Annotation Widget

The Annotation Widget allows you to interactively annotate images and
plots with text and drawings.  You can print or save the finished
display in bitmap files (TIFF, GIFF, or PostScript).  Descriptions of
the can be saved and then reloaded later.  The Annotation Widget will
work on any IDL window or draw widget.

                    Usage

There are five basic objects: text, lines and arrows, polygons and
polylines, circles and ellipses, and rectangles.

To use the Annotation widget:

-  Select the drawing object and then create the object by clicking or
   dragging the left mouse button in the drawing window.  Experiment
   with the various options and object properties by manipulating the
   controls in the control box.
-  Release the mouse button to enter the "edit" mode, where you can
   move and resize the object by dragging the "handles".  In the 
   Polygon/Polyline mode draw straight lines by clicking the left
   mouse button at the vertices.  Draw irregularly shaped lines by
   dragging the mouse with the left button depressed.
-  Save the object by pressing the "Save" button, or by pressing the
   right mouse button when the object is properly positioned and sized.


Switch between the Draw and Edit modes by clicking the center mouse
button or by selecting the mode's push button on the control panel.

Delete the current object by switching drawing modes.


			Changing Saved Objects

Select and modify objects that have been saved by pressing the Select
button on the control panel, and then clicking the left mouse button
on the center of the object.  When the left mouse button is released
resizing handles that surround the object will appear.  This removes
the object from the saved object list and makes it the current object,
which may then be modified, moved, or deleted.  Save the object by
pressing the right mouse button or by pressing the Save button on the
control panel.


			Polygons and Polylines

The Polygon/Polyline mode has three sub-modes which are selected by a
button in the control panel:

-  Draw: (the initial mode).  Dragging or clicking the left mouse button
   adds points to the object by connecting the most recent point to the
   mouse position.
-  Edit: select and move a vertex or point by clicking and dragging
   with the left mouse button.
-  Delete: the vertex or point closest to the cursor position is removed
   when the left mouse button is pressed.

			PostScript Output

Use the Options panel to select the various types of PostScript
output: 
- Standalone or Encapsulated (to be inserted into another document).
- Monochrome or Color, always use Monochrome unless you have a color
  PostScript printer.
- Portrait or Landscape.

The width parameter scales the output size.  The height of the output
drawing is scaled from the width to retain the same aspect ratio as
the original drawing window.

There are three types of PostScript output: 

File/Export Bitmap menu - the entire window's output is
   converted to a bitmap and output as a single PostScript image.  This
   choice exactly duplicates the contents of the drawing window.

File/Write PostScript/Everything - the original window is output as a
   bitmap, and the annotation objects you created are output as
   PostScript drawing commands.  This choice provides higher resolution.

File/Write PostScript/Objects Only - only the annotation objects are
output as PostScript drawing commands.  Use this mode to combine the
annotations with some PostScript commands that you have already been
output to obtain the highest resolution.  The procedure is more
involved than the above two choices:

   1) open the PostScript device and create the plot over which you
   wish your annotations to appear.  Be sure that it has the same aspect
   ratio as does you drawing window.  For example, if you have a 640 x
   512 drawing window, and you wish to make your PostScript drawing 4
   inches wide, the PostScript height or YSIZE must be set to 4.0 * 512 /
   640 = 3.2 inches, e.g. DEVICE, XSIZE=4, YSIZE=3.2, /INCHES.

   2) select the window system as your plot device, and re-execute the
   commands that produced the background you wish to annotate.

   3) Call ANNOTATE, make your annotations, and then use this option to
   output the PostScript.  The PostScript device is not closed upon
   completion, as it is with the other two PostScript output options.



                Loading and Saving Object Lists

The descriptions of the objects you add can be saved and restored.
Use the Load, Save, and "Save As", buttons under the File button on
the main control panel.  When restoring objects, be sure that the
window you are loading into has the same geometry as did the window
from which the objects were saved.


For help on how to call ANNOTATE from your program, use the on-line
help facility and select ANNOTATE under the WIDGETLIB topic.