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L_SetBitmapRgnCurve

Summary

Creates or updates the bitmap region by adding a curved region.

Syntax

#include "l_bitmap.h"

L_LTDIS_API L_INT L_SetBitmapRgnCurve(pBitmap, pXForm, pCurve, uCombineMode)

Parameters

pBITMAPHANDLE pBitmap

Pointer to the bitmap handle referencing the bitmap where the region is to be created or updated.

pRGNXFORM pXForm

Pointer to an RGNXFORM structure that LEADTOOLS uses to translate between display coordinates and bitmap coordinates.

If you specify NULL in this parameter, the scalar fields default to 1, the offsets default to 0, and the view perspective defaults to the bitmap's view perspective.

pCURVE pCurve

Pointer to the CURVE structure that specifies the curve region. You specify the structure using device context coordinates, and LEADTOOLS translates the coordinates using the values specified in the pXForm parameter.

L_UINT uCombineMode

Flag that indicates the action to take regarding the existing bitmap region, if one is defined. For descriptions of the possible values, refer to Creating a Bitmap Region.

Returns

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

Comments

Before calling this function, declare an RGNXFORM structure and set its values, which LEADTOOLS uses to translate between device context coordinates and bitmap coordinates. For details about how the structure works refer to the RGNXFORM structure description. For a description of common usage, refer to Translating Coordinates for a Bitmap Region.

To update an existing region, specify how the new region is to be combined with the existing one, in the uCombineMode parameter. For descriptions of the possibilities, refer to Creating a Bitmap Region.

Required DLLs and Libraries

LTDIS
For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application.

Platforms

Win32, x64.

Example

This sample creates a smooth region that goes through five points, and inverts the region.

L_INT SetBitmapRgnCurveExample(pBITMAPHANDLE pBitmap) 
{ 
   L_INT nRet; 
   CURVE Curve; 
   POINT points[5]; 
 
   //Define the points of the curve 
   points[0].x = 30; 
   points[0].y = 30; 
 
   points[1].x = 30; 
   points[1].y = 200; 
 
   points[2].x = 130; 
   points[2].y = 130; 
 
   points[3].x = 75; 
   points[3].y = 75; 
 
   points[4].x = 130; 
   points[4].y = 30; 
 
   Curve.uStructSize = sizeof(CURVE); 
   Curve.nType = CURVE_STANDARD; 
   Curve.nPointCount = 5; 
   Curve.pPoints = points; 
   Curve.uFillMode = L_POLY_WINDING; 
   Curve.dTension = 0.5; 
   Curve.nClose = CURVE_CLOSE; 
   Curve.nReserved = 0; 
 
   nRet = L_SetBitmapRgnCurve(pBitmap, NULL, &Curve, L_RGN_SET); 
   if (nRet != SUCCESS) 
      return nRet; 
 
   //Do something with the region 
   nRet = L_InvertBitmap(pBitmap, 0); 
   if (nRet != SUCCESS) 
      return nRet; 
 
   //When finished, free the region 
   return L_FreeBitmapRgn(pBitmap); 
}