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Diffstat (limited to 'karbon/plugins/roundcorners/roundcornersplugin.cc')
| -rw-r--r-- | karbon/plugins/roundcorners/roundcornersplugin.cc | 402 |
1 files changed, 402 insertions, 0 deletions
diff --git a/karbon/plugins/roundcorners/roundcornersplugin.cc b/karbon/plugins/roundcorners/roundcornersplugin.cc new file mode 100644 index 00000000..5a36fa51 --- /dev/null +++ b/karbon/plugins/roundcorners/roundcornersplugin.cc @@ -0,0 +1,402 @@ +/* This file is part of the KDE project + 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. +*/ + +#include "roundcornersplugin.h" +#include <karbon_view.h> +#include <karbon_part.h> +#include <core/vpath.h> +#include <core/vsegment.h> +#include <kgenericfactory.h> +#include <kdebug.h> +#include <qgroupbox.h> +#include <qlabel.h> + +#include <knuminput.h> + +typedef KGenericFactory<VRoundCornersPlugin, KarbonView> VRoundCornersPluginFactory; +K_EXPORT_COMPONENT_FACTORY( karbon_roundcornersplugin, VRoundCornersPluginFactory( "karbonroundcornersplugin" ) ) + +VRoundCornersPlugin::VRoundCornersPlugin( KarbonView *parent, const char* name, const QStringList & ) : Plugin( parent, name ) +{ + new KAction( + i18n( "&Round Corners..." ), "14_roundcorners", 0, this, + SLOT( slotRoundCorners() ), actionCollection(), "path_round_corners" ); + + m_roundCornersDlg = new VRoundCornersDlg(); + m_roundCornersDlg->setRadius( 10.0 ); +} + +VRoundCornersPlugin::~VRoundCornersPlugin() +{ +} + +void +VRoundCornersPlugin::slotRoundCorners() +{ + KarbonPart *part = ((KarbonView *)parent())->part(); + if( part && m_roundCornersDlg->exec() ) + part->addCommand( new VRoundCornersCmd( &part->document(), m_roundCornersDlg->radius() ), true ); +} + + +VRoundCornersDlg::VRoundCornersDlg( QWidget* parent, const char* name ) + : KDialogBase( parent, name, true, i18n( "Polygonize" ), Ok | Cancel ) +{ + // add input: + QGroupBox* group = new QGroupBox( 2, Qt::Horizontal, i18n( "Properties" ), this ); + + new QLabel( i18n( "Round corners:" ), group ); + m_radius = new KDoubleNumInput( group ); + group->setMinimumWidth( 300 ); + + // signals and slots: + connect( this, SIGNAL( okClicked() ), this, SLOT( accept() ) ); + connect( this, SIGNAL( cancelClicked() ), this, SLOT( reject() ) ); + + setMainWidget( group ); + setFixedSize( baseSize() ); +} + +double +VRoundCornersDlg::radius() const +{ + return m_radius->value(); +} + +void +VRoundCornersDlg::setRadius( double value ) +{ + m_radius->setValue(value); +} + + + +VRoundCornersCmd::VRoundCornersCmd( VDocument* doc, double radius ) + : VReplacingCmd( doc, i18n( "Round Corners" ) ) +{ + // Set members. + m_radius = radius > 0.0 ? radius : 1.0; +} + +void +VRoundCornersCmd::visitVSubpath( VSubpath& path ) +{ + // Optimize and avoid a crash. + if( path.isEmpty() ) + return; + + // Note: we modiy segments from path. that doesn't hurt, since we + // replace "path" with the temporary path "newPath" afterwards. + + VSubpath newPath( 0L ); + + path.first(); + // Skip "begin". + path.next(); + + /* This algorithm is worked out by <kudling AT kde DOT org> to produce similar results as + * the "round corners" algorithms found in other applications. Neither code nor + * algorithms from any 3rd party is used though. + * + * We want to replace all corners with round corners having "radius" m_radius. + * The algorithm doesn't really produce circular arcs, but that's ok since + * the algorithm achieves nice looking results and is generic enough to be applied + * to all kind of paths. + * Note also, that this algorithm doesn't touch smooth joins (in the sense of + * VSegment::isSmooth() ). + * + * We'll manipulate the input path for bookkeeping purposes and construct a new + * temporary path in parallel. We finally replace the input path with the new path. + * + * + * Without restricting generality, let's assume the input path is closed and + * contains segments which build a rectangle. + * + * 2 + * O------------O + * | | Numbers reflect the segments' order + * 3| |1 in the path. We neglect the "begin" + * | | segment here. + * O------------O + * 0 + * + * There are three unique steps to process. The second step is processed + * many times in a loop. + * + * 1) Begin + * ----- + * Split the first segment of the input path (called "path[0]" here) + * at parameter t + * + * t = path[0]->param( m_radius ) + * + * and move newPath to this new knot. If current segment is too small + * (smaller than 2 * m_radius), we always set t = 0.5 here and in the further + * steps as well. + * + * path: new path: + * + * 2 + * O------------O + * | | + * 3 | | 1 The current segment is marked with "#"s. + * | | + * O##O#########O ...O + * 0 0 + * + * 2) Loop + * ---- + * The loop step is iterated over all segments. After each appliance the index n + * is incremented and the loop step is reapplied until no untouched segment is left. + * + * Split the current segment path[n] of the input path at parameter t + * + * t = path[n]->param( path[n]->length() - m_radius ) + * + * and add the first subsegment of the curent segment to newPath. + * + * path: new path: + * + * 2 + * O------------O + * | | + * 3 | | 1 + * | | + * O--O######O##O O------O... + * 0 0 + * + * Now make the second next segment (the original path[1] segment in our example) + * the current one. Split it at parameter t + * + * t = path[n]->param( m_radius ) + * + * path: new path: + * + * 2 + * O------------O + * | # + * 3 | O 1 + * | # + * O--O------O--O O------O... + * 0 0 + * + * Make the first subsegment of the current segment the current one. + * + * path: new path: + * + * 2 + * O------------O + * | | + * 3 | O 1 O + * | # /.1 + * O--O------O--O O------O... + * 0 0 + * + * 3) End + * --- + * + * path: new path: + * + * 2 4 + * O--O------O--O 5 .O------O. 3 + * | | / \ + * 3 O O 1 6 O O 2 + * | | 7 .\ / + * O--O------O--O ...O------O. 1 + * 0 0 + */ + + double length; + double param; + + // "Begin" step. + // ============= + + // Convert flat beziers to lines. + if( path.current()->isFlat() ) + path.current()->setDegree( 1 ); + + if( path.getLast()->isFlat() ) + path.getLast()->setDegree( 1 ); + + if( + path.isClosed() && + // Don't touch smooth joins. + !path.getLast()->isSmooth( *path.current() ) ) + { + length = path.current()->length(); + + param = length > 2 * m_radius + ? path.current()->lengthParam( m_radius ) + : 0.5; + + + path.insert( + path.current()->splitAt( param ) ); + + newPath.moveTo( + path.current()->knot() ); + + path.next(); + + + if( !success() ) + setSuccess(); + } + else + { + newPath.moveTo( + path.current()->prev()->knot() ); + } + + + // "Loop" step. + // ============ + + while( + path.current() && + path.current()->next() ) + { + // Convert flat beziers to lines. + if( path.current()->isFlat() ) + path.current()->setDegree( 1 ); + + if( path.current()->next()->isFlat() ) + path.current()->next()->setDegree( 1 ); + + + // Don't touch smooth joins. + if( path.current()->isSmooth() ) + { + newPath.append( path.current()->clone() ); + path.next(); + continue; + } + + + // Split the current segment at param( m_radius ) counting + // from the end. + length = path.current()->length(); + + // If the current segment is too short to be split, just don't split it + // because it was split already a t=0.5 during the former step. + if( length > m_radius ) + { + param = path.current()->lengthParam( length - m_radius ); + + path.insert( + path.current()->splitAt( param ) ); + newPath.append( + path.current()->clone() ); + + path.next(); + } + + + // Jump to the next untouched segment. + path.next(); + + + // Split the current segment at param( m_radius ). + length = path.current()->length(); + + param = length > 2 * m_radius + ? path.current()->lengthParam( m_radius ) + : 0.5; + + path.insert( + path.current()->splitAt( param ) ); + + + // Round corner. + newPath.curveTo( + path.current()->prev()->pointAt( 0.5 ), + path.current()->pointAt( 0.5 ), + path.current()->knot() ); + + + if( !success() ) + setSuccess(); + + path.next(); + } + + + // "End" step. + // =========== + + if( path.isClosed() ) + { + // Convert flat beziers to lines. + if( path.current()->isFlat() ) + path.current()->setDegree( 1 ); + + if( path.getFirst()->next()->isFlat() ) + path.getFirst()->next()->setDegree( 1 ); + + // Don't touch smooth joins. + if( !path.current()->isSmooth( *path.getFirst()->next() ) ) + { + length = path.current()->length(); + + // If the current segment is too short to be split, just don't split it + // because it was split already at t=0.5 during the former step. + if( length > m_radius ) + { + param = path.current()->lengthParam( length - m_radius ); + + path.insert( + path.current()->splitAt( param ) ); + newPath.append( + path.current()->clone() ); + + path.next(); + } + + + path.first(); + path.next(); + + // Round corner. + newPath.curveTo( + path.getLast()->pointAt( 0.5 ), + path.current()->pointAt( 0.5 ), + path.current()->knot() ); + + + if( !success() ) + setSuccess(); + } + else + newPath.append( path.current()->clone() ); + + newPath.close(); + } + else + newPath.append( path.current()->clone() ); + + + path = newPath; + + // Invalidate bounding box once. + path.invalidateBoundingBox(); +} + +#include "roundcornersplugin.moc" + |