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L_AnnGetTransparentColor

Summary

Retrieves the transparent color set by L_AnnSetTransparentColor.

Syntax

#include "l_bitmap.h"

L_LTANN_API L_INT L_AnnGetTransparentColor(hObject, pcrTransparent)

Parameters

HANNOBJECT hObject

Handle to the annotation object.

COLORREF *pcrTransparent

Address of a COLORREF variable to be updated with the transparent color. The standard Windows values for COLORREF represent either red, green, and blue color values, or an index into the bitmap's palette. A COLORREF value with the format 0x00BBGGRR represents the blue, green, and red color values for the specified pixel, where 0xBB is the blue value, 0xGG is the green value and 0xRR is the red value. If 0x01000000 is set in the COLORREF value (0x010000ZZ), the lower 8 bits (0xZZ) represent an index into the bitmap's palette which holds the color value. These COLORREF values can be used with any Windows function and macro that takes a COLORREF parameter.

In Document and Medical toolkits, the COLORREF value may represent a 16 bit grayscale value if pBitmap is a 12 or 16-bit grayscale bitmap. So that the value is not confused with an RGB value, the COLORREF_GRAY16 mask (0x04000000) is set. In this case (0x0400YYYY), the lower 16 bits (0xYYYY) of the COLORREF value represent the 16-bit grayscale value. (0x0400FFFF is 16-bit white and 0x04000000is 16-bit black.) This is not a standard Windows value. Therefore, LEADTOOLS functions will recognize a COLORREF having this format, but Windows functions will not. For information on how to use a 16-bit grayscale COLORREF in a non-LEADTOOLS function, refer to L_GetPixelColor.

Returns

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

Comments

By default the transparent color is white (0x00FFFFFF). A transparent color is not painted when the image is painted. For information on how LEADTOOLS uses colors, refer to Using Color Values in LEADTOOLS.

The L_AnnGetTransparentColor function is valid only for the following object types when they are using a bitmap:

Point
Stamp (including the Rubber Stamp tools)

In addition, the Automation object stores transparency settings along with the other object default settings

Call the L_AnnSetTransparent function to set such objects to use a transparent color. Call the L_AnnSetTransparentColor function to set the color to be used as the transparent color. Call the L_AnnGetTransparent function to get a value that indicates whether the bitmap being used by the annotation object is using a transparent color.