LBitmapRgn::SetRgnColorRGBRange

#include "ltwrappr.h"

virtual L_INT LBitmapRgn::SetRgnColorRGBRange(crLower, crUpper)

COLORREF crLower;	/* minimum RGB color value */
COLORREF crUpper;	/* maximum RGB color value */

Creates or updates the bitmap region by adding a region that consists of all the pixels that fall in the range crLower ... crUpper, inclusively.

Parameter	Description
crLower	COLORREF value that contains the minimum (inclusive) R, G and B values. A pixel must have R, G, and B all greater than or equal to crLower and less than or equal to crUpper to be included in the region.
crUpper	COLORREF value that contains the maximum (inclusive) R,G, and B values. A pixel must have R, G, and B all greater than or equal to crLower and less than or equal to crUpper to be included in the region.

Returns

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

Comments

This function uses the RGB color model to set a region based on a color range.

To be added to the region a color must fall in the range crLower..crUpper. To set a region for all pure red, specify crLower and crUpper as follows:

crLower RGB(1,0,0)
crUpper(255,0,0)

Note that this would fail to include many colors that look red to the eye (like RGB(255,4,4)). To include ALL shades of red, you can use LBitmapRgn::SetRgnColorHSVRange.

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

This function does not support signed data images. It returns the error code ERROR_SIGNED_DATA_NOT_SUPPORTED if a signed data image is passed to this function.

This function supports 12 and 16-bit grayscale and 48 and 64-bit color images. Support for 12 and 16-bit grayscale and 48 and 64-bit color images is available only in the Document/Medical toolkits.

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.

See Also

Functions:	LBitmap::RemapHue, LBitmapRgn::SetRgnEllipse, LBitmapRgn::SetRgnPolygon, LBitmapRgn::SetRgnRect, LBitmapRgn::SetRgnRoundRect
Topics:	Raster Image Functions: Creating and Using a Region
	Working with the Existing Bitmap Region
	Saving a Region

Example

//This example sets a region corresponding to all colors that
//have an rgb that includes red but no green and no blue
L_INT SetRGBRgnExample(LBitmapRgn& rgn)
{
   COLORREF rgbLo, rgbHi;
   L_INT nRet;

   rgbLo = RGB(1,0,0);
   rgbHi = RGB(255,0,0);

   nRet = rgn.SetRgnColorRGBRange(rgbLo,rgbHi);
   return nRet;
}