You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
152 lines
4.7 KiB
152 lines
4.7 KiB
/* -*- mode: C++ ; c-file-style: "stroustrup" -*- ***************************** |
|
* Qwt Widget Library |
|
* Copyright (C) 1997 Josef Wilgen |
|
* Copyright (C) 2002 Uwe Rathmann |
|
* |
|
* This library is free software; you can redistribute it and/or |
|
* modify it under the terms of the Qwt License, Version 1.0 |
|
*****************************************************************************/ |
|
|
|
#ifndef QWT_PLOT_RASTERITEM_H |
|
#define QWT_PLOT_RASTERITEM_H |
|
|
|
#include "qwt_global.h" |
|
#include "qwt_plot_item.h" |
|
#include "qwt_interval.h" |
|
#include <qglobal.h> |
|
#include <qstring.h> |
|
#include <qimage.h> |
|
|
|
/*! |
|
\brief A class, which displays raster data |
|
|
|
Raster data is a grid of pixel values, that can be represented |
|
as a QImage. It is used for many types of information like |
|
spectrograms, cartograms, geographical maps ... |
|
|
|
Often a plot has several types of raster data organized in layers. |
|
( f.e a geographical map, with weather statistics ). |
|
Using setAlpha() raster items can be stacked easily. |
|
|
|
QwtPlotRasterItem is only implemented for images of the following formats: |
|
QImage::Format_Indexed8, QImage::Format_ARGB32. |
|
|
|
\sa QwtPlotSpectrogram |
|
*/ |
|
|
|
class QWT_EXPORT QwtPlotRasterItem: public QwtPlotItem |
|
{ |
|
public: |
|
/*! |
|
\brief Cache policy |
|
The default policy is NoCache |
|
*/ |
|
enum CachePolicy |
|
{ |
|
/*! |
|
renderImage() is called each time the item has to be repainted |
|
*/ |
|
NoCache, |
|
|
|
/*! |
|
renderImage() is called, whenever the image cache is not valid, |
|
or the scales, or the size of the canvas has changed. |
|
|
|
This type of cache is useful for improving the performance |
|
of hide/show operations or manipulations of the alpha value. |
|
All other situations are handled by the canvas backing store. |
|
*/ |
|
PaintCache |
|
}; |
|
|
|
/*! |
|
Attributes to modify the drawing algorithm. |
|
\sa setPaintAttribute(), testPaintAttribute() |
|
*/ |
|
enum PaintAttribute |
|
{ |
|
/*! |
|
When the image is rendered according to the data pixels |
|
( QwtRasterData::pixelHint() ) it can be expanded to paint |
|
device resolution before it is passed to QPainter. |
|
The expansion algorithm rounds the pixel borders in the same |
|
way as the axis ticks, what is usually better than the |
|
scaling algorithm implemented in Qt. |
|
Disabling this flag might make sense, to reduce the size of a |
|
document/file. If this is possible for a document format |
|
depends on the implementation of the specific QPaintEngine. |
|
*/ |
|
|
|
PaintInDeviceResolution = 1 |
|
}; |
|
|
|
//! Paint attributes |
|
typedef QFlags<PaintAttribute> PaintAttributes; |
|
|
|
explicit QwtPlotRasterItem( const QString& title = QString::null ); |
|
explicit QwtPlotRasterItem( const QwtText& title ); |
|
virtual ~QwtPlotRasterItem(); |
|
|
|
void setPaintAttribute( PaintAttribute, bool on = true ); |
|
bool testPaintAttribute( PaintAttribute ) const; |
|
|
|
void setAlpha( int alpha ); |
|
int alpha() const; |
|
|
|
void setCachePolicy( CachePolicy ); |
|
CachePolicy cachePolicy() const; |
|
|
|
void invalidateCache(); |
|
|
|
virtual void draw( QPainter *p, |
|
const QwtScaleMap &xMap, const QwtScaleMap &yMap, |
|
const QRectF &rect ) const; |
|
|
|
virtual QRectF pixelHint( const QRectF & ) const; |
|
|
|
virtual QwtInterval interval(Qt::Axis) const; |
|
virtual QRectF boundingRect() const; |
|
|
|
protected: |
|
/*! |
|
\brief Render an image |
|
|
|
An implementation of render() might iterate over all |
|
pixels of imageRect. Each pixel has to be translated into |
|
the corresponding position in scale coordinates using the maps. |
|
This position can be used to look up a value in a implementation |
|
specific way and to map it into a color. |
|
|
|
\param xMap X-Scale Map |
|
\param yMap Y-Scale Map |
|
\param area Requested area for the image in scale coordinates |
|
\param imageSize Requested size of the image |
|
|
|
\return Rendered image |
|
*/ |
|
virtual QImage renderImage( const QwtScaleMap &xMap, |
|
const QwtScaleMap &yMap, const QRectF &area, |
|
const QSize &imageSize ) const = 0; |
|
|
|
virtual QwtScaleMap imageMap( Qt::Orientation, |
|
const QwtScaleMap &map, const QRectF &area, |
|
const QSize &imageSize, double pixelSize) const; |
|
|
|
private: |
|
QwtPlotRasterItem( const QwtPlotRasterItem & ); |
|
QwtPlotRasterItem &operator=( const QwtPlotRasterItem & ); |
|
|
|
void init(); |
|
|
|
QImage compose( const QwtScaleMap &, const QwtScaleMap &, |
|
const QRectF &imageArea, const QRectF &paintRect, |
|
const QSize &imageSize, bool doCache) const; |
|
|
|
|
|
class PrivateData; |
|
PrivateData *d_data; |
|
}; |
|
|
|
Q_DECLARE_OPERATORS_FOR_FLAGS( QwtPlotRasterItem::PaintAttributes ) |
|
|
|
#endif
|
|
|