error occurred. Refer to Return Codes. |
The polygon is closed automatically by drawing a line from the last vertex to the first.
The polygon will be drawn using the current shape properties. To determine the current shape properties, call L_PntGetProperty. To set or change the current shape properties, call L_PntSetProperty. For more information on the shape properties, refer to the PAINTSHAPE structure.
If UserDC is not NULL, the toolkit will paint the polygon on the specified device context. If UserDC is NULL, the polygon will not be painted on a device context.
If the UserDC is not NULL, the user should set the DC boundaries before calling this function, by calling L_PntSetDCExtents.
If a bitmap has been set using the L_PntSetMetrics function, the polygon will be drawn on the specified bitmap. If UserDC is not NULL and a bitmap has been set using the L_PntSetMetrics function, then the polygon will be drawn to both the device context and the bitmap.
L_INT PntDrawShapePolygonExample(HWND hWnd)
{
L_INT nRet;
pPAINTHANDLE pPaint ;
HDC hDC ;
PAINTSHAPE shape ;
POINT ptPolyPoints [ 5 ] ;
/* Initiate the Paint toolkit */
nRet = L_PntInit ( &pPaint );
if ( SUCCESS != nRet )
{
return nRet;
}
/* Get device context to draw on */
hDC = GetDC ( hWnd ) ;
/* Get the current shape properties */
nRet = L_PntGetProperty ( pPaint, PAINT_GROUP_SHAPE, &shape ) ;
if(nRet != SUCCESS)
return nRet;
/* Set the required shape properties */
shape.nSize = sizeof ( PAINTSHAPE ) ;
shape.dwMask = PSF_BORDERWIDTH |
PSF_BORDERCOLOR |
PSF_BACKGROUNDCOLOR;
shape.nBorderWidth = 2 ;
shape.crBorderColor = RGB ( 255, 0, 0 ) ;
shape.crBackgroundColor = RGB ( 255, 255, 192 ) ;
/* Set the new shape properties */
nRet = L_PntSetProperty ( pPaint, PAINT_GROUP_SHAPE, &shape ) ;
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 = 100 ;
ptPolyPoints [ 2 ].y = 160 ;
ptPolyPoints [ 3 ].x = 100 ;
ptPolyPoints [ 3 ].y = 100;
ptPolyPoints [ 4 ].x = 20 ;
ptPolyPoints [ 4 ].y = 60 ;
/* Use the current shape properties to draw a polygon to the DC (hDC) */
nRet = L_PntDrawShapePolygon ( pPaint, hDC, ptPolyPoints, 5 ) ;
if(nRet != SUCCESS)
return nRet;
/* Release the device context */
ReleaseDC ( hWnd, hDC ) ;
/* Free the paint tools handle */
L_PntFree ( pPaint ) ;
return SUCCESS ;
}