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L_SetBitmapRgnHandle

#include "l_bitmap.h"

L_LTDIS_APIL_INTL_SetBitmapRgnHandle(pBitmap, pXForm, hRgn, uCombineMode)

Creates or updates the bitmap region by adding a region that is specified by a Windows region handle.

Parameters

pBITMAPHANDLEpBitmap

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

pRGNXFORMpXForm

Pointer to anRGNXFORMstructure that LEADTOOLS uses to translate between display coordinates and bitmap coordinates.

You should create this structure when the Windows region is created. Otherwise the device context values may not be available when you are ready to add the Windows region to the bitmap region.

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.

L_UINTuCombineMode

The action to take regarding the existing bitmap region, if one is defined. For descriptions of the possible values, refer toCreating a Bitmap Region.

Returns

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

Comments

Before calling this function, you must declare anRGNXFORMstructure 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 theRGNXFORMstructure description. For a description of common usage, refer toTranslating Coordinates for a Bitmap Region.

The device coordinates are the ones that were in effect at the time the Windows region was created.

If you want to assign a region from one bitmap to another, you must use theL_GetBitmapRgnHandlefunction to get region from the first bitmap; then use the L_SetBitmapRgnHandle function to assign the region to the second bitmap.

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

Required DLLs and Libraries

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

Platforms

Win32, x64, Linux.

Functions

L_GetBitmapRgnHandle

Topics

Example

For complete sample code, refer to the DRAW
example.
This example creates and saves one elliptical region. It then creates a second
elliptical region and adds the saved region to it. Finally, it lightens the part of
the bitmap that is in the resulting region.

L_INT SetBitmapRgnHandleExample(L_HWND hWnd,pBITMAPHANDLE pBitmap){L_INT nRet;RGNXFORM XFormToBitmap; /* Structurefortransforming display coordinates */RGNXFORM XFormFromBitmap; /* Structurefortransforming bitmap coordinates */HDC hWindowDC; /* Device context of the current window */RECT rClientArea; /* Client area of the current window */RECT rRgnRect; /* Rectangle that defines the region */HRGN SavedRegion; /* Windows region handle used to save a region *//* Get the device context of the current window */hWindowDC = GetDC (hWnd);/* Get the client area of the current window */GetClientRect(hWnd,&rClientArea);/* Load a bitmap */nRet = L_LoadBitmap (MAKE_IMAGE_PATH(TEXT("ImageProcessingDemo\\Image3.cmp")), pBitmap,sizeof(BITMAPHANDLE), 0, ORDER_BGR, NULL, NULL);if(nRet != SUCCESS)returnnRet;/* Set XFormToBitmap fields, assuming that the display rectangle is the sameas the client area of the current window */XFormToBitmap.uViewPerspective = TOP_LEFT;XFormToBitmap.nXScalarNum = BITMAPWIDTH(pBitmap);XFormToBitmap.nXScalarDen = rClientArea.right;XFormToBitmap.nYScalarNum = BITMAPHEIGHT(pBitmap);XFormToBitmap.nYScalarDen = rClientArea.bottom;XFormToBitmap.nXOffset = 0;XFormToBitmap.nYOffset = 0;/* Set XFormFromBitmap fields, assuming that the display rectangle is the sameas the client area of the current window */XFormFromBitmap.uViewPerspective = TOP_LEFT;XFormFromBitmap.nXScalarNum = rClientArea.right;XFormFromBitmap.nXScalarDen = BITMAPWIDTH(pBitmap);XFormFromBitmap.nYScalarNum = rClientArea.bottom;XFormFromBitmap.nYScalarDen = BITMAPHEIGHT(pBitmap);XFormFromBitmap.nXOffset = 0;XFormFromBitmap.nYOffset = 0;/* Specify a rectangle to define the first elliptical region */SetRect(&rRgnRect, 0, rClientArea.bottom/8,rClientArea.right/4, rClientArea.bottom/2);/* Create the first elliptical region */nRet = L_SetBitmapRgnEllipse(pBitmap, &XFormToBitmap, &rRgnRect, L_RGN_SET);if(nRet != SUCCESS)returnnRet;/* Save the first elliptical region */nRet = L_GetBitmapRgnHandle(pBitmap, &XFormFromBitmap, &SavedRegion);if(nRet != SUCCESS)returnnRet;/* Free the region */L_FreeBitmapRgn(pBitmap);/* Specify a rectangle to define the second elliptical region */SetRect(&rRgnRect, rClientArea.right/4, rClientArea.bottom/8,rClientArea.right/2, rClientArea.bottom/2);/* Create the second elliptical region */nRet = L_SetBitmapRgnEllipse(pBitmap, &XFormToBitmap, &rRgnRect, L_RGN_SET);if(nRet != SUCCESS)returnnRet;/* Add the saved region to thenewone, resultinginside-by-side elliptical shapes */nRet = L_SetBitmapRgnHandle(pBitmap, &XFormToBitmap, SavedRegion, L_RGN_OR);if(nRet != SUCCESS)returnnRet;/* Lighten the region so that we will see it */nRet = L_ChangeBitmapIntensity(pBitmap,500, 0);if(nRet != SUCCESS)returnnRet;/* Delete the HRGN object */DeleteObject(SavedRegion);returnSUCCESS;}

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Help Version 21.0.2021.7.5

LEADTOOLS Raster Imaging C API Help

Introduction

Version History

Getting Started

Files To Be Included With Your Application

文档Writers – Files To Be Included With Your Application

LEADTOOLS Raster Imaging Features

Quick Reference

Tutorials

Function References

Callback Functions

Summary of Features

Appendix