effects.cpp

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#include <qimage.h>
#include <qpixmap.h>
#include <qcolor.h>

#include "effects.h"



QImage & QImageEffect::fade (QImage & img, float val, const QColor & color)
{
        if ( img. width ( ) == 0 || img. height ( ) == 0 )
                return img;

// We don't handle bitmaps
      if (img.depth () == 1)
        return img;

    unsigned char
    tbl[256];
    for (int i = 0; i < 256; i++)
        tbl[i] = (int) (val * i + 0.5);

    int
    red =
    color.
    red ();
    int
    green =
    color.
    green ();
    int
    blue =
    color.
    blue ();

    QRgb col;
    int
    r,
    g,
    b,
    cr,
    cg,
    cb;

    if (img.depth () <= 8)
    {
                                // pseudo color
            for (int i = 0; i < img.numColors (); i++)
        {
                col = img.color (i);
                cr = qRed (col);
          cg = qGreen (col);
                cb=qBlue(col);
                                if (cr > red)
                    r = cr - tbl[cr - red];
                
          else
                    r = cr + tbl[red - cr];
                if (cg > green)
                    g = cg - tbl[cg - green];
                
          else
                    g = cg + tbl[green - cg];
                if (cb > blue)
                    b = cb - tbl[cb - blue];
                
          else
                    b = cb + tbl[blue - cb];
                img.setColor (i, qRgb (r, g, b));
            }

      }
  else
    {
                                // truecolor
            for (int y = 0; y < img.height (); y++)
        {
                QRgb * data = (QRgb *) img.scanLine (y);
                for (int x = 0; x < img.width (); x++)
            {
                      col = *data;
                      cr = qRed (col);
cg=qGreen(col);
cb=qBlue(col);
                      if (cr > red)
                          r = cr - tbl[cr - red];
                      
              else
                          r = cr + tbl[red - cr];
                      if (cg > green)
                          g = cg - tbl[cg - green];
                      
              else
                          g = cg + tbl[green - cg];
                      if (cb > blue)
                          b = cb - tbl[cb - blue];
                      
              else
                          b = cb + tbl[blue - cb];
                      *data++ = qRgb (r, g, b);
                  }
            }
      }

    return img;
}



QPixmap& QPixmapEffect::fade(QPixmap &pixmap, float val, const QColor &color)
{
        QImage img = pixmap.convertToImage();
        QImageEffect::fade(img, val, color);
        pixmap.convertFromImage(img);
   
        return pixmap;
}

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