draw_point — Draw a point.
draw_point returns the parameter for a point, which has been
created interactively by the user in the window.
To create a point you have to press the left mouse button. While keeping
the button pressed you may “drag” the point in any direction.
Pressing the right mouse button terminates the procedure. On macOS
draw_point can also be terminated by pressing the escape key.
After terminating the procedure the point is not visible in the window any longer.
If used in a buffer window, mouse events have to be supplied by the application, while the draw operator must be run in another thread.
Row index of the point.
Column index of the point.
draw_point(WindowHandle,Row,Column) gen_cross_contour_xld (Cross, Row, Column, 6, 0)
draw_point returns 2 (H_MSG_TRUE), if the window is valid and the
needed drawing mode is available.
If necessary, an exception is raised.