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diff --git a/doc/html/showimg-example.html b/doc/html/showimg-example.html new file mode 100644 index 0000000..ae6fe8d --- /dev/null +++ b/doc/html/showimg-example.html @@ -0,0 +1,883 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> +<!-- /home/espenr/tmp/qt-3.3.8-espenr-2499/qt-x11-free-3.3.8/examples/showimg/showimg.doc:4 --> +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> +<title>Show Image</title> +<style type="text/css"><!-- +fn { margin-left: 1cm; text-indent: -1cm; } +a:link { color: #004faf; text-decoration: none } +a:visited { color: #672967; text-decoration: none } +body { background: #ffffff; color: black; } +--></style> +</head> +<body> + +<table border="0" cellpadding="0" cellspacing="0" width="100%"> +<tr bgcolor="#E5E5E5"> +<td valign=center> + <a href="index.html"> +<font color="#004faf">Home</font></a> + | <a href="classes.html"> +<font color="#004faf">All Classes</font></a> + | <a href="mainclasses.html"> +<font color="#004faf">Main Classes</font></a> + | <a href="annotated.html"> +<font color="#004faf">Annotated</font></a> + | <a href="groups.html"> +<font color="#004faf">Grouped Classes</font></a> + | <a href="functions.html"> +<font color="#004faf">Functions</font></a> +</td> +<td align="right" valign="center"><img src="logo32.png" align="right" width="64" height="32" border="0"></td></tr></table><h1 align=center>Show Image</h1> + + +<p> +This example reads and displays an image in any supported image +format (GIF, BMP, PPM, XMP, etc.). +<p> <hr> +<p> Header file: +<p> <pre>/**************************************************************************** +** $Id: qt/showimg.h 3.3.8 edited Jan 11 14:37 $ +** +** Copyright (C) 1992-2007 Trolltech ASA. All rights reserved. +** +** This file is part of an example program for Qt. This example +** program may be used, distributed and modified without limitation. +** +*****************************************************************************/ + +#ifndef SHOWIMG_H +#define SHOWIMG_H + +#include <<a href="qwidget-h.html">qwidget.h</a>> +#include <<a href="qimage-h.html">qimage.h</a>> + + +class QLabel; +class QMenuBar; +class QPopupMenu; + +class ImageViewer : public <a href="qwidget.html">QWidget</a> +{ + <a href="metaobjects.html#Q_OBJECT">Q_OBJECT</a> +public: + ImageViewer( <a href="qwidget.html">QWidget</a> *parent=0, const char *name=0, int wFlags=0 ); + ~ImageViewer(); + bool loadImage( const <a href="qstring.html">QString</a>& ); +protected: + void paintEvent( <a href="qpaintevent.html">QPaintEvent</a> * ); + void resizeEvent( <a href="qresizeevent.html">QResizeEvent</a> * ); + void mousePressEvent( <a href="qmouseevent.html">QMouseEvent</a> * ); + void mouseReleaseEvent( <a href="qmouseevent.html">QMouseEvent</a> * ); + void mouseMoveEvent( <a href="qmouseevent.html">QMouseEvent</a> * ); + +private: + void scale(); + int conversion_flags; + bool smooth() const; + bool useColorContext() const; + int alloc_context; + bool convertEvent( <a href="qmouseevent.html">QMouseEvent</a>* e, int& x, int& y ); + <a href="qstring.html">QString</a> filename; + <a href="qimage.html">QImage</a> image; // the loaded image + <a href="qpixmap.html">QPixmap</a> pm; // the converted pixmap + <a href="qpixmap.html">QPixmap</a> pmScaled; // the scaled pixmap + + <a href="qmenubar.html">QMenuBar</a> *menubar; + <a href="qpopupmenu.html">QPopupMenu</a> *file; + <a href="qpopupmenu.html">QPopupMenu</a> *saveimage; + <a href="qpopupmenu.html">QPopupMenu</a> *savepixmap; + <a href="qpopupmenu.html">QPopupMenu</a> *edit; + <a href="qpopupmenu.html">QPopupMenu</a> *options; + + <a href="qwidget.html">QWidget</a> *helpmsg; + <a href="qlabel.html">QLabel</a> *status; + int si, sp, ac, co, mo, fd, bd, // Menu item ids + td, ta, ba, fa, au, ad, dd, + ss, cc, t1, t8, t32; + void updateStatus(); + void setMenuItemFlags(); + bool reconvertImage(); + int pickx, picky; + int clickx, clicky; + bool may_be_other; + static ImageViewer* other; + void setImage(const <a href="qimage.html">QImage</a>& newimage); + +private slots: + void to1Bit(); + void to8Bit(); + void to32Bit(); + void toBitDepth(int); + + void copy(); + void paste(); + + void hFlip(); + void vFlip(); + void rot180(); + + void editText(); + + void newWindow(); + void openFile(); + void saveImage(int); + void savePixmap(int); + void giveHelp(); + void doOption(int); + void copyFrom(ImageViewer*); +}; + + +#endif // SHOWIMG_H +</pre> + +<p> <hr> +<p> Implementation: +<p> <pre>/**************************************************************************** +** $Id: qt/showimg.cpp 3.3.8 edited Jan 11 14:37 $ +** +** Copyright (C) 1992-2007 Trolltech ASA. All rights reserved. +** +** This file is part of an example program for Qt. This example +** program may be used, distributed and modified without limitation. +** +*****************************************************************************/ + +#include "showimg.h" +#include "imagetexteditor.h" +#include <<a href="qmenubar-h.html">qmenubar.h</a>> +#include <<a href="qfiledialog-h.html">qfiledialog.h</a>> +#include <<a href="qmessagebox-h.html">qmessagebox.h</a>> +#include <<a href="qpopupmenu-h.html">qpopupmenu.h</a>> +#include <<a href="qlabel-h.html">qlabel.h</a>> +#include <<a href="qpainter-h.html">qpainter.h</a>> +#include <<a href="qapplication-h.html">qapplication.h</a>> +#include <<a href="qclipboard-h.html">qclipboard.h</a>> + + +/* + In the constructor, we just pass the standard parameters on to + QWidget. + + The menu uses a single slot to simplify the process of adding + more items to the options menu. +*/ +<a name="f405"></a>ImageViewer::ImageViewer( <a href="qwidget.html">QWidget</a> *parent, const char *name, int wFlags ) + : <a href="qwidget.html">QWidget</a>( parent, name, wFlags ), + conversion_flags( PreferDither ), + helpmsg( 0 ) +{ + pickx = -1; + picky = -1; + clickx = -1; + clicky = -1; + alloc_context = 0; + + menubar = new <a href="qmenubar.html">QMenuBar</a>(this); +<a name="x1326"></a> menubar-><a href="qmenubar.html#setSeparator">setSeparator</a>( QMenuBar::InWindowsStyle ); + +<a name="x1323"></a> <a href="qstrlist.html">QStrList</a> fmt = QImage::<a href="qimage.html#outputFormats">outputFormats</a>(); + saveimage = new <a href="qpopupmenu.html">QPopupMenu</a>( menubar ); + savepixmap = new <a href="qpopupmenu.html">QPopupMenu</a>( menubar ); +<a name="x1344"></a><a name="x1343"></a> for (const char* f = fmt.<a href="qptrlist.html#first">first</a>(); f; f = fmt.<a href="qptrlist.html#next">next</a>()) { +<a name="x1327"></a> saveimage-><a href="qmenudata.html#insertItem">insertItem</a>( f ); + savepixmap-><a href="qmenudata.html#insertItem">insertItem</a>( f ); + } +<a name="x1341"></a> <a href="qobject.html#connect">connect</a>( saveimage, SIGNAL(<a href="qpopupmenu.html#activated">activated</a>(int)), this, SLOT(saveImage(int)) ); + <a href="qobject.html#connect">connect</a>( savepixmap, SIGNAL(<a href="qpopupmenu.html#activated">activated</a>(int)), this, SLOT(savePixmap(int)) ); + + file = new <a href="qpopupmenu.html">QPopupMenu</a>( menubar ); + menubar-><a href="qmenudata.html#insertItem">insertItem</a>( "&File", file ); + file-><a href="qmenudata.html#insertItem">insertItem</a>( "&New window", this, SLOT(newWindow()), CTRL+Key_N ); + file-><a href="qmenudata.html#insertItem">insertItem</a>( "&Open...", this, SLOT(openFile()), CTRL+Key_O ); + si = file-><a href="qmenudata.html#insertItem">insertItem</a>( "Save image", saveimage ); + sp = file-><a href="qmenudata.html#insertItem">insertItem</a>( "Save pixmap", savepixmap ); +<a name="x1328"></a> file-><a href="qmenudata.html#insertSeparator">insertSeparator</a>(); + file-><a href="qmenudata.html#insertItem">insertItem</a>( "E&xit", qApp, SLOT(<a href="qapplication.html#quit">quit</a>()), CTRL+Key_Q ); + + edit = new <a href="qpopupmenu.html">QPopupMenu</a>( menubar ); + menubar-><a href="qmenudata.html#insertItem">insertItem</a>( "&Edit", edit ); + edit-><a href="qmenudata.html#insertItem">insertItem</a>("&Copy", this, SLOT(copy()), CTRL+Key_C); + edit-><a href="qmenudata.html#insertItem">insertItem</a>("&Paste", this, SLOT(paste()), CTRL+Key_V); + edit-><a href="qmenudata.html#insertSeparator">insertSeparator</a>(); + edit-><a href="qmenudata.html#insertItem">insertItem</a>("&Horizontal flip", this, SLOT(hFlip()), ALT+Key_H); + edit-><a href="qmenudata.html#insertItem">insertItem</a>("&Vertical flip", this, SLOT(vFlip()), ALT+Key_V); + edit-><a href="qmenudata.html#insertItem">insertItem</a>("&Rotate 180", this, SLOT(rot180()), ALT+Key_R); + edit-><a href="qmenudata.html#insertSeparator">insertSeparator</a>(); + edit-><a href="qmenudata.html#insertItem">insertItem</a>("&Text...", this, SLOT(editText())); + edit-><a href="qmenudata.html#insertSeparator">insertSeparator</a>(); + t1 = edit-><a href="qmenudata.html#insertItem">insertItem</a>( "Convert to &1 bit", this, SLOT(to1Bit()) ); + t8 = edit-><a href="qmenudata.html#insertItem">insertItem</a>( "Convert to &8 bit", this, SLOT(to8Bit()) ); + t32 = edit-><a href="qmenudata.html#insertItem">insertItem</a>( "Convert to &32 bit", this, SLOT(to32Bit()) ); + + options = new <a href="qpopupmenu.html">QPopupMenu</a>( menubar ); + menubar-><a href="qmenudata.html#insertItem">insertItem</a>( "&Options", options ); + ac = options-><a href="qmenudata.html#insertItem">insertItem</a>( "AutoColor" ); + co = options-><a href="qmenudata.html#insertItem">insertItem</a>( "ColorOnly" ); + mo = options-><a href="qmenudata.html#insertItem">insertItem</a>( "MonoOnly" ); + options-><a href="qmenudata.html#insertSeparator">insertSeparator</a>(); + fd = options-><a href="qmenudata.html#insertItem">insertItem</a>( "DiffuseDither" ); + bd = options-><a href="qmenudata.html#insertItem">insertItem</a>( "OrderedDither" ); + td = options-><a href="qmenudata.html#insertItem">insertItem</a>( "ThresholdDither" ); + options-><a href="qmenudata.html#insertSeparator">insertSeparator</a>(); + ta = options-><a href="qmenudata.html#insertItem">insertItem</a>( "ThresholdAlphaDither" ); + ba = options-><a href="qmenudata.html#insertItem">insertItem</a>( "OrderedAlphaDither" ); + fa = options-><a href="qmenudata.html#insertItem">insertItem</a>( "DiffuseAlphaDither" ); + options-><a href="qmenudata.html#insertSeparator">insertSeparator</a>(); + ad = options-><a href="qmenudata.html#insertItem">insertItem</a>( "PreferDither" ); + dd = options-><a href="qmenudata.html#insertItem">insertItem</a>( "AvoidDither" ); + options-><a href="qmenudata.html#insertSeparator">insertSeparator</a>(); + ss = options-><a href="qmenudata.html#insertItem">insertItem</a>( "Smooth scaling" ); + cc = options-><a href="qmenudata.html#insertItem">insertItem</a>( "Use color context" ); +<a name="x1309"></a> if ( QApplication::<a href="qapplication.html#colorSpec">colorSpec</a>() == QApplication::ManyColor ) +<a name="x1331"></a> options-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( cc, FALSE ); +<a name="x1342"></a> options-><a href="qpopupmenu.html#setCheckable">setCheckable</a>( TRUE ); + setMenuItemFlags(); + + menubar-><a href="qmenudata.html#insertSeparator">insertSeparator</a>(); + + <a href="qpopupmenu.html">QPopupMenu</a>* help = new <a href="qpopupmenu.html">QPopupMenu</a>( menubar ); + menubar-><a href="qmenudata.html#insertItem">insertItem</a>( "&Help", help ); + help-><a href="qmenudata.html#insertItem">insertItem</a>( "Help!", this, SLOT(giveHelp()), CTRL+Key_H ); + + <a href="qobject.html#connect">connect</a>( options, SIGNAL(<a href="qpopupmenu.html#activated">activated</a>(int)), this, SLOT(doOption(int)) ); + + status = new <a href="qlabel.html">QLabel</a>(this); + status-><a href="qframe.html#setFrameStyle">setFrameStyle</a>( QFrame::WinPanel | QFrame::Sunken ); +<a name="x1354"></a> status-><a href="qwidget.html#setFixedHeight">setFixedHeight</a>( <a href="qwidget.html#fontMetrics">fontMetrics</a>().height() + 4 ); + + <a href="qwidget.html#setMouseTracking">setMouseTracking</a>( TRUE ); +} + +ImageViewer::~ImageViewer() +{ + if ( alloc_context ) +<a name="x1313"></a> QColor::<a href="qcolor.html#destroyAllocContext">destroyAllocContext</a>( alloc_context ); + if ( other == this ) + other = 0; +} + +/* + This function modifies the conversion_flags when an options menu item + is selected, then ensures all menu items are up to date, and reconverts + the image if possibly necessary. +*/ +void <a name="f406"></a>ImageViewer::doOption(int item) +{ + if ( item == ss || item == cc ) { + // Toggle +<a name="x1329"></a> bool newbool = !options-><a href="qmenudata.html#isItemChecked">isItemChecked</a>(item); +<a name="x1330"></a> options-><a href="qmenudata.html#setItemChecked">setItemChecked</a>(item, newbool); + // And reconvert... + reconvertImage(); + <a href="qwidget.html#repaint">repaint</a>(image.hasAlphaBuffer()); // show image in widget + return; + } + + if ( options-><a href="qmenudata.html#isItemChecked">isItemChecked</a>( item ) ) return; // They are all radio buttons + + int ocf = conversion_flags; + + if ( item == ac ) { + conversion_flags = ( conversion_flags & ~ColorMode_Mask ) | AutoColor; + } else if ( item == co ) { + conversion_flags = ( conversion_flags & ~ColorMode_Mask ) | ColorOnly; + } else if ( item == mo ) { + conversion_flags = ( conversion_flags & ~ColorMode_Mask ) | MonoOnly; + } else if ( item == fd ) { + conversion_flags = ( conversion_flags & ~Dither_Mask ) | DiffuseDither; + } else if ( item == bd ) { + conversion_flags = ( conversion_flags & ~Dither_Mask ) | OrderedDither; + } else if ( item == td ) { + conversion_flags = ( conversion_flags & ~Dither_Mask ) | ThresholdDither; + } else if ( item == ta ) { + conversion_flags = ( conversion_flags & ~AlphaDither_Mask ) | ThresholdAlphaDither; + } else if ( item == fa ) { + conversion_flags = ( conversion_flags & ~AlphaDither_Mask ) | DiffuseAlphaDither; + } else if ( item == ba ) { + conversion_flags = ( conversion_flags & ~AlphaDither_Mask ) | OrderedAlphaDither; + } else if ( item == ad ) { + conversion_flags = ( conversion_flags & ~DitherMode_Mask ) | PreferDither; + } else if ( item == dd ) { + conversion_flags = ( conversion_flags & ~DitherMode_Mask ) | AvoidDither; + } + + if ( ocf != conversion_flags ) { + setMenuItemFlags(); + // And reconvert... + reconvertImage(); + <a href="qwidget.html#repaint">repaint</a>(image.hasAlphaBuffer()); // show image in widget + } +} + +/* + Set the options menu to reflect the conversion_flags value. +*/ +void <a name="f407"></a>ImageViewer::setMenuItemFlags() +{ + // File + bool valid_image = pm.size() != QSize( 0, 0 ); + file-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( si, valid_image ); + file-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( sp, valid_image ); + + // Edit + edit-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( t1, image.depth() != 1 ); + edit-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( t8, image.depth() != 8 ); + edit-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( t32, image.depth() != 32 ); + + // Options + bool may_need_color_dithering = + !valid_image + || image.depth() == 32 && QPixmap::<a href="qpixmap.html#defaultDepth">defaultDepth</a>() < 24; + bool may_need_dithering = may_need_color_dithering + || image.depth() > 1 && options-><a href="qmenudata.html#isItemChecked">isItemChecked</a>(mo) + || image.depth() > 1 && QPixmap::<a href="qpixmap.html#defaultDepth">defaultDepth</a>() == 1; + bool has_alpha_mask = !valid_image || image.hasAlphaBuffer(); + + options-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( fd, may_need_dithering ); + options-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( bd, may_need_dithering ); + options-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( td, may_need_dithering ); + + options-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( ta, has_alpha_mask ); + options-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( fa, has_alpha_mask ); + options-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( ba, has_alpha_mask ); + + options-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( ad, may_need_color_dithering ); + options-><a href="qmenudata.html#setItemEnabled">setItemEnabled</a>( dd, may_need_color_dithering ); + + options-><a href="qmenudata.html#setItemChecked">setItemChecked</a>( ac, (conversion_flags & ColorMode_Mask) == AutoColor ); + options-><a href="qmenudata.html#setItemChecked">setItemChecked</a>( co, (conversion_flags & ColorMode_Mask) == ColorOnly ); + options-><a href="qmenudata.html#setItemChecked">setItemChecked</a>( mo, (conversion_flags & ColorMode_Mask) == MonoOnly ); + options-><a href="qmenudata.html#setItemChecked">setItemChecked</a>( fd, (conversion_flags & Dither_Mask) == DiffuseDither ); + options-><a href="qmenudata.html#setItemChecked">setItemChecked</a>( bd, (conversion_flags & Dither_Mask) == OrderedDither ); + options-><a href="qmenudata.html#setItemChecked">setItemChecked</a>( td, (conversion_flags & Dither_Mask) == ThresholdDither ); + options-><a href="qmenudata.html#setItemChecked">setItemChecked</a>( ta, (conversion_flags & AlphaDither_Mask) == ThresholdAlphaDither ); + options-><a href="qmenudata.html#setItemChecked">setItemChecked</a>( fa, (conversion_flags & AlphaDither_Mask) == DiffuseAlphaDither ); + options-><a href="qmenudata.html#setItemChecked">setItemChecked</a>( ba, (conversion_flags & AlphaDither_Mask) == OrderedAlphaDither ); + options-><a href="qmenudata.html#setItemChecked">setItemChecked</a>( ad, (conversion_flags & DitherMode_Mask) == PreferDither ); + options-><a href="qmenudata.html#setItemChecked">setItemChecked</a>( dd, (conversion_flags & DitherMode_Mask) == AvoidDither ); +} + +void <a name="f408"></a>ImageViewer::updateStatus() +{ + if ( pm.size() == QSize( 0, 0 ) ) { + if ( !filename.isEmpty() ) + status-><a href="qlabel.html#setText">setText</a>("Could not load image"); + else + status-><a href="qlabel.html#setText">setText</a>("No image - select Open from File menu."); + } else { + <a href="qstring.html">QString</a> message, moremsg; + message.<a href="qstring.html#sprintf">sprintf</a>("%dx%d", image.width(), image.height()); + if ( pm.size() != pmScaled.size() ) { + moremsg.sprintf(" [%dx%d]", pmScaled.width(), + pmScaled.height()); + message += moremsg; + } + moremsg.sprintf(", %d bits ", image.depth()); + message += moremsg; + if (image.valid(pickx,picky)) { + moremsg.sprintf("(%d,%d)=#%0*x ", + pickx, picky, + image.hasAlphaBuffer() ? 8 : 6, + image.pixel(pickx,picky)); + message += moremsg; + } + if ( image.numColors() > 0 ) { + if (image.valid(pickx,picky)) { + moremsg.sprintf(", %d/%d colors", image.pixelIndex(pickx,picky), + image.numColors()); + } else { + moremsg.sprintf(", %d colors", image.numColors()); + } + message += moremsg; + } + if ( image.hasAlphaBuffer() ) { + if ( image.depth() == 8 ) { + int i; + bool alpha[256]; + int nalpha=0; + + for (i=0; i<256; i++) + alpha[i] = FALSE; + + for (i=0; i<image.numColors(); i++) { + int alevel = image.color(i) >> 24; + if (!alpha[alevel]) { + alpha[alevel] = TRUE; + nalpha++; + } + } + moremsg.sprintf(", %d alpha levels", nalpha); + } else { + // Too many pixels to bother counting. + moremsg = ", 8-bit alpha channel"; + } + message += moremsg; + } + status-><a href="qlabel.html#setText">setText</a>(message); + } +} + +/* + This function saves the image. +*/ +void <a name="f409"></a>ImageViewer::saveImage( int item ) +{ +<a name="x1332"></a> const char* fmt = saveimage-><a href="qmenudata.html#text">text</a>(item); +<a name="x1319"></a> <a href="qstring.html">QString</a> savefilename = QFileDialog::<a href="qfiledialog.html#getSaveFileName">getSaveFileName</a>(QString::null, <a href="qstring.html#QString-null">QString::null</a>, + this, filename); + if ( !savefilename.<a href="qstring.html#isEmpty">isEmpty</a>() ) + if ( !image.save( savefilename, fmt ) ) +<a name="x1333"></a> QMessageBox::<a href="qmessagebox.html#warning">warning</a>( this, "Save failed", "Error saving file" ); +} + +/* + This function saves the converted image. +*/ +void <a name="f410"></a>ImageViewer::savePixmap( int item ) +{ + const char* fmt = savepixmap-><a href="qmenudata.html#text">text</a>(item); + <a href="qstring.html">QString</a> savefilename = QFileDialog::<a href="qfiledialog.html#getSaveFileName">getSaveFileName</a>(QString::null, + QString::null, this, filename); + if ( !savefilename.<a href="qstring.html#isEmpty">isEmpty</a>() ) + if ( !pmScaled.save( savefilename, fmt ) ) + QMessageBox::<a href="qmessagebox.html#warning">warning</a>( this, "Save failed", "Error saving file" ); +} + + +void <a name="f411"></a>ImageViewer::newWindow() +{ + ImageViewer* that = new ImageViewer(0, "new window", WDestructiveClose); + that->options-><a href="qmenudata.html#setItemChecked">setItemChecked</a>( that->cc, useColorContext() ); + that-><a href="qwidget.html#show">show</a>(); +} + +/* + This function is the slot for processing the Open menu item. +*/ +void <a name="f412"></a>ImageViewer::openFile() +{ +<a name="x1318"></a> <a href="qstring.html">QString</a> newfilename = QFileDialog::<a href="qfiledialog.html#getOpenFileName">getOpenFileName</a>( QString::null, + QString::null, + this ); + if ( !newfilename.<a href="qstring.html#isEmpty">isEmpty</a>() ) { + loadImage( newfilename ) ; + <a href="qwidget.html#repaint">repaint</a>(); // show image in widget + } +} + +/* + This function loads an image from a file and resizes the widget to + exactly fit the image size. If the file was not found or the image + format was unknown it will resize the widget to fit the errorText + message (see above) displayed in the current font. + + Returns TRUE if the image was successfully loaded. +*/ + +bool <a name="f413"></a>ImageViewer::loadImage( const <a href="qstring.html">QString</a>& fileName ) +{ + filename = fileName; + bool ok = FALSE; + if ( !filename.isEmpty() ) { +<a name="x1312"></a> QApplication::<a href="qapplication.html#setOverrideCursor">setOverrideCursor</a>( waitCursor ); // this might take time + ok = image.load(filename, 0); + pickx = -1; + clickx = -1; + if ( ok ) + ok = reconvertImage(); + if ( ok ) { + <a href="qwidget.html#setCaption">setCaption</a>( filename ); // set window caption + int w = pm.width(); + int h = pm.height(); + + const int reasonable_width = 128; + if ( w < reasonable_width ) { + // Integer scale up to something reasonable + int multiply = ( reasonable_width + w - 1 ) / w; + w *= multiply; + h *= multiply; + } + +<a name="x1347"></a><a name="x1325"></a> h += menubar-><a href="qmenubar.html#heightForWidth">heightForWidth</a>(w) + status-><a href="qwidget.html#height">height</a>(); + <a href="qwidget.html#resize">resize</a>( w, h ); // we resize to fit image + } else { + pm.resize(0,0); // couldn't load image + <a href="qwidget.html#update">update</a>(); + } +<a name="x1311"></a> QApplication::<a href="qapplication.html#restoreOverrideCursor">restoreOverrideCursor</a>(); // restore original cursor + } + updateStatus(); + setMenuItemFlags(); + return ok; +} + +bool <a name="f414"></a>ImageViewer::reconvertImage() +{ + bool success = FALSE; + + if ( image.isNull() ) return FALSE; + + if ( alloc_context ) { + QColor::<a href="qcolor.html#destroyAllocContext">destroyAllocContext</a>( alloc_context ); + alloc_context = 0; + } + if ( useColorContext() ) { +<a name="x1314"></a> alloc_context = QColor::<a href="qcolor.html#enterAllocContext">enterAllocContext</a>(); + // Clear the image to hide flickering palette + <a href="qpainter.html">QPainter</a> painter(this); +<a name="x1338"></a> painter.<a href="qpainter.html#eraseRect">eraseRect</a>(0, menubar-><a href="qmenubar.html#heightForWidth">heightForWidth</a>( <a href="qwidget.html#width">width</a>() ), width(), height()); + } + + QApplication::<a href="qapplication.html#setOverrideCursor">setOverrideCursor</a>( waitCursor ); // this might take time + if ( pm.convertFromImage(image, conversion_flags) ) + { + pmScaled = QPixmap(); + scale(); + <a href="qwidget.html#resize">resize</a>( <a href="qwidget.html#width">width</a>(), height() ); + success = TRUE; // load successful + } else { + pm.resize(0,0); // couldn't load image + } + updateStatus(); + setMenuItemFlags(); + QApplication::<a href="qapplication.html#restoreOverrideCursor">restoreOverrideCursor</a>(); // restore original cursor + + if ( useColorContext() ) +<a name="x1315"></a> QColor::<a href="qcolor.html#leaveAllocContext">leaveAllocContext</a>(); + + return success; // TRUE if loaded OK +} + +bool <a name="f415"></a>ImageViewer::smooth() const +{ + return options-><a href="qmenudata.html#isItemChecked">isItemChecked</a>(ss); +} + +bool <a name="f416"></a>ImageViewer::useColorContext() const +{ + return options-><a href="qmenudata.html#isItemChecked">isItemChecked</a>(cc); +} + +/* + This functions scales the pixmap in the member variable "pm" to fit the + widget size and puts the resulting pixmap in the member variable "pmScaled". +*/ + +void <a name="f417"></a>ImageViewer::scale() +{ + int h = <a href="qwidget.html#height">height</a>() - menubar-><a href="qmenubar.html#heightForWidth">heightForWidth</a>( <a href="qwidget.html#width">width</a>() ) - status-><a href="qwidget.html#height">height</a>(); + + if ( image.isNull() ) return; + + QApplication::<a href="qapplication.html#setOverrideCursor">setOverrideCursor</a>( waitCursor ); // this might take time + if ( <a href="qwidget.html#width">width</a>() == pm.width() && h == pm.height() ) + { // no need to scale if widget + pmScaled = pm; // size equals pixmap size + } else { + if (smooth()) { + pmScaled.convertFromImage(image.smoothScale(<a href="qwidget.html#width">width</a>(), h), + conversion_flags); + } else { + <a href="qwmatrix.html">QWMatrix</a> m; // <a href="qwmatrix.html#TransformationMode">transformation matrix</a> +<a name="x1357"></a> m.<a href="qwmatrix.html#scale">scale</a>(((double)<a href="qwidget.html#width">width</a>())/pm.width(),// define scale factors + ((double)h)/pm.height()); + pmScaled = pm.xForm( m ); // create scaled pixmap + } + } + QApplication::<a href="qapplication.html#restoreOverrideCursor">restoreOverrideCursor</a>(); // restore original cursor +} + +/* + The resize event handler, if a valid pixmap was loaded it will call + scale() to fit the pixmap to the new widget size. +*/ + +<a name="x1353"></a>void ImageViewer::<a href="qwidget.html#resizeEvent">resizeEvent</a>( <a href="qresizeevent.html">QResizeEvent</a> * ) +{ +<a name="x1355"></a> status-><a href="qwidget.html#setGeometry">setGeometry</a>(0, height() - status-><a href="qwidget.html#height">height</a>(), + <a href="qwidget.html#width">width</a>(), status-><a href="qwidget.html#height">height</a>()); + + if ( pm.size() == QSize( 0, 0 ) ) // we couldn't load the image + return; + + int h = <a href="qwidget.html#height">height</a>() - menubar-><a href="qmenubar.html#heightForWidth">heightForWidth</a>( <a href="qwidget.html#width">width</a>() ) - status-><a href="qwidget.html#height">height</a>(); + if ( <a href="qwidget.html#width">width</a>() != pmScaled.width() || h != pmScaled.height()) + { // if new size, + scale(); // scale pmScaled to window + updateStatus(); + } + if ( image.hasAlphaBuffer() ) + <a href="qwidget.html#erase">erase</a>(); +} + +bool <a name="f418"></a>ImageViewer::convertEvent( <a href="qmouseevent.html">QMouseEvent</a>* e, int& x, int& y) +{ + if ( pm.size() != QSize( 0, 0 ) ) { + int h = <a href="qwidget.html#height">height</a>() - menubar-><a href="qmenubar.html#heightForWidth">heightForWidth</a>( <a href="qwidget.html#width">width</a>() ) - status-><a href="qwidget.html#height">height</a>(); +<a name="x1335"></a> int nx = e-><a href="qmouseevent.html#x">x</a>() * image.width() / width(); +<a name="x1336"></a> int ny = (e-><a href="qmouseevent.html#y">y</a>()-menubar-><a href="qmenubar.html#heightForWidth">heightForWidth</a>( <a href="qwidget.html#width">width</a>() )) * image.height() / h; + if (nx != x || ny != y ) { + x = nx; + y = ny; + updateStatus(); + return TRUE; + } + } + return FALSE; +} + +void ImageViewer::<a href="qwidget.html#mousePressEvent">mousePressEvent</a>( <a href="qmouseevent.html">QMouseEvent</a> *e ) +{ + may_be_other = convertEvent(e, clickx, clicky); +} + +<a name="x1350"></a>void ImageViewer::<a href="qwidget.html#mouseReleaseEvent">mouseReleaseEvent</a>( <a href="qmouseevent.html">QMouseEvent</a> * ) +{ + if ( may_be_other ) + other = this; +} + +/* + Record the pixel position of interest. +*/ +void ImageViewer::<a href="qwidget.html#mouseMoveEvent">mouseMoveEvent</a>( <a href="qmouseevent.html">QMouseEvent</a> *e ) +{ + if (convertEvent(e,pickx,picky)) { + updateStatus(); +<a name="x1334"></a> if ((e-><a href="qmouseevent.html#state">state</a>()&LeftButton)) { + may_be_other = FALSE; + if ( clickx >= 0 && other) { + copyFrom(other); + } + } + } +} + +/* + Draws the portion of the scaled pixmap that needs to be updated or prints + an error message if no legal pixmap has been loaded. +*/ + +void ImageViewer::<a href="qwidget.html#paintEvent">paintEvent</a>( <a href="qpaintevent.html">QPaintEvent</a> *e ) +{ + if ( pm.size() != QSize( 0, 0 ) ) { // is an image loaded? + <a href="qpainter.html">QPainter</a> painter(this); +<a name="x1340"></a><a name="x1339"></a> painter.<a href="qpainter.html#setClipRect">setClipRect</a>(e-><a href="qpaintevent.html#rect">rect</a>()); +<a name="x1337"></a> painter.<a href="qpainter.html#drawPixmap">drawPixmap</a>(0, menubar-><a href="qmenubar.html#heightForWidth">heightForWidth</a>( <a href="qwidget.html#width">width</a>() ), pmScaled); + } +} + + +/* + Explain anything that might be confusing. +*/ +void <a name="f419"></a>ImageViewer::giveHelp() +{ + if (!helpmsg) { + <a href="qstring.html">QString</a> helptext = + "<b>Usage:</b> <tt>showimg [-m] <i>filename ...</i></tt>" + "<blockquote>" + "<tt>-m</tt> - use <i>ManyColor</i> color spec" + "</blockquote>" + "<p>Supported input formats:" + "<blockquote>"; +<a name="x1321"></a> helptext += QImage::<a href="qimage.html#inputFormatList">inputFormatList</a>().join(", "); + helptext += "</blockquote>"; + + helpmsg = new <a href="qmessagebox.html">QMessageBox</a>( "Help", helptext, + QMessageBox::Information, QMessageBox::Ok, 0, 0, 0, 0, FALSE ); + } +<a name="x1317"></a> helpmsg-><a href="qdialog.html#show">show</a>(); +<a name="x1352"></a> helpmsg-><a href="qwidget.html#raise">raise</a>(); +} + +void <a name="f420"></a>ImageViewer::copyFrom(ImageViewer* s) +{ + if ( clickx >= 0 ) { + int dx = clickx; + int dy = clicky; + int sx = s->clickx; + int sy = s->clicky; + int sw = QABS(clickx - pickx)+1; + int sh = QABS(clicky - picky)+1; + if ( clickx > pickx ) { + dx = pickx; + sx -= sw-1; + } + if ( clicky > picky ) { + dy = picky; + sy -= sh-1; + } + <a href="qimage.html#bitBlt">bitBlt</a>( &image, dx, dy, &s->image, sx, sy, sw, sh ); + reconvertImage(); + <a href="qwidget.html#repaint">repaint</a>( image.hasAlphaBuffer() ); + } +} +ImageViewer* ImageViewer::other = 0; + +void <a name="f421"></a>ImageViewer::hFlip() +{ + setImage(image.mirror(TRUE,FALSE)); +} + +void <a name="f422"></a>ImageViewer::vFlip() +{ + setImage(image.mirror(FALSE,TRUE)); +} + +void <a name="f423"></a>ImageViewer::rot180() +{ + setImage(image.mirror(TRUE,TRUE)); +} + +void <a name="f424"></a>ImageViewer::copy() +{ +#ifndef QT_NO_MIMECLIPBOARD +<a name="x1308"></a> QApplication::<a href="qapplication.html#clipboard">clipboard</a>()->setImage(image); // Less information loss +#endif +} + +void <a name="f425"></a>ImageViewer::paste() +{ +#ifndef QT_NO_MIMECLIPBOARD + <a href="qimage.html">QImage</a> p = QApplication::<a href="qapplication.html#clipboard">clipboard</a>()->image(); +<a name="x1322"></a> if ( !p.<a href="qimage.html#isNull">isNull</a>() ) { + filename = "pasted"; + setImage(p); + } +#endif +} + +void <a name="f426"></a>ImageViewer::setImage(const <a href="qimage.html">QImage</a>& newimage) +{ + image = newimage; + + pickx = -1; + clickx = -1; + <a href="qwidget.html#setCaption">setCaption</a>( filename ); // set window caption + int w = image.width(); + int h = image.height(); + if ( !w ) + return; + + const int reasonable_width = 128; + if ( w < reasonable_width ) { + // Integer scale up to something reasonable + int multiply = ( reasonable_width + w - 1 ) / w; + w *= multiply; + h *= multiply; + } + + h += menubar-><a href="qmenubar.html#heightForWidth">heightForWidth</a>(w) + status-><a href="qwidget.html#height">height</a>(); + <a href="qwidget.html#resize">resize</a>( w, h ); // we resize to fit image + + reconvertImage(); + <a href="qwidget.html#repaint">repaint</a>( image.hasAlphaBuffer() ); + + updateStatus(); + setMenuItemFlags(); +} + +void <a name="f427"></a>ImageViewer::editText() +{ + ImageTextEditor editor(image,this); + editor.<a href="qdialog.html#exec">exec</a>(); +} + +void <a name="f428"></a>ImageViewer::to1Bit() +{ + toBitDepth(1); +} + +void <a name="f429"></a>ImageViewer::to8Bit() +{ + toBitDepth(8); +} + +void <a name="f430"></a>ImageViewer::to32Bit() +{ + toBitDepth(32); +} + +void <a name="f431"></a>ImageViewer::toBitDepth(int d) +{ + image = image.convertDepth(d); + reconvertImage(); + <a href="qwidget.html#repaint">repaint</a>( image.hasAlphaBuffer() ); +} +</pre> + +<p> <hr> +<p> Main: +<p> <pre>/**************************************************************************** +** $Id: qt/main.cpp 3.3.8 edited Jan 11 14:37 $ +** +** Copyright (C) 1992-2007 Trolltech ASA. All rights reserved. +** +** This file is part of an example program for Qt. This example +** program may be used, distributed and modified without limitation. +** +*****************************************************************************/ + +#include "showimg.h" +#include "imagefip.h" +#include <<a href="qapplication-h.html">qapplication.h</a>> +#include <<a href="qimage-h.html">qimage.h</a>> + +int main( int argc, char **argv ) +{ + if ( argc > 1 && QString(argv[1]) == "-m" ) { +<a name="x1361"></a> QApplication::<a href="qapplication.html#setColorSpec">setColorSpec</a>( QApplication::ManyColor ); + argc--; + argv++; + } + else if ( argc > 1 && QString(argv[1]) == "-n" ) { + QApplication::<a href="qapplication.html#setColorSpec">setColorSpec</a>( QApplication::NormalColor ); + argc--; + argv++; + } + else { + QApplication::<a href="qapplication.html#setColorSpec">setColorSpec</a>( QApplication::CustomColor ); + } + + <a href="qapplication.html">QApplication</a> a( argc, argv ); + + ImageIconProvider iip; +<a name="x1362"></a> QFileDialog::<a href="qfiledialog.html#setIconProvider">setIconProvider</a>( &iip ); + + if ( argc <= 1 ) { + // Create a window which looks after its own existence. + ImageViewer *w = + new ImageViewer(0, "new window", Qt::WDestructiveClose | Qt::WResizeNoErase ); +<a name="x1364"></a> w-><a href="qwidget.html#setCaption">setCaption</a>("Qt Example - Image Viewer"); + w-><a href="qwidget.html#show">show</a>(); + } else { + for ( int i=1; i<argc; i++ ) { + // Create a window which looks after its own existence. + ImageViewer *w = + new ImageViewer(0, argv[i], Qt::WDestructiveClose | Qt::WResizeNoErase ); + w-><a href="qwidget.html#setCaption">setCaption</a>("Qt Example - Image Viewer"); + w->loadImage( argv[i] ); + w-><a href="qwidget.html#show">show</a>(); + } + } + + QObject::<a href="qobject.html#connect">connect</a>(qApp, SIGNAL(<a href="qapplication.html#lastWindowClosed">lastWindowClosed</a>()), qApp, SLOT(<a href="qapplication.html#quit">quit</a>())); + + return a.<a href="qapplication.html#exec">exec</a>(); +} +</pre> + +<p>See also <a href="examples.html">Examples</a>. + +<!-- eof --> +<p><address><hr><div align=center> +<table width=100% cellspacing=0 border=0><tr> +<td>Copyright © 2007 +<a href="troll.html">Trolltech</a><td align=center><a href="trademarks.html">Trademarks</a> +<td align=right><div align=right>Qt 3.3.8</div> +</table></div></address></body> +</html> |