C++ qBlue函数代码示例

void Widget::initializeGL()
{
    timer.setInterval (10);
    timer.setSingleShot(false);
    timer.start();
    connect(&timer, SIGNAL(timeout()), this, SLOT(onTimer()));

    initializeGLFunctions();

    printf("\n%s\n", glGetString(GL_VERSION));
    printf("%s\n", glGetString(GL_VENDOR));
    printf("%s\n", glGetString(GL_RENDERER));
    fflush (stdout);
    QImage part_img (":/match.png");
    for (int line = 0; line < part_img.height(); line++)
    {
        QRgb *pixel = (QRgb *)part_img.scanLine (line);
        for (int b = 0; b < part_img.width(); b++)
            if( 0 == qRed(pixel[b]) &&
                0 == qGreen(pixel[b]) &&
                0 == qBlue(pixel[b])
            ) {
                pixel[b] = 0x00ffffff;
            }
    }

    partTexture = bindTexture (part_img,
                         GL_TEXTURE_2D,
                         GL_RGBA,
                         QGLContext::DefaultBindOption);

    myShader.addShaderFromSourceFile(QGLShader::Vertex, ":/ground.vert");
    myShader.addShaderFromSourceFile(QGLShader::Fragment, ":/ground.frag");
    myShader.link();
    particle.addShaderFromSourceFile(QGLShader::Vertex,":/particle.vert");
    particle.addShaderFromSourceFile(QGLShader::Fragment,":/particle.frag");
    particle.link();

    terrainMesh.loadRawTriangles(":/terrain.raw");

    terrainTexture =bindTexture(QImage(":/terrain.jpg"));
}

// Add random noise to the image
void MainWindow::AddNoise(QImage *image, double mag, bool colorNoise)
{
    int r, c;
    QRgb pixel;
    int noiseMag = mag;
    noiseMag *= 2;

    for(r=0;r<image->height();r++)
    {
        for(c=0;c<image->width();c++)
        {
            pixel = image->pixel(c, r);
            int red = qRed(pixel);
            int green = qGreen(pixel);
            int blue = qBlue(pixel);

            // If colorNoise, add color independently to each channel
            if(colorNoise)
            {
                red += rand()%noiseMag - noiseMag/2;
                green += rand()%noiseMag - noiseMag/2;
                blue += rand()%noiseMag - noiseMag/2;
            }
            // otherwise add the same amount of noise to each channel
            else
            {
                int noise = rand()%noiseMag - noiseMag/2;

                red += noise;
                green += noise;
                blue += noise;
            }

            // Make sure we don't over or under saturate
            red = min(255, max(0, red));
            green = min(255, max(0, green));
            blue = min(255, max(0, blue));

            image->setPixel(c, r, qRgb( red, green, blue));
        }
    }
}

void Histogram::generate(QImage* image)
{
    int width  = image->width();
    int height = image->height();

    if (image->format() == QImage::Format_Indexed8)
    {
        for (int x=0; x<width; x++)
        {	for (int y=0; y<height; y++)
            {
                QRgb pixel = image->pixel(x, y);

                int l = qGray(pixel);
                int value = L-> value(l)+1;
                L -> insert(l, value);

            }
        }
    }
    else
    {
        for (int x=0; x<width; x++)
        {	for (int y=0; y<height; y++)
            {
                QRgb pixel = image->pixel(x, y);

                int r = qRed(pixel);
                int g = qGreen(pixel);
                int b = qBlue(pixel);

                int valueR = R-> value(r)+1;
                int valueG = G-> value(g)+1;
                int valueB = B-> value(b)+1;

                R -> insert(r, valueR);
                G -> insert(g, valueG);
                B -> insert(b, valueB);

            }
        }
    }
}

RGB24Buffer *QTFileLoader::RGB24BufferFromQImage(QImage *image)
{
    if (image == NULL)
        return NULL;

    RGB24Buffer *result = new RGB24Buffer(image->height(), image->width(), false);

    if (image->format() == QImage::Format_ARGB32 || image->format() == QImage::Format_RGB32 )
    {
        for (int i = 0; i < image->height(); i++)
        {
            uint8_t *in = (uint8_t *)image->scanLine(i);
            RGBColor *out = &result->element(i, 0);
            for (int j = 0; j < image->width(); j++)
            {
                uint8_t r = *(in++);
                uint8_t g = *(in++);
                uint8_t b = *(in++);
                *out = RGBColor(b,g,r);
                in++;
                out++;
            }
        }
    } else {
        /**
         * TODO: Make this faster using .bits() method.
         * So far don't want to mess with possible image formats
         *
         */
        qDebug("QTFileLoader::RGB24BufferFromQImage():Slow conversion.");
        for (int i = 0; i < image->height(); i++)
        {
            for (int j = 0; j < image->width(); j++)
            {
                QRgb pixel = image->pixel(j,i);
                result->element(i,j) = RGBColor(qRed(pixel), qGreen(pixel), qBlue(pixel));
            }
        }
    }

    return result;
}

void paintShadow(QPainter *p, const QRect &r, const ShadowSettings &settings, const QImage &shadowImage)
{
    const int s = -settings.size;
    QRect rect = r.adjusted(s - 32, s - 32, 32 - s, 32 - s);
    rect.adjust(settings.offsetX, settings.offsetY, settings.offsetX, settings.offsetY);
    int radius = shadowImage.width() / 2;

    // corners
    for (int i = 0; i < 4; ++i) {
        const int x = i & 1 ? rect.x() : rect.x() + rect.width() - radius;
        const int y = i & 2 ? rect.y() : rect.y() + rect.height() - radius;
        p->drawImage(x, y, shadowImage,
            i & 1 ? 0 : radius + 1, i & 2 ? 0 : radius + 1, radius, radius);
    }

    // sides
    for (int i = 0; i < 2; ++i) {
        const int x = rect.x() + radius;
        const int y = i & 1 ? rect.y() : rect.y() + rect.height() - radius;
        p->drawTiledPixmap(x, y, rect.width() - 2 * radius, radius,
            QPixmap::fromImage(shadowImage.copy(radius, i & 1 ? 0 : radius + 1, 1, radius)));
    }
    for (int i = 0; i < 2; ++i) {
        const int x = i & 1 ? rect.x() : rect.x() + rect.width() - radius;
        const int y = rect.y() + radius;
        p->drawTiledPixmap(x, y, radius, rect.height() - 2 * radius,
            QPixmap::fromImage(shadowImage.copy(i & 1 ? 0 : radius + 1, radius, radius, 1)));
    }

    // center
    QRgb pixel = shadowImage.pixel(radius, radius);
    if (shadowImage.format() == QImage::Format_ARGB32_Premultiplied) {
        const int alpha = qAlpha(pixel);
        if (alpha != 0 && alpha != 255) {
            pixel = qRgba(qBound(0, qRed(pixel) * 255 / alpha, 255),
                qBound(0, qGreen(pixel) * 255 / alpha, 255),
                qBound(0, qBlue(pixel) * 255 / alpha, 255),
                alpha);
        }
    }
    p->fillRect(rect.adjusted(radius, radius, -radius, -radius), QColor::fromRgba(pixel));
}

/**
 * Changes the transparency (alpha component) of an image.
 * @param image Image to be manipulated. Must be true color (8 bit per channel).
 * @param factor > 1.0 == more transparency, < 1.0 == less transparency.
 */
void PlaylistItem::imageTransparency( QImage& image, float factor ) //static
{
    uint *data = reinterpret_cast<unsigned int *>( image.bits() );
    const int pixels = image.width() * image.height();
    uint table[256];
    register int c;

    // Precalculate lookup table
    for( int i = 0; i < 256; ++i ) {
        c = int( double( i ) * factor );
        if( c > 255 ) c = 255;
        table[i] = c;
    }

    // Process all pixels. Highly optimized.
    for( int i = 0; i < pixels; ++i ) {
        c = data[i]; // Memory access is slow, so do it only once
        data[i] = qRgba( qRed( c ), qGreen( c ), qBlue( c ), table[qAlpha( c )] );
    }
}

/*!
  Used to convert RGB Jpg files to grayscale.

  \param image a QImage with original image data points
  \return a grayscale Matrix from QImage
*/
Matrix ImageB::convertRGB2Gray( QImage image )
{
   QRgb pix;
   Matrix mat = Matrix(image.height(),image.width());

   for (long i=1; i <= image.width();i++)
       {
          for(long j=1; j <= image.height();j++) 
            {
              int h =0;
              pix = image.pixel(i,j); //pega valor do pixel
              
              //média dos pixels
              h = int((qRed(pix) + qGreen(pix) + qBlue(pix))/3);            
              mat(j,i) = h; //seta dado na matriz
            } 
       }
  
  return mat;
}

//==============================================================================
void GameServer::LoadLevelFromImage_(const QString filename)
{
  QFile levelImage(filename);
  if (levelImage.exists())
  {
    QImage map;
    map.load(filename, "png");
    levelMap_.Resize(map.width(), map.height());
    for (int i = 0; i < map.height(); i++)
    {
      for (int j = 0; j < map.width(); j++)
      {
        auto color = map.pixel(j, i);
        int summ = qRed(color) + qGreen(color) + qBlue(color);
        int value = summ > (255 * 3 / 2) ? '.' : '#';
        levelMap_.SetCell(j, i, value);
      }
    }
  }
}

static void _binarize(QString sourceFile, QString destFile)
{
    QImage image(sourceFile);
    int width = image.width();
    int height = image.height();
    QRgb color;
    QRgb avg;
    QRgb black = qRgb(0, 0, 0);
    QRgb white = qRgb(255, 255, 255);
    for(int i = 0; i < width; i++)
    {
        for(int j= 0; j < height; j++)
        {
            color = image.pixel(i, j);
            avg = (qRed(color) + qGreen(color) + qBlue(color))/3;
            image.setPixel(i, j, avg >= 128 ? white : black);
        }
    }
    image.save(destFile);
}

void ImageHandler::ghostImage(QImage *img)
{
       
	int w = img->width(),
		h = img->height(),
		x, y;

	for (y=0; y<h; y++)
	{
		uint *line = (uint*)img->scanLine(y);
		for (x=0; x<w; x++)
		{
			//if ((x%2 && !(y%2)) || (!(x%2) && y%2))
			{
				line[x] = qRgba(qRed(line[x]), qGreen(line[x]), qBlue(line[x]), (line[x] ? 125 : 0));
			}
		}
	}

}

static bool fuzzyComparePixels(const QRgb testPixel, const QRgb refPixel, const char* file, int line, int x = -1, int y = -1)
{
    static int maxFuzz = 1;
    static bool maxFuzzSet = false;

    // On 16 bpp systems, we need to allow for more fuzz:
    if (!maxFuzzSet) {
        maxFuzzSet = true;
        if (QGuiApplication::primaryScreen()->depth() < 24)
            maxFuzz = 32;
    }

    int redFuzz = qAbs(qRed(testPixel) - qRed(refPixel));
    int greenFuzz = qAbs(qGreen(testPixel) - qGreen(refPixel));
    int blueFuzz = qAbs(qBlue(testPixel) - qBlue(refPixel));
    int alphaFuzz = qAbs(qAlpha(testPixel) - qAlpha(refPixel));

    if (refPixel != 0 && testPixel == 0) {
        QString msg;
        if (x >= 0) {
            msg = QString("Test pixel [%1, %2] is null (black) when it should be (%3,%4,%5,%6)")
                            .arg(x).arg(y)
                            .arg(qRed(refPixel)).arg(qGreen(refPixel)).arg(qBlue(refPixel)).arg(qAlpha(refPixel));
        } else {
            msg = QString("Test pixel is null (black) when it should be (%2,%3,%4,%5)")
                            .arg(qRed(refPixel)).arg(qGreen(refPixel)).arg(qBlue(refPixel)).arg(qAlpha(refPixel));
        }

        QTest::qFail(msg.toLatin1(), file, line);
        return false;
    }

    if (redFuzz > maxFuzz || greenFuzz > maxFuzz || blueFuzz > maxFuzz || alphaFuzz > maxFuzz) {
        QString msg;

        if (x >= 0)
            msg = QString("Pixel [%1,%2]: ").arg(x).arg(y);
        else
            msg = QString("Pixel ");

        msg += QString("Max fuzz (%1) exceeded: (%2,%3,%4,%5) vs (%6,%7,%8,%9)")
                      .arg(maxFuzz)
                      .arg(qRed(testPixel)).arg(qGreen(testPixel)).arg(qBlue(testPixel)).arg(qAlpha(testPixel))
                      .arg(qRed(refPixel)).arg(qGreen(refPixel)).arg(qBlue(refPixel)).arg(qAlpha(refPixel));
        QTest::qFail(msg.toLatin1(), file, line);
        return false;
    }
    return true;
}

QPixmap Cell::fadedPixmap(const QPixmap & pixmap)
{
    QImage image = pixmap.toImage();
    for(int y = 0; y < image.height(); y++)
    {
	QRgb * line = (QRgb *)image.scanLine(y);
	for(int x = 0; x < image.width(); x++)
	{
	    QRgb pix = line[x];
	    if(qAlpha(pix) == 255)
	    {
		int g = (255 + 3 * qGreen(pix)) / 4;
		int b = (255 + 3 * qBlue(pix)) / 4;
		int r = (255 + 3 * qRed(pix)) / 4;
		line[x] = qRgb(r, g, b);
	    }
	}
    }
    return QPixmap::fromImage(image);
}

void CloudsBlending::blend( QImage * const bottom, TextureTile const * const top ) const
{
    QImage const * const topImage = top->image();
    Q_ASSERT( topImage );
    Q_ASSERT( bottom->size() == topImage->size() );
    int const width = bottom->width();
    int const height = bottom->height();
    for ( int y = 0; y < height; ++y ) {
        for ( int x = 0; x < width; ++x ) {
            qreal const c = qRed( topImage->pixel( x, y )) / 255.0;
            QRgb const bottomPixel = bottom->pixel( x, y );
            int const bottomRed = qRed( bottomPixel );
            int const bottomGreen = qGreen( bottomPixel );
            int const bottomBlue = qBlue( bottomPixel );
            bottom->setPixel( x, y, qRgb(( int )( bottomRed + ( 255 - bottomRed ) * c ),
                                         ( int )( bottomGreen + ( 255 - bottomGreen ) * c ),
                                         ( int )( bottomBlue + ( 255 - bottomBlue ) * c )));
        }
    }
}

void QImageWidget::setImage(const char *filename)
{
  image.load(filename);
//#ifdef USE_MAEMO 
//  unlink(filename);
//#endif  
  clearMask();
  if(w > 0 && h > 0 && ( w < image.width() || h < image.height() ) )
  {
    //printf("set1: setImage %s xy=%d,%d w=%d h=%d width=%d height=%d\n", filename, 
    //x(), y(), w, h, 
    //                                  image.width(),image.height());
    image = image.scaled(w, h, Qt::KeepAspectRatio);
  }
  else if(w > image.width() || h > image.height())
  {
    //printf("set2: setImage %s xy=%d,%d w=%d h=%d width=%d height=%d\n", filename, 
    //x(),y(),w, h, 
    //                                  image.width(),image.height());
    //qt3 image = image.smoothScale(w,h,Qt::KeepAspectRatio);
    image.scaled(w, h, Qt::KeepAspectRatio, Qt::SmoothTransformation);
  }

  if(strstr(filename,".bmp") != NULL || strstr(filename,".BMP") != NULL)
  { // it may be a bmp with transparent background
    int n = image.numColors();
    for(int icol=0; icol<n; icol++)
    {
      QRgb qcol = image.color(icol);
      if(qRed(qcol) == 1 && qGreen(qcol) == 1 && qBlue(qcol) == 1)
      { // image has transparent background
        //image.setAlphaBuffer(true);
        image.setColor(icol,qRgba(1,1,1,0));
        image.createAlphaMask();
      }
    }
  }
  perhapsSetMask();
  original_image = image.copy();
  repaint();
}

static QImage prepareSurface(QImage img, int w, int h)
{
  img = scaleImage(img, w, h);

  // slightly larger, to accomodate for the reflection
  int hs = h * 2;
  int hofs = h / 3;

  // offscreen buffer: black is sweet
  QImage result(hs, w, QImage::Format_RGB32);  
  result.fill(0);

  // transpose the image, this is to speed-up the rendering
  // because we process one column at a time
  // (and much better and faster to work row-wise, i.e in one scanline)
  for(int x = 0; x < w; x++)
    for(int y = 0; y < h; y++)
      result.setPixel(hofs + y, x, img.pixel(x, y));

  // create the reflection
  int ht = hs - h - hofs;
  int hte = ht;
  for(int x = 0; x < w; x++)
    for(int y = 0; y < ht; y++)
    {
      QRgb color = img.pixel(x, img.height()-y-1);
      int a = qAlpha(color);
      int r = qRed(color)   * a / 256 * (hte - y) / hte * 3/5;
      int g = qGreen(color) * a / 256 * (hte - y) / hte * 3/5;
      int b = qBlue(color)  * a / 256 * (hte - y) / hte * 3/5;
      result.setPixel(h+hofs+y, x, qRgb(r, g, b));
    }

#ifdef PICTUREFLOW_BILINEAR_FILTER
  int hh = BILINEAR_STRETCH_VER*hs;
  int ww = BILINEAR_STRETCH_HOR*w;
  result = scaleImage(result, hh, ww);
#endif

  return result;
}