LAnnPolygon::Define

#include "ltwrappr.h"

virtual L_INT LAnnPolygon::Define(pPoint, uState)

LPPOINT pPoint;

/* pointer to a POINT structure */

L_UINT uState;

/* state of the process */

 

NOTE:

THIS FUNCTION IS NOW INHERITED DIRECTLY FROM THE PARENT LANNOTATION CLASS.

Specifies the shape when creating or transforming an annotation object. This function specifies one point in the current window each time it is called.

Parameter

Description

pPoint

Pointer to a POINT structure. The points in the array must be in the order in which the vertices are connected. To define the line that closes a polygon, the last point in the array is connected to the first point of the array. To define a rectangle, the last point is the opposite vertex of the first point.

uState

State of the process of modifying the annotation object. Possible values are:

 

Value

Meaning

 

ANNDEFINE_BEGINSET

[0] This is the first point to define a new object.

 

ANNDEFINE_BEGINMOVE

[1] This is the point from which to move the object.

 

ANNDEFINE_BEGINROTATE

[2] This is the starting point for calculating the angle of rotation.

 

ANNDEFINE_BEGINRESIZE

[3] This is the starting point for calculating the how to resize the object.

 

ANNDEFINE_BEGINSELECT

[4] This is the first corner of the rectangle used to select objects.

 

ANNDEFINE_APPEND

[5] This is the next point when defining an object that requires more than two points.

 

ANNDEFINE_UPDATE

[6] This is the current mouse position during creation of the object. Use this on a mouse move event to reflect the current shape of the object.

 

ANNDEFINE_END

[7] This is the last point.

 

ANNDEFINE_BEGINMOVESELECTED

[8] This is the point from which to move all selected objects.

 

ANNDEFINE_BEGINROTATESELECTED

[9] This is the starting point for calculating the angle of rotation for all selected objects.

 

ANNDEFINE_BEGINRESIZESELECTED

[10] This is the starting point for calculating the how to resize all selected objects.

Returns

SUCCESS

The function was successful.

< 1

An error occurred. Refer to Return Codes.

Comments

Before calling this function, you must create the object, and the object must have a window handle (which can be inherited from the container).

To specify the shape of an object that is defined by a polygon, you call this function repeatedly to create an array of points, which must be in the order in which the vertices are connected. To define the line that closes a polygon, the last point in the array is connected to the first point of the array.

You can also call this function on mouse move events during the definition of an object to update the current view of the object being defined. Thus, this function can handle the display of the object during and after its creation.

When rotating or resizing an object, you call this function for the first point and last point, and this function determines the angle of rotation or resize parameters based on the difference in the points.

Required DLLs and Libraries

LTANN

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:

Class Members

Topics:

Annotation Functions: Creating and Deleting Annotations

 

Implementing Annotations

 

Types of Annotations

 

Displaying and Manipulating Annotation Objects

Example

L_INT LAnnPolygon_DefineExample(LAnnPolygon  * pAnnObject,HWND hWnd)
{
	L_INT nRet;
   RECT   rClientRect;
   POINT  MyPoint;
   GetClientRect(hWnd,&rClientRect) ;
   // Set the point for the opposite corner of the rectangle
   MyPoint.x = rClientRect.right / 2;
   MyPoint.y = rClientRect.bottom / 2;
   
   // Finish defining the rectangular annotation object 
   nRet = pAnnObject->Define( &MyPoint, ANNDEFINE_END);
	return nRet;
}