send_mouse_down_event🔗
Short description🔗
send_mouse_down_event — Send an event to a window buffer signaling a mouse down event.
Signature🔗
send_mouse_down_event( window WindowHandle, point.y Row, point.x Column, integer Button, out string Processed )
Description🔗
send_mouse_down_event sends an event
at the position (Row, Column) to the buffer window
WindowHandle, signaling that the mouse button encoded by
Button has been pressed. Please refer to get_mbutton
to see how to encode Button.
The purpose of this operator is to manipulate drawing objects in a
buffer window. If the coordinates Row and Column
are pointing on a drawing object, it is activated and can be moved
or changed by sending more events with the send_mouse_down_event
operator. To simplify the interaction with the drawing object, the
coordinates Row and Column are given in the image
coordinate system. To convert window coordinates into image
coordinates, the operator convert_coordinates_window_to_image
can be used.
If the event could be processed, send_mouse_down_event returns
'true' in Processed. If no action for the event could be
determined (e.g., because there is no drawing object below the mouse
position), 'false' is returned in Processed. In this case
the caller may determine an action for the event.
The operators send_mouse_down_event, send_mouse_up_event,
send_mouse_drag_event and send_mouse_double_click_event are
the only means to manipulate drawing objects in buffer windows.
Attention🔗
send_mouse_down_event depends on the library libcanvas, which might
not be available on embedded systems.
Execution information🔗
Execution information
-
Multithreading type: reentrant (runs in parallel with non-exclusive operators).
-
Multithreading scope: global (may be called from any thread).
-
Processed without parallelization.
Parameters🔗
WindowHandle (input_control) window → (handle)
Window handle of the buffer window.
Row (input_control) point.y → (integer / real)
Row coordinate of the mouse cursor in the image coordinate system.
Column (input_control) point.x → (integer / real)
Column coordinate of the mouse cursor in the image coordinate system.
Mouse button(s) pressed.
Processed (output_control) string → (string)
‘true’, if HALCON processed the event.
Result🔗
send_mouse_down_event returns the value 2 (H_MSG_TRUE) if the window handle
WindowHandle corresponds to a window of valid type, and the event
is properly encoded. Otherwise, an exception is raised.
Combinations with other operators🔗
Combinations
Possible predecessors
See also
send_mouse_up_event, send_mouse_double_click_event, open_window
Module🔗
Foundation