WELCOME TO THE PRESSURE FIELD
              ANIMATION DEMO


   This animation shows the air pressure field 
   around a sphere as the air velocity increases.


   MENU OPTIONS
   ------------

   File Menu:
       Select Quit to exit the Pressure field Demo and return to
       the IDL Demo main screen.

   View Menu:
       Select "Colors..." to launch the XLOADCT application, which
       allows you to select a different color table for the 
       animation.

   About Menu:
       Select "About this animation" for information about the 
       Pressure field  demo. 

    

   ANIMATION FEATURES
   ------------------

   BITMAP BUTTONS:

   <<PLAY BACKWARD>>
       Displays the animation frames in decreasing order.
       The animation repeats by continuing backwards.

   <<PAUSE>>
       Suspends animation until <<PLAY BACKWARD>>,
       <<PLAY FORWARD>>, or <<PLAY IN CYCLE>> is pressed.

   <<PLAY FORWARD>>
       Displays the animation frames in increasing order.
       The animation repeats by continuing from the first frame.

   <<PLAY IN CYCLE>>
       Displays the animation frames repeatedly from the first 
       frame to the last and then from the last frame back to 
       the first.

   
   OPTIONS:

   <<ANIMATION SPEED>> Slider
       Adjusts the animation speed in frames/second.

   <<ANIMATION FRAME>> Slider
       When you select <<ACTIVE SLIDER>> (see below), 
       this slider shows the index of the frame that is
       currently displayed. You can only view a 
       specific frame with the slider when animation is 
       suspended. As animation proceeds, this slider is 
       desensitized.

   <<ACTIVE SLIDER>> Checkbox
       Activates or deactivates the <<ANIMATION FRAME SLIDER>>.

   <<END ANIMATION>> Button
       Quits the application.

   <<COLORS... >> Button
       Launches the XLOADCT application so you can select a new 
       color table.

   <<HELP>> Button
       Displays information about the Pressure field demo.