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+/* This file is part of the KDE project
+ Copyright (C) 2002, 2003 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.
+*/
+
+#include "vflattencmd.h"
+#include <tdelocale.h>
+
+#include <core/vpath.h>
+#include <core/vsegment.h>
+
+// TODO: Think about if we want to adapt this:
+
+/*
+ * <cite from GNU ghostscript's gxpflat.c>
+ *
+ * To calculate how many points to sample along a path in order to
+ * approximate it to the desired degree of flatness, we define
+ * dist((x,y)) = abs(x) + abs(y);
+ * then the number of points we need is
+ * N = 1 + sqrt(3/4 * D / flatness),
+ * where
+ * D = max(dist(p0 - 2*p1 + p2), dist(p1 - 2*p2 + p3)).
+ * Since we are going to use a power of 2 for the number of intervals,
+ * we can avoid the square root by letting
+ * N = 1 + 2^(ceiling(log2(3/4 * D / flatness) / 2)).
+ * (Reference: DEC Paris Research Laboratory report #1, May 1989.)
+ *
+ * We treat two cases specially. First, if the curve is very
+ * short, we halve the flatness, to avoid turning short shallow curves
+ * into short straight lines. Second, if the curve forms part of a
+ * character (indicated by flatness = 0), we let
+ * N = 1 + 2 * max(abs(x3-x0), abs(y3-y0)).
+ * This is probably too conservative, but it produces good results.
+ *
+ * </cite from GNU ghostscript's gxpflat.c>
+ */
+
+
+VFlattenCmd::VFlattenCmd( VDocument *doc, double flatness )
+ : VReplacingCmd( doc, i18n( "Flatten Curves" ) )
+{
+ m_flatness = flatness > 0.0 ? flatness : 1.0;
+}
+
+void
+VFlattenCmd::visitVSubpath( VSubpath& path )
+{
+ path.first();
+
+ // Ommit first segment.
+ while( path.next() )
+ {
+ while( !path.current()->isFlat( m_flatness ) )
+ {
+ // Split at midpoint.
+ path.insert(
+ path.current()->splitAt( 0.5 ) );
+ }
+
+ // Convert to line.
+ path.current()->setDegree( 1 );
+
+ if( !success() )
+ setSuccess();
+ }
+}
+