Re: Arrowlines patch version 2

[Han-Wen Nienhuys]

Op zo, 17-04-2005 te 18:26 -0300, schreef Jonatan Liljedahl:
> Here's the new version of my arrowline patch.
> 
> It lets you put arrows at the head or tail of a line.
> The arrow is rotated correctly if the line isn't straight.
> Arrow width and length is tunable.
> 
> Patch attached,

comments follow,

>+  static Stencil make_arrow (Offset &from, Offset &to, int dir, Real
length, Real width);

don't use & . If you want to modify, use * . Use const& for big
structures. In this case, just copy the arguments. 

>+    for(d=0;d<2;d++) if(dir&(1<<d)) {

what's this? If you want to do left and right, use

 Direction d = LEFT;
 do { 
   ..
 } while (flip (&d) != LEFT);
 
>+        // calculate the coordinates
>+        Real slopy = atan2(d?(y2-y1):(y1-y2),d?(x2-x1):(x1-x2));
>+        Real lcos = cos(slopy)*length, lsin = sin(slopy)*length;
>+        Real wcos = cos(slopy)*width, wsin = sin(slopy)*width;
>+        Real x=d?x1:x2, y=d?y1:y2;

can you look into using 

  angle = (to -from).arg()
  // construct horizontal arrow
  // rotate arrow
  for (int i = 0; i < points.size() ; i++)
    points[i] = points[i] * complex_exp (Offset (0, angle))

this will make the code simpler.


>+     (arrow ,integer? "Add an arrow to the line at 1: end, 2: start,
3: both.")

 
This is not done. We do not have magical number constants in lilypond. 

finally, can you reformat your code according to our standards? i.e.

  for (d = 0; d < 2; d++)
    {
      func (d, x);
    } 

notice the use of spaces and newlines around , and { } 

Can you resubmit your patch? Thanks! 

-- 
Han-Wen Nienhuys - address@hidden
LilyPond Software Design - http://www.lilypond-design.com