showimg-main-cpp.html

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    } 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 ) {
        <a href=#370>setMenuItemFlags</a>();
        // And reconvert...
        <a href=#377>reconvertImage</a>();
        <a href="qwidget.html#7569b1">repaint</a>(image.hasAlphaBuffer());        // show image in widget
    }
}

/*
  Set the options menu to reflect the conversion_flags value.
*/
void <a name="370"></a>ImageViewer::setMenuItemFlags()
{
    // File
    bool valid_image = pm.size() != QSize( 0, 0 );
    file-&gt;setItemEnabled( si, valid_image );
    file-&gt;setItemEnabled( sp, valid_image );

    // Edit
    edit-&gt;setItemEnabled( t1, image.depth() != 1 );
    edit-&gt;setItemEnabled( t8, image.depth() != 8 );
    edit-&gt;setItemEnabled( t32, image.depth() != 32 );

    // Options
    bool may_need_color_dithering =
            !valid_image
        || image.depth() == 32 &amp;&amp; <a href="qpixmap.html#e194ad">QPixmap::defaultDepth</a>() &lt; 24;
    bool may_need_dithering = may_need_color_dithering
         || image.depth() &gt; 1 &amp;&amp; options-&gt;isItemChecked(mo)
         || image.depth() &gt; 1 &amp;&amp; <a href="qpixmap.html#e194ad">QPixmap::defaultDepth</a>() == 1;
    bool has_alpha_mask = !valid_image || image.hasAlphaBuffer();

    options-&gt;setItemEnabled( fd, may_need_dithering );
    options-&gt;setItemEnabled( bd, may_need_dithering );
    options-&gt;setItemEnabled( td, may_need_dithering );

    options-&gt;setItemEnabled( ta, has_alpha_mask );
    options-&gt;setItemEnabled( fa, has_alpha_mask );
    options-&gt;setItemEnabled( ba, has_alpha_mask );

    options-&gt;setItemEnabled( ad, may_need_color_dithering );
    options-&gt;setItemEnabled( dd, may_need_color_dithering );

    options-&gt;setItemChecked( ac, (conversion_flags &amp; ColorMode_Mask) == AutoColor );
    options-&gt;setItemChecked( co, (conversion_flags &amp; ColorMode_Mask) == ColorOnly );
    options-&gt;setItemChecked( mo, (conversion_flags &amp; ColorMode_Mask) == MonoOnly );
    options-&gt;setItemChecked( fd, (conversion_flags &amp; Dither_Mask) == DiffuseDither );
    options-&gt;setItemChecked( bd, (conversion_flags &amp; Dither_Mask) == OrderedDither );
    options-&gt;setItemChecked( td, (conversion_flags &amp; Dither_Mask) == ThresholdDither );
    options-&gt;setItemChecked( ta, (conversion_flags &amp; AlphaDither_Mask) == ThresholdAlphaDither );
    options-&gt;setItemChecked( fa, (conversion_flags &amp; AlphaDither_Mask) == DiffuseAlphaDither );
    options-&gt;setItemChecked( ba, (conversion_flags &amp; AlphaDither_Mask) == OrderedAlphaDither );
    options-&gt;setItemChecked( ad, (conversion_flags &amp; DitherMode_Mask) == PreferDither );
    options-&gt;setItemChecked( dd, (conversion_flags &amp; DitherMode_Mask) == AvoidDither );
}

void <a name="371"></a>ImageViewer::updateStatus()
{
    if ( pm.size() == QSize( 0, 0 ) ) {
        if ( filename )
            status-&gt;setText("Could not load image");
        else
            status-&gt;setText("No image - select Open from File menu.");
    } else {
        <a href="qstring.html">QString</a> message, moremsg;
        message.<a href="qstring.html#926f67">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() &gt; 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&lt;256; i++)
                    alpha[i] = FALSE;

                for (i=0; i&lt;image.numColors(); i++) {
                    int alevel = image.color(i) &gt;&gt; 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-&gt;setText(message);
    }
}

/*
  This function saves the image.
*/
void <a name="372"></a>ImageViewer::saveImage( int item )
{
    const char* fmt = saveimage-&gt;text(item);
    <a href="qstring.html">QString</a> savefilename = QFileDialog::getSaveFileName(QString::null, QString::null,
                                        this, filename);
    if ( !savefilename.<a href="qstring.html#c62623">isEmpty</a>() )
        if ( !image.save( savefilename, fmt ) )
            <a href="qmessagebox.html#63edba">QMessageBox::warning</a>( this, "Save failed", "Error saving file" );
}

/*
  This function saves the converted image.
*/
void <a name="373"></a>ImageViewer::savePixmap( int item )
{
    const char* fmt = savepixmap-&gt;text(item);
    <a href="qstring.html">QString</a> savefilename = QFileDialog::getSaveFileName(QString::null,
                                        QString::null, this, filename);
    if ( !savefilename.<a href="qstring.html#c62623">isEmpty</a>() )
        if ( !pmScaled.save( savefilename, fmt ) )
            <a href="qmessagebox.html#63edba">QMessageBox::warning</a>( this, "Save failed", "Error saving file" );
}

void <a name="374"></a>ImageViewer::newWindow()
{
    ImageViewer* that = new ImageViewer(0, "new window", WDestructiveClose);
    that-&gt;options-&gt;setItemChecked( that-&gt;cc, <a href=#380>useColorContext</a>() );
    that-&gt;<a href="qwidget.html#200ee5">show</a>();
}

/*
  This function is the slot for processing the Open menu item.
*/
void <a name="375"></a>ImageViewer::openFile()
{
    <a href="qstring.html">QString</a> newfilename = QFileDialog::getOpenFileName();
    if ( !newfilename.<a href="qstring.html#c62623">isEmpty</a>() ) {
        <a href=#376>loadImage</a>( newfilename ) ;
        <a href="qwidget.html#7569b1">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="376"></a>ImageViewer::loadImage( const char *fileName )
{
    filename = fileName;
    bool ok = FALSE;
    if ( filename ) {
        <a href="qapplication.html#07e1f1">QApplication::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#d6a291">setCaption</a>( filename );                     // set window caption
            int w = pm.width();
            int h = pm.height();

            const int reasonable_width = 128;
            if ( w &lt; reasonable_width ) {
                // Integer scale up to something reasonable
                int multiply = ( reasonable_width + w - 1 ) / w;
                w *= multiply;
                h *= multiply;
            }

            h += menubar-&gt;heightForWidth(w) + status-&gt;height();
            <a href="qwidget.html#8fcbbe">resize</a>( w, h );                             // we resize to fit image
        } else {
            pm.resize(0,0);                             // couldn't load image
            <a href="qwidget.html#a66a88">update</a>();
        }
        <a href="qapplication.html#655095">QApplication::restoreOverrideCursor</a>();  // restore original cursor
    }
    <a href=#371>updateStatus</a>();
    <a href=#370>setMenuItemFlags</a>();
    return ok;
}

bool <a name="377"></a>ImageViewer::reconvertImage()
{
    bool success = FALSE;

    if ( image.isNull() ) return FALSE;

    if ( alloc_context ) {
        <a href="qcolor.html#cc0257">QColor::destroyAllocContext</a>( alloc_context );
        alloc_context = 0;
    }
    if ( useColorContext() ) {
        alloc_context = QColor::enterAllocContext();
        // Clear the image to hide flickering palette
        <a href="qpainter.html">QPainter</a> painter(this);
        painter.<a href="qpainter.html#bd5570">eraseRect</a>(0, menubar-&gt;heightForWidth( <a href="qwidget.html#2edab1">width</a>() ), <a href="qwidget.html#2edab1">width</a>(), <a href="qwidget.html#e3c588">height</a>());
    }

    <a href="qapplication.html#07e1f1">QApplication::setOverrideCursor</a>( waitCursor ); // this might take time
    if ( pm.convertFromImage(image, conversion_flags) )
    {
        pmScaled = QPixmap();
        <a href=#381>scale</a>();
        <a href="qwidget.html#8fcbbe">resize</a>( width(), <a href="qwidget.html#e3c588">height</a>() );
        success = TRUE;                         // load successful
    } else {
        pm.resize(0,0);                         // couldn't load image
    }
    <a href=#371>updateStatus</a>();
    <a href=#370>setMenuItemFlags</a>();
    <a href="qapplication.html#655095">QApplication::restoreOverrideCursor</a>();      // restore original cursor

    if ( useColorContext() )
        <a href="qcolor.html#30fe87">QColor::leaveAllocContext</a>();

    return success;                             // TRUE if loaded OK
}

bool <a name="378"></a>ImageViewer::unscaled() const
{
    return options-&gt;isItemChecked(ns);
}

bool <a name="379"></a>ImageViewer::smooth() const
{
    return options-&gt;isItemChecked(ss);
}

bool <a name="380"></a>ImageViewer::useColorContext() const
{
    return options-&gt;isItemChecked(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="381"></a>ImageViewer::scale()
{
    int h = height() - menubar-&gt;heightForWidth( <a href="qwidget.html#2edab1">width</a>() ) - status-&gt;height();

    if ( image.isNull() ) return;

    <a href="qapplication.html#07e1f1">QApplication::setOverrideCursor</a>( waitCursor ); // this might take time
    if ( width() == pm.width() &amp;&amp; h == pm.height() || unscaled() )
    {                                           // no need to scale if widget
        pmScaled = pm;                          // size equals pixmap size
    } else {
        if (smooth()) {
            pmScaled.convertFromImage(image.smoothScale(<a href="qwidget.html#2edab1">width</a>(), h),
                conversion_flags);