
Code 12 -- rectangles, circles, guitar chord grid

  parameter structure
 ___________________________________________________________
|   p1    |    p2     |    p3      |     p4    |     p5     |
|code num.| staff num.| horiz. pos.| vert. pos.| shape code |
|___12____|___________|____________|___________|____________|

 ________________________________________________
|     p6     |     p7     |    p8     |    p9    |
| horz. size | vert. size | thickness | rotation |
|____________|____________|___________|__________|

 ____________________________________________
|    p10      | p11 |    p12    |    p13     |
| arc, offset | arc | increment | chord code |
|_____________|_____|___________|____________|


P5 = 0 = rectangle,  = 1 = circle, arc,  = -1 = guitar chord grid

*


P6 = horizontal size.  If rectangle or circle, size is in scale steps.
P7 = vertical size.  If p7 = 0 then p7  = p6. (P7.ne.p6 makes ovals, etc.)

P9 = clockwise rotation in degrees.

P10 -- if a rectangle, p10 is parallelogram offest.
       if a circle, p10 = beginning point (in degrees) for start of arc.
                    p11 = end point of arc.

If a circle, p12 sets the point increment.  Normally there are 360 points.
      When p12 = some number which divides evenly in 360 an equal-sided
      polygon is created.  (e.g. p12 = 72 forms a pentagon. 360/72 = 5)

      With circles of small radius some time is saved if p12 = 2 or 3,
      thereby producing many fewer points.




*


P13 is used for setting dots on the guitar chord grid.  P13 will be a
      six-digit number of the form "abcdef" where each letter refers to a
      string.  "a" refers to the lowest string, "f" to the highest.  The
      numbers used in each of these positions will refer to a fret (up to
      the 5th fret) to be fingered.  If a number greater than 5 is used then
      an open circle will appear above the grid for that string position.

        P13 = 320106 puts dots on fret 3, string 1;  fret 2, string 2;
                     fret 1, string 4; and an open circle above string 6.



.
