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+/* This file is part of the KDE project
+ Copyright (C) 2001, The Karbon Developers
+ Copyright (C) 2002, The Karbon Developers
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Library General Public
+ License as published by the Free Software Foundation; either
+ version 2 of the License, or (at your option) any later version.
+
+ This library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public License
+ along with this library; see the file COPYING.LIB. If not, write to
+ the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+*/
+
+#ifndef __VGLOBAL_H__
+#define __VGLOBAL_H__
+
+#include <kglobal.h>
+
+// define some often used mathematical constants et al:
+
+// TODO: optimize those values.
+
+namespace VGlobal
+{
+ const double pi = 3.14159265358979323846; // pi
+ const double twopi = 6.28318530717958647692; // 2pi
+ const double pi_2 = 1.57079632679489661923; // pi/2
+ const double pi_180 = 0.01745329251994329576; // pi/180
+ const double one_pi_180 = 57.29577951308232087684; // 180/pi
+ const double sqrt2 = 1.41421356237309504880; // sqrt(2)
+ const double one_3 = 0.33333333333333333333; // 1/3
+ const double two_3 = 0.66666666666666666667; // 2/3
+ const double one_6 = 0.16666666666666666667; // 1/6
+ const double one_7 = 0.14285714285714285714; // 1/7
+
+ /**
+ * Constants used to decide if a number is equal zero or nearly the same
+ * as another number.
+ */
+ const double veryBigNumber = 1.0e8;
+ const double verySmallNumber = 1.0e-8;
+
+ /**
+ * A bezier with this flatness is considered "flat". Used in subdividing.
+ */
+ const double flatnessTolerance = 0.01;
+
+ /**
+ * A tolerance used to approximate bezier lengths. If the relative difference
+ * between chordlength and polylength (length of the controlpolygon) is smaller
+ * than this value, the length of the bezier is 1/2 chordlength + 1/2 polylength.
+ */
+ const double lengthTolerance = 0.005;
+
+ /**
+ * A tolerance used to calculate param t on a segment at a given arc
+ * length (counting from t=0).
+ * If the relative difference between a length approximation and the given
+ * length is smaller than this value, they are assumed to be identical.
+ */
+ const double paramLengthTolerance = 0.001;
+
+ /**
+ * A range for KoPoint::isNear() check, to decide if a KoPoint "is the same"
+ * as another.
+ */
+ const double isNearRange = 0.001;
+
+ /**
+ * A tolerance for multiplying normalized (length=1) vectors. A result of
+ * >= parallelTolerance indicates parallel vectors.
+ */
+ const double parallelTolerance = 0.99;
+
+ /**
+ * Returns the sign of paramater a.
+ */
+ inline int sign( double a )
+ {
+ return a < 0.0
+ ? -1
+ : 1;
+ }
+
+ /**
+ * Calculates the binomial coefficient n! / ( k! * ( n - k)! ).
+ */
+ int binomialCoeff( unsigned n, unsigned k );
+
+ /**
+ * Calculates the value ln( n! ).
+ */
+ double factorialLn( unsigned n );
+
+ /**
+ * Calculates the value ln| Gamma(x) | for x > 0.
+ */
+ double gammaLn( double x );
+}
+
+#endif
+