qgsuniquevaluerenderer.cpp

一个非常好的GIS开源新版本

/***************************************************************************
                         qgsuniquevaluerenderer.cpp  -  description
                             -------------------
    begin                : July 2004
    copyright            : (C) 2004 by Marco Hugentobler
    email                : [e-mail]
 ***************************************************************************/

/***************************************************************************
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 ***************************************************************************/
/* $Id: qgsuniquevaluerenderer.cpp 5371 2006-04-25 01:52:13Z wonder $ */

#include "qgsuniquevaluerenderer.h"
#include "qgsfeature.h"
#include "qgsvectorlayer.h"
#include "qgssymbol.h"
#include "qgssymbologyutils.h"
#include "qgslogger.h"
#include <math.h>
#include <QDomNode>
#include <QPainter>
#include <QImage>
#include <vector>

QgsUniqueValueRenderer::QgsUniqueValueRenderer(QGis::VectorType type): mClassificationField(0)
{
  mVectorType = type;
  mSymbolAttributesDirty = false;
}

QgsUniqueValueRenderer::QgsUniqueValueRenderer(const QgsUniqueValueRenderer& other)
{
  mVectorType = other.mVectorType;
  mClassificationField = other.mClassificationField;
  QMap<QString, QgsSymbol*> s = other.mSymbols;
  for(QMap<QString, QgsSymbol*>::iterator it=s.begin(); it!=s.end(); ++it)
  {
    QgsSymbol* s = new QgsSymbol(* it.value());
    insertValue(it.key(), s);
  }
  updateSymbolAttributes();
}

QgsUniqueValueRenderer& QgsUniqueValueRenderer::operator=(const QgsUniqueValueRenderer& other)
{
  if(this != &other)
  {
    mVectorType = other.mVectorType;
    mClassificationField = other.mClassificationField;
    clearValues();
    for(QMap<QString, QgsSymbol*>::iterator it=mSymbols.begin(); it!=mSymbols.end(); ++it)
    {
      QgsSymbol* s = new QgsSymbol(*it.value());
      insertValue(it.key(), s);
    }
    updateSymbolAttributes();
  }
  return *this;
}

QgsUniqueValueRenderer::~QgsUniqueValueRenderer()
{
  for(QMap<QString,QgsSymbol*>::iterator it=mSymbols.begin();it!=mSymbols.end();++it)
  {
    delete it.value();
  }
}

const QList<QgsSymbol*> QgsUniqueValueRenderer::symbols() const
{
  QList <QgsSymbol*> symbollist;
  for(QMap<QString, QgsSymbol*>::const_iterator it = mSymbols.begin(); it!=mSymbols.end(); ++it)
  {
    symbollist.append(it.value());
  }
  return symbollist;
}

void QgsUniqueValueRenderer::insertValue(QString name, QgsSymbol* symbol)
{
  mSymbols.insert(name, symbol);
  mSymbolAttributesDirty=true;
}

void QgsUniqueValueRenderer::setClassificationField(int field)
{
  mClassificationField=field;
}

int QgsUniqueValueRenderer::classificationField() const
{
  return mClassificationField;
}

bool QgsUniqueValueRenderer::willRenderFeature(QgsFeature *f)
{
  return (symbolForFeature(f) != 0);
}
    
void QgsUniqueValueRenderer::renderFeature(QPainter* p, QgsFeature& f,QImage* img, 
	double* scalefactor, bool selected, double widthScale)
{
  if(mSymbolAttributesDirty) {
    QgsDebugMsg("Missed updateSymbolAttributes() call - doing it now");
    updateSymbolAttributes();
  }
    
  QgsSymbol* symbol = symbolForFeature(&f);
  if(!symbol) //no matching symbol
  {
    if ( img && mVectorType == QGis::Point )
    {
      img->fill(0);
    }
    else if ( mVectorType != QGis::Point )
    {
      p->setPen(Qt::NoPen);
      p->setBrush(Qt::NoBrush);
    }
    return;
  }

  // Point 
  if ( img && mVectorType == QGis::Point ) 
  {
    double fieldScale = 1.0;
    double rotation = 0.0;

    if ( symbol->scaleClassificationField() >= 0)
    {
      //first find out the value for the scale classification attribute
      const QgsAttributeMap& attrs = f.attributeMap();
      fieldScale = sqrt(fabs(attrs[symbol->scaleClassificationField()].toDouble()));
      QgsDebugMsgLevel(QString("Feature has field scale factor %1").arg(fieldScale), 3);
    }
    if ( symbol->rotationClassificationField() >= 0 )
    {
      const QgsAttributeMap& attrs = f.attributeMap();
      rotation = attrs[symbol->rotationClassificationField()].toDouble();
      QgsDebugMsgLevel(QString("Feature has rotation factor %1").arg(rotation), 3);
    }
    *img = symbol->getPointSymbolAsImage( widthScale, selected, mSelectionColor,
      *scalefactor * fieldScale, rotation);
  }  
  // Line, polygon
  else if ( mVectorType != QGis::Point )
  {
    if( !selected ) 
    {
      QPen pen=symbol->pen();
      pen.setWidthF ( widthScale * pen.width() );
      p->setPen(pen);
      p->setBrush(symbol->brush());
    }
    else
    {
      QPen pen=symbol->pen();
      pen.setWidthF ( widthScale * pen.width() );
      pen.setColor(mSelectionColor);
      QBrush brush=symbol->brush();
      brush.setColor(mSelectionColor);
      p->setPen(pen);
      p->setBrush(brush);
    }
  }
}

QgsSymbol* QgsUniqueValueRenderer::symbolForFeature(const QgsFeature* f)
{
  //first find out the value
  const QgsAttributeMap& attrs = f->attributeMap();
  QString value = attrs[mClassificationField].toString();

  QMap<QString,QgsSymbol*>::iterator it=mSymbols.find(value);
  if(it == mSymbols.end())
  {
    return 0;
  }
  else
  {
    return it.value();
  }
}

void QgsUniqueValueRenderer::readXML(const QDomNode& rnode, QgsVectorLayer& vl)
{
  mVectorType = vl.vectorType();
  QDomNode classnode = rnode.namedItem("classificationfield");
  int classificationfield = classnode.toElement().text().toInt();
  this->setClassificationField(classificationfield);

  QDomNode symbolnode = rnode.namedItem("symbol");
  while (!symbolnode.isNull())
  {
    QgsSymbol* msy = new QgsSymbol(mVectorType);
    msy->readXML ( symbolnode );
    insertValue(msy->lowerValue(),msy);
    symbolnode = symbolnode.nextSibling();
  }
  updateSymbolAttributes();
  vl.setRenderer(this);
}

void QgsUniqueValueRenderer::clearValues()
{
  for(QMap<QString,QgsSymbol*>::iterator it=mSymbols.begin();it!=mSymbols.end();++it)
  {
    delete it.value();
  }
  mSymbols.clear();
  updateSymbolAttributes();
}

void QgsUniqueValueRenderer::updateSymbolAttributes()
{
  mSymbolAttributesDirty = false;

  mSymbolAttributes.clear();

  QMap<QString, QgsSymbol*>::iterator it;
  for (it = mSymbols.begin(); it != mSymbols.end(); ++it)
  {
    int rotationField = (*it)->rotationClassificationField();
    if ( rotationField >= 0 && !(mSymbolAttributes.contains(rotationField)) )
    {
      mSymbolAttributes.append(rotationField);
    }
    int scaleField = (*it)->scaleClassificationField(); 
    if ( scaleField >= 0 && !(mSymbolAttributes.contains(scaleField)) )
    {
      mSymbolAttributes.append(scaleField);
    }
  }
}

QString QgsUniqueValueRenderer::name() const
{
    return "Unique Value";
}

QgsAttributeList QgsUniqueValueRenderer::classificationAttributes() const
{
  QgsAttributeList list(mSymbolAttributes);
  if ( ! list.contains(mClassificationField) )
  {
    list.append(mClassificationField);
  }
  return list;
}

bool QgsUniqueValueRenderer::writeXML( QDomNode & layer_node, QDomDocument & document ) const
{
  bool returnval=true;
  QDomElement uniquevalue=document.createElement("uniquevalue");
  layer_node.appendChild(uniquevalue);
  QDomElement classificationfield=document.createElement("classificationfield");
  QDomText classificationfieldtxt=document.createTextNode(QString::number(mClassificationField));
  classificationfield.appendChild(classificationfieldtxt);
  uniquevalue.appendChild(classificationfield);
  for(QMap<QString,QgsSymbol*>::const_iterator it=mSymbols.begin();it!=mSymbols.end();++it)
  {
    if(!(it.value()->writeXML(uniquevalue,document)))
    {
      returnval=false;  
    }
  }
  return returnval;
}

QgsRenderer* QgsUniqueValueRenderer::clone() const
{
  QgsUniqueValueRenderer* r = new QgsUniqueValueRenderer(*this);
  return r;
}