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LBitmapBase::ChangeViewPerspective

#include "ltwrappr.h"

virtual L_INT LBitmapBase::ChangeViewPerspective(nViewPerspective)

virtual L_INT LBitmapBase::ChangeViewPerspective(LBitmapSrc, nViewPerspective)

L_INT nViewPerspective;	desired view perspective
LBitmapBase& LBitmapSrc;	the source bitmap object

Rotates and flips the bitmap data as necessary to achieve the desired view perspective. The ViewPerspective field in the bitmap handle is changed, and thus, the display is unchanged.

Parameter	Description
nViewPerspective	Desired view perspective. Possible values are:
	Constant	Meaning
	TOP_LEFT	[1] Top-left of image is first in memory.
	BOTTOM_LEFT180	[2] (Document/Medical only) Same as TOP_RIGHT, which is BOTTOM_LEFT rotated clockwise by 180 degrees.
	BOTTOM_LEFT	[4] Bottom-left of image is first in memory.
	TOP_LEFT180	[3] (Document/Medical only) Same as BOTTOM_RIGHT, which is TOP_LEFT rotated clockwise by 180 degrees.
	RIGHT_TOP	[6] (Document/Medical only) First row is the right side, first column is top side.
	TOP_LEFT90	[6] (Document/Medical only) Same as RIGHT_TOP, which is TOP_LEFT rotated clockwise by 90 degrees.
	LEFT_TOP	[5] (Document/Medical only) First row is the left side, first column is the top side
	BOTTOM_LEFT90	[5] (Document/Medical only) Same as LEFT_TOP, which is BOTTOM_LEFT rotated clockwise by 90 degrees
	RIGHT_BOTTOM	[7] (Document/Medical only) First row is the right side, first column is the bottom side
	BOTTOM_LEFT270	[7] (Document/Medical only) Same as RIGHT_BOTTOM, which is BOTTOM_LEFT rotated clockwise by 270 degrees
	LEFT_BOTTOM	[8] (Document/Medical only) First row is the left side, first column is top side.
	TOP_LEFT270	[8] (Document/Medical only) Same as LEFT_BOTTOM, which is TOP_LEFT rotated clockwise by 270 degrees.
LBitmapSrc	The source bitmap object.

Returns

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

Comments

Use this function to change the data and the ViewPerspective field in the bitmap handle. This function does not affect the image display. This can be used to simplify calculations that involve bitmap coordinates. For general information about view perspectives, refer to Accounting for View Perspective.

Note:

The LBitmapSrc parameter is passed by reference, and is a required parameter.

Required DLLs and Libraries

LTDIS
LTFIL

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 is the example for LBitmapBase::ChangeViewPerspective(LBitmapSrc, nViewPerspective):

L_INT LBitmapBase__ChangeViewPerspectiveExample() 
{ 
   L_INT nRet; 
   LBitmapBase MyBitmap,Bitmap2; 
 
   MyBitmap.SetFileName(MAKE_IMAGE_PATH(TEXT("image1.cmp")));  
   nRet =MyBitmap.Load(); 
   if(nRet !=SUCCESS) 
      return nRet; 
 
   if(MyBitmap.IsAllocated()) 
   { 
      nRet =Bitmap2.ChangeViewPerspective(MyBitmap, BOTTOM_LEFT); 
      if(nRet !=SUCCESS) 
         return nRet; 
   } 
 
   return SUCCESS; 
}

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Help Version 20.0.2020.4.5

LEADTOOLS Raster Imaging C++ Class Library Help

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Summary of Features

Functions:	LBitmapBase::RotateViewPerspective, LBitmapBase::GetViewPerspective, Class Members
Topics:	Accounting for View Perspective