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Use qwt to plot raster rather than my my homegrown charting stuff
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git-svn-id: http://svn.osgeo.org/qgis/trunk/qgis@14274 c8812cc2-4d05-0410-92ff-de0c093fc19c
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timlinux committed Sep 23, 2010
1 parent 30176e3 commit a918b88
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Showing 2 changed files with 57 additions and 363 deletions.
347 changes: 42 additions & 305 deletions src/app/qgsrasterlayerproperties.cpp
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Expand Up @@ -51,6 +51,12 @@
#include <QMouseEvent>
#include "qgslogger.h"

// QWT Charting widget
#include <qwt_array.h>
#include <qwt_legend.h>
#include <qwt_plot.h>
#include <qwt_plot_curve.h>
#include <qwt_plot_grid.h>

const char * const ident =
"$Id$";
Expand Down Expand Up @@ -218,8 +224,6 @@ QgsRasterLayerProperties::QgsRasterLayerProperties( QgsMapLayer* lyr, QgsMapCanv
myPixmap.fill( Qt::gray );
}
lstHistogramLabels->addItem( new QListWidgetItem( myPixmap, myRasterBandNameQString ) );
mGradientHeight = pixHistogram->height() / 2;
mGradientWidth = pixHistogram->width() / 2;
//keep a list of band names for later use
//! @note band names should not be translated!
myBandNameList.append( myRasterBandNameQString );
Expand Down Expand Up @@ -1948,8 +1952,8 @@ void QgsRasterLayerProperties::on_pbnHistRefresh_clicked()
int myXAxisMax = 0;
bool myFirstItemFlag = true;
for ( int myIteratorInt = 1;
myIteratorInt <= myBandCountInt;
++myIteratorInt )
myIteratorInt <= myBandCountInt;
++myIteratorInt )
{
QgsRasterBandStats myRasterBandStats = mRasterLayer->bandStatistics( myIteratorInt );
//calculate the x axis min max
Expand Down Expand Up @@ -1998,318 +2002,51 @@ void QgsRasterLayerProperties::on_pbnHistRefresh_clicked()
QgsDebugMsg( QString( "max %1" ).arg( myYAxisMax ) );
QgsDebugMsg( QString( "min %1" ).arg( myYAxisMin ) );

//create the image onto which graph and axes will be drawn
int myImageWidth = pixHistogram->width() - 2;
int myImageHeight = pixHistogram->height() - 2; //Take two pixels off to account for the boarder around the QLabel
QPixmap myPixmap( myImageWidth, myImageHeight );
myPixmap.fill( Qt::white );

// TODO: Confirm that removing the "const QWidget * copyAttributes" 2nd parameter,
// in order to make things work in Qt4, doesn't break things in Qt3.
//QPainter myPainter(&myPixmap, this);
QPainter myPainter( &myPixmap );
//anti alias lines in the graph
myPainter.setRenderHint( QPainter::Antialiasing );
//determine labels sizes and draw them
QFont myQFont( "arial", 8, QFont::Normal );
QFontMetrics myFontMetrics( myQFont );
myPainter.setFont( myQFont );
myPainter.setPen( Qt::black );
QString myYMaxLabel = QString::number( static_cast < unsigned int >( myYAxisMax ) );
QString myXMinLabel = QString::number( myXAxisMin );
QString myXMaxLabel = QString::number( myXAxisMax );
//calculate the gutters
int myYGutterWidth = 0;
if ( myFontMetrics.width( myXMinLabel ) < myFontMetrics.width( myYMaxLabel ) )
{
myYGutterWidth = myFontMetrics.width( myYMaxLabel ) + 2; //add 2 so we can have 1 pix whitespace either side of label
}
else
{
myYGutterWidth = myFontMetrics.width( myXMinLabel ) + 2; //add 2 so we can have 1 pix whitespace either side of label
}
int myXGutterHeight = myFontMetrics.height() + 2;
int myXGutterWidth = myFontMetrics.width( myXMaxLabel ) + 1;//1 pix whtispace from right edge of image

QwtPlot * mypPlot = new QwtPlot( mChartWidget );
//ensure all children get removed
mypPlot->setAutoDelete( true );
QVBoxLayout *mpHistogramLayout = new QVBoxLayout( mChartWidget );
mpHistogramLayout->setContentsMargins( 0, 0, 0, 0 );
mpHistogramLayout->addWidget( mypPlot );
mChartWidget->setLayout( mpHistogramLayout );
mypPlot->setTitle(QObject::tr("Raster Histogram"));
mypPlot->insertLegend(new QwtLegend(), QwtPlot::BottomLegend);
// Set axis titles
mypPlot->setAxisTitle(QwtPlot::xBottom, QObject::tr("Pixel Value"));
mypPlot->setAxisTitle(QwtPlot::yLeft, QObject::tr("Frequency"));
//
// Now calculate the graph drawable area after the axis labels have been taken
// into account
// add a grid
//
int myGraphImageWidth = myImageWidth - myYGutterWidth;
int myGraphImageHeight = myImageHeight - myXGutterHeight;

//find out how wide to draw bars when in bar chart mode
int myBarWidth = static_cast<int>(((( double )myGraphImageWidth ) / (( double )BINCOUNT ) ) );


QwtPlotGrid * myGrid = new QwtPlotGrid();
myGrid->attach(mypPlot);
//
//now draw actual graphs
//
if ( mRasterLayer->rasterType()
== QgsRasterLayer::Palette ) //paletted layers have hard coded color entries
QList<QColor> myColors;
myColors << Qt::black << Qt::red << Qt::green << Qt::blue << Qt::magenta << Qt::darkRed << Qt::darkGreen << Qt::darkBlue;
for ( int myIteratorInt = 1;
myIteratorInt <= myBandCountInt;
++myIteratorInt )
{
QPolygonF myPolygon;
QgsColorRampShader* myRasterShaderFunction = ( QgsColorRampShader* )mRasterLayer->rasterShader()->rasterShaderFunction();
QgsDebugMsg( "Making paletted image histogram....computing band stats" );
QgsDebugMsg( QString( "myLastBinWithData = %1" ).arg( myLastBinWithData ) );

QgsRasterBandStats myRasterBandStats = mRasterLayer->bandStatistics( 1 );
for ( int myBin = 0; myBin < myLastBinWithData; myBin++ )
QgsRasterBandStats myRasterBandStats = mRasterLayer->bandStatistics( myIteratorInt );
QListWidgetItem *myItem = lstHistogramLabels->item( myIteratorInt - 1 );
if ( myItem->isSelected() )
{
double myBinValue = myRasterBandStats.histogramVector->at( myBin );
QgsDebugMsg( QString( "myBin = %1 myBinValue = %2" ).arg( myBin ).arg( myBinValue ) );
//NOTE: Int division is 0 if the numerator is smaller than the denominator.
//hence the casts
int myX = static_cast<int>(((( double )myGraphImageWidth ) / (( double )myLastBinWithData ) ) * myBin );
//height varies according to freq. and scaled to greatet value in all layers
int myY = 0;
if ( myYAxisMax != 0 )
QwtPlotCurve * mypCurve = new QwtPlotCurve( tr( "Band %i" ).arg( myIteratorInt ) );
mypCurve->setRenderHint( QwtPlotItem::RenderAntialiased );
mypCurve->setPen(QPen( myColors.at( myIteratorInt ) ) );
QwtArray<double> myX2Data;//qwtarray is just a wrapped qvector
QwtArray<double> myY2Data;//qwtarray is just a wrapped qvector
for ( int myBin = 0; myBin < myLastBinWithData; myBin++ )
{
myY = static_cast<int>((( double )myBinValue / ( double )myYAxisMax ) * myGraphImageHeight );
double myBinValue = myRasterBandStats.histogramVector->at( myBin );
myX2Data.append(myBin);
myY2Data.append(myBinValue);
}

//see wehter to draw something each loop or to save up drawing for after iteration
if ( myGraphType == BAR_CHART )
{
//determine which color to draw the bar
int c1, c2, c3;
// Take middle of the interval for color
// TODO: this is not precise
double myInterval = ( myXAxisMax - myXAxisMin ) / myLastBinWithData;
double myMiddle = myXAxisMin + myBin * myInterval + myInterval / 2;

QgsDebugMsg( QString( "myMiddle = %1" ).arg( myMiddle ) );

if ( myRasterShaderFunction->shade( myMiddle, &c1, &c2, &c3 ) )
{
QgsDebugMsg( "Color not found" );
c1 = c2 = c3 = 180; // grey
}

QgsDebugMsg( QString( "c1 = %1 c2 = %2 c3 = %3" ).arg( c1 ).arg( c2 ).arg( c3 ) );

//draw the bar
//QBrush myBrush(QColor(c1,c2,c3));
myPainter.setBrush( QColor( c1, c2, c3 ) );
myPainter.setPen( QColor( c1, c2, c3 ) );
QgsDebugMsg( QString( "myX = %1 myY = %2" ).arg( myX ).arg( myY ) );
QgsDebugMsg( QString( "rect: %1, %2, %3, %4" ).arg( myX + myYGutterWidth ).arg( myImageHeight - ( myY + myXGutterHeight ) ).arg( myBarWidth ).arg( myY ) );
myPainter.drawRect( myX + myYGutterWidth, myImageHeight - ( myY + myXGutterHeight ), myBarWidth, myY );
}
//store this point in our line too
myY = myGraphImageHeight - myY;
myPolygon << QPointF( myX + myYGutterWidth, myY - myXGutterHeight );
}
//draw a line on the graph along the bar peaks;
if ( myGraphType == LINE_CHART )
{
//close of the point array so it makes a nice polygon
//bottom right point
myPolygon << QPointF(
myImageWidth,
myImageHeight - myXGutterHeight );
//bottom left point
myPolygon << QPointF(
myYGutterWidth,
myImageHeight - myXGutterHeight );
myPainter.setPen( Qt::black );
//set a gradient fill for the path
QLinearGradient myGradient = greenGradient();
myPainter.setBrush( myGradient );
QPainterPath myPath;
myPath.addPolygon( myPolygon );
myPainter.drawPath( myPath );
mypCurve->setData(myX2Data,myY2Data);
mypCurve->attach(mypPlot);
}
}
else
{

for ( int myIteratorInt = 1;
myIteratorInt <= myBandCountInt;
++myIteratorInt )
{
QgsRasterBandStats myRasterBandStats = mRasterLayer->bandStatistics( myIteratorInt );
QListWidgetItem *myItem = lstHistogramLabels->item( myIteratorInt - 1 );
if ( myItem->isSelected() )
{

QPolygonF myPolygon;
for ( int myBin = 0; myBin < myLastBinWithData; myBin++ )
{
double myBinValue = myRasterBandStats.histogramVector->at( myBin );
//NOTE: Int division is 0 if the numerator is smaller than the denominator.
//hence the casts
int myX = static_cast<int>(((( double )myGraphImageWidth ) / (( double )myLastBinWithData ) ) * myBin );
//height varies according to freq. and scaled to greatet value in all layers
int myY = static_cast<int>((( double )myBinValue / ( double )myYAxisMax ) * myGraphImageHeight );
//adjust for image origin being top left
QgsDebugMsg( "-------------" );
QgsDebugMsg( "int myY = (myBinValue/myCellCount)*myGraphImageHeight" );
QgsDebugMsg( QString( "int myY = (%1/%2)*%3" ).arg( myBinValue ).arg( myCellCount ).arg( myGraphImageHeight ) );
QgsDebugMsg( QString( "Band %1, bin %2, Hist Value : %3, Scaled Value : %4" ).arg( myIteratorInt ).arg( myBin ).arg( myBinValue ).arg( myY ) );
QgsDebugMsg( "myY = myGraphImageHeight - myY" );
QgsDebugMsg( QString( "myY = %1-%2" ).arg( myGraphImageHeight ).arg( myY ) );

if ( myGraphType == BAR_CHART )
{
//draw the bar
if ( myBandCountInt == 1 ) //draw single band images with black
{
myPainter.setPen( Qt::black );
}
else if ( myIteratorInt == 1 )
{
myPainter.setPen( Qt::red );
}
else if ( myIteratorInt == 2 )
{
myPainter.setPen( Qt::green );
}
else if ( myIteratorInt == 3 )
{
myPainter.setPen( Qt::blue );
}
else if ( myIteratorInt == 4 )
{
myPainter.setPen( Qt::magenta );
}
else if ( myIteratorInt == 5 )
{
myPainter.setPen( Qt::darkRed );
}
else if ( myIteratorInt == 6 )
{
myPainter.setPen( Qt::darkGreen );
}
else if ( myIteratorInt == 7 )
{
myPainter.setPen( Qt::darkBlue );
}
else
{
myPainter.setPen( Qt::gray );
}

// QgsDebugMsg(QString("myPainter.fillRect(QRect(%1,%2,%3,%2), myBrush );").arg(myX).arg(myY).arg(myBarWidth));

myPainter.drawRect( myX + myYGutterWidth, myImageHeight - ( myY + myXGutterHeight ), myBarWidth, myY );
}
else //line graph
{
myY = myGraphImageHeight - myY;
myPolygon << QPointF( myX + myYGutterWidth, myY );
}
}

if ( myGraphType == LINE_CHART )
{
QLinearGradient myGradient;
if ( myBandCountInt == 1 ) //draw single band images with black
{
myPainter.setPen( Qt::black );
myGradient = grayGradient();
}
else if ( myIteratorInt == 1 )
{
myPainter.setPen( Qt::red );
myGradient = redGradient();
}
else if ( myIteratorInt == 2 )
{
myPainter.setPen( Qt::green );
myGradient = greenGradient();
}
else if ( myIteratorInt == 3 )
{
myPainter.setPen( Qt::blue );
myGradient = blueGradient();
}
else if ( myIteratorInt == 4 )
{
myPainter.setPen( Qt::magenta );
myGradient = grayGradient();
}
else if ( myIteratorInt == 5 )
{
myPainter.setPen( Qt::darkRed );
myGradient = grayGradient();
}
else if ( myIteratorInt == 6 )
{
myPainter.setPen( Qt::darkGreen );
myGradient = grayGradient();
}
else if ( myIteratorInt == 7 )
{
myPainter.setPen( Qt::darkBlue );
myGradient = grayGradient();
}
else
{
myPainter.setPen( Qt::gray );
myGradient = grayGradient();
}
//close of the point array so it makes a nice polygon
//bottom right point
myPolygon << QPointF(
myImageWidth,
myImageHeight - myXGutterHeight );
//bottom left point
myPolygon << QPointF(
myYGutterWidth,
myImageHeight - myXGutterHeight );
myPainter.setPen( Qt::black );
myPainter.setBrush( myGradient );
QPainterPath myPath;
myPath.addPolygon( myPolygon );
myPainter.drawPath( myPath );
}
}
}
}

//
// Now draw interval markers on the x axis
//
int myXDivisions = myGraphImageWidth / 10;
myPainter.setPen( Qt::gray );
for ( int i = 0; i < myXDivisions; ++i )
{
QPolygon myPolygon;
myPolygon << QPoint(( i*myXDivisions ) + myYGutterWidth, myImageHeight - myXGutterHeight );
myPolygon << QPoint(( i*myXDivisions ) + myYGutterWidth, myImageHeight - ( myXGutterHeight - 5 ) );
myPolygon << QPoint(( i*myXDivisions ) + myYGutterWidth, myImageHeight - myXGutterHeight );
myPolygon << QPoint((( i + 1 )*myXDivisions ) + myYGutterWidth, myImageHeight - myXGutterHeight );
myPainter.drawPolyline( myPolygon );
}
//
// Now draw interval markers on the y axis
//
int myYDivisions = myGraphImageHeight / 10;
myPainter.setPen( Qt::gray );
for ( int i = myYDivisions; i > 0; --i )
{

QPolygon myPolygon;
int myYOrigin = myImageHeight - myXGutterHeight;
myPolygon << QPoint( myYGutterWidth, myYOrigin - ( i*myYDivisions ) );
myPolygon << QPoint( myYGutterWidth - 5, myYOrigin - ( i*myYDivisions ) );
myPolygon << QPoint( myYGutterWidth, myYOrigin - ( i*myYDivisions ) );
myPolygon << QPoint( myYGutterWidth, myYOrigin - (( i - 1 )*myYDivisions ) );
myPainter.drawPolyline( myPolygon );
}

//now draw the axis labels onto the graph
myPainter.drawText( 1, 12, myYMaxLabel );
myPainter.drawText( 1, myImageHeight - myXGutterHeight, QString::number( static_cast < unsigned int >( myYAxisMin ) ) );
myPainter.drawText( myYGutterWidth, myImageHeight - 1, myXMinLabel );
myPainter.drawText( myImageWidth - myXGutterWidth, myImageHeight - 1, myXMaxLabel );

//
// Finish up
//
myPainter.end();
pixHistogram->setPixmap( myPixmap );
QApplication::restoreOverrideCursor();
}

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