/*
This file is part of LilyPond, the GNU music typesetter.
- Copyright (C) 1998--2012 Jan Nieuwenhuizen <janneke@gnu.org>
+ Copyright (C) 1998--2015 Jan Nieuwenhuizen <janneke@gnu.org>
LilyPond is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
}
void
-rotate (vector<Offset> *array, Real phi)
+rotate (vector<Offset> *array, Real deg)
{
- Offset rot (complex_exp (Offset (0, phi)));
+ Offset rot (offset_directed (deg));
for (vsize i = 0; i < array->size (); i++)
(*array)[i] = complex_multiply (rot, (*array)[i]);
}
return o;
}
+// The return value is normalized unless zero or indefinite.
+Offset
+Bezier::dir_at_point (Real t) const
+{
+ Offset second_order[3];
+ Offset third_order[2];
+
+ for (vsize i = 0; i < 3; i++)
+ second_order[i] = ((control_[i + 1] - control_[i]) * t) + control_[i];
+
+ for (vsize i = 0; i < 2; i++)
+ third_order[i] = ((second_order[i + 1] - second_order[i]) * t) + second_order[i];
+
+ return (third_order[1] - third_order[0]).direction ();
+}
+
/*
Cache binom (3, j) t^j (1-t)^{3-j}
*/
}
void
-Bezier::rotate (Real phi)
+Bezier::rotate (Real deg)
{
- Offset rot (complex_exp (Offset (0, phi)));
+ Offset rot (offset_directed (deg));
for (int i = 0; i < CONTROL_COUNT; i++)
control_[i] = complex_multiply (rot, control_[i]);
}