* SConstruct: Further development.

[lilypond.git] / lily / bezier.cc

diff --git a/lily/bezier.cc b/lily/bezier.cc
index d4a84ef800785e74ac78b4593d8658468a2429c6..d46e63638b13816056bb49a314b7a7ea3f21954d 100644 (file)
--- a/lily/bezier.cc
+++ b/lily/bezier.cc
@@ -3,13 +3,13 @@
 
   source file of the GNU LilyPond music typesetter
 
-  (c) 1998--2001 Jan Nieuwenhuizen <janneke@gnu.org>
+  (c) 1998--2004 Jan Nieuwenhuizen <janneke@gnu.org>
 */
 
 #include <math.h>
-#include "config.h"
-#include "warn.hh"
 
+#include "config.hh"
+#include "warn.hh"
 #include "libc-extension.hh"
 #include "bezier.hh"
 #include "polynomial.hh"
@@ -30,28 +30,28 @@ binomial_coefficient (Real over , int under)
 }
 
 void
-scale (Array<Offset>* arr_p, Real x , Real y)
+scale (Array<Offset>* array, Real x , Real y)
 {
-  for (int i = 0; i < arr_p->size (); i++)
+  for (int i = 0; i < array->size (); i++)
     {
-      (*arr_p)[i][X_AXIS] = x* (*arr_p)[i][X_AXIS];
-      (*arr_p)[i][Y_AXIS] = y* (*arr_p)[i][Y_AXIS];
+      (*array)[i][X_AXIS] = x* (*array)[i][X_AXIS];
+      (*array)[i][Y_AXIS] = y* (*array)[i][Y_AXIS];
     }
 }
 
 void
-rotate (Array<Offset>* arr_p, Real phi)
+rotate (Array<Offset>* array, Real phi)
 {
   Offset rot (complex_exp (Offset (0, phi)));
-  for (int i = 0; i < arr_p->size (); i++)
-    (*arr_p)[i] = complex_multiply (rot, (*arr_p)[i]);
+  for (int i = 0; i < array->size (); i++)
+    (*array)[i] = complex_multiply (rot, (*array)[i]);
 }
 
 void
-translate (Array<Offset>* arr_p, Offset o)
+translate (Array<Offset>* array, Offset o)
 {
-  for (int i = 0; i < arr_p->size (); i++)
-    (*arr_p)[i] += o;
+  for (int i = 0; i < array->size (); i++)
+    (*array)[i] += o;
 }
 
 /*
@@ -59,6 +59,9 @@ translate (Array<Offset>* arr_p, Offset o)
   Formula of the bezier 3-spline
 
   sum_{j=0}^3 (3 over j) z_j (1-t)^ (3-j)  t^j
+
+
+  A is the axis of X coordinate.
  */
 
 Real
@@ -74,7 +77,9 @@ Bezier::get_other_coordinate (Axis a,  Real x) const
     }
   
   Offset c = curve_point (ts[0]);
-  assert (fabs (c[a] - x) < 1e-8);
+
+  if (fabs (c[a] - x) > 1e-8)
+    programming_error ("Bezier intersection not correct?");
   
   return c[other];
 }
@@ -112,10 +117,9 @@ Bezier::polynomial (Axis a)const
   Polynomial p (0.0);
   for (int j=0; j <= 3; j++)
     {
-      p += control_[j][a]
+      p += (control_[j][a] *   binomial_coefficient (3, j))
        * Polynomial::power (j , Polynomial (0,1))*
-       Polynomial::power (3 - j, Polynomial (1,-1))*
-       binomial_coefficient (3, j);
+       Polynomial::power (3 - j, Polynomial (1,-1));
     }
 
   return p;