GRAPH.TXT
=========

This file details the graph.c program.

It's a graph widget with some special buttons.

1. Cursors - switches 2 natty cursors on.
   Left hand one shows a small circle at data intersection
   and a small black line which is used for the "Tonic" button.

2. Tonic - shifts the section of data up or down by the amount 
   from the intersection to the left cursor black line.

3. Zero - bottoms out the curve to a "minval" for the curve.

4. Linear - linear interpolation. Where this goes you can see when
   you move the right cursor (see the *usually* diagonal line).

5. Skip - this skips the cursor pair along one cursor gap frame.
   That is, the left one goes where the right was and the right 
   shuffles along by the distance between the cursors. Why? Well,
   once you have done some "curve fixing", you usually want to
   do more starting at the last point fixed.

5. Sine + and Sine -   - do quarter sine wave interpolations.
   Plus/minus should be self explanatory - try them.

6. AV, AF and AH - these simply mark some areas based on data from 
   somewhere else.


If no cursors are on - then MOUSE_DOWN moves the widget, CLICK allows
resize.

If anyone adds extra functionality (cubic spline, etc etc) let me know
and buzz me code.

It was built for a speech synthesis system (KLATT!), hence the "funny"
dataset names F0, AV,AF,AH (a prize to the first person who knows what 
these are - not serious!)

I am,

Rob Fletcher, Computing Service, University of York, Heslington,
              YORK YO1 5DD, England.

              rpf1@tower.york.ac.uk