L_BM_FOCUSEDZOOM
Send this message to zoom in or zoom out, with the ability to center the display at the current mouse position.
Parameter |
Meaning |
wParam |
Specifies whether the window should be redrawn to reflect the image changes. Use 1 to redraw the window, or 0 not to redraw it. |
lParam |
Points to the LEADBITMAPFOCUSEDZOOM structure that specifies the zoom information. |
Returns
SUCCESS |
Function was successful. |
< 0 |
An error occurred. Refer to Return Codes. |
LEADBITMAPFOCUSEDZOOM Structure
Before sending the L_BM_FOCUSEDZOOM message, your program must declare a LEADBITMAPFOCUSEDZOOM structure and update its required fields. The following table describes the fields in the structure, using MyZoom as the name of the LEADBITMAPFOCUSEDZOOM structure. )
Sample Field Name |
Data Type |
Description |
MyZoom.uStructSize |
Size of the LEADBITMAPFOCUSEDZOOM structure. This field allows for compatibility with future enhancements. It can be specified as follows: MyZoom.uStructSize = sizeof(MyZoom); | |
MyZoom.Factor |
The percentage scale factor. A value of 100 means no zooming. | |
MyZoom.Center |
TRUE for centering on the current mouse position, or FALSE for maintaining the current display offsets. | |
MyZoom.XFocus |
The horizontal mouse coordinate. | |
MyZoom.YFocus |
The vertical mouse coordinate. |