blendshadow.cpp

某智能手机开发公司imageeditor的开发源码

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

static inline int blendComponent( int v, int av, int s, int as )
{
    return as*s + av*v -(av*as*s)/255;  
}
    
static inline QRgb blendShade( QRgb v, QRgb s )
{
    //shadow image is already reduced and blurred
    int as = qAlpha(s); 
    int av = qAlpha(v);
    if ( as == 0 || av == 255 )
	return v;

    int a = as + av -(as*av)/255;
    
    int r = blendComponent( qRed(v),av, qRed(s), as)/a;
    int g = blendComponent( qGreen(v),av, qGreen(s), as)/a;
    int b = blendComponent( qBlue(v),av, qBlue(s), as)/a;

    return qRgba(r,g,b,a);
}

 

//int main( int*, char**)
//{
//    QImage image( "out.png" );
//    image.convertDepth( 32 );
//    QImage shade( "outshade.png" );
//    shade.convertDepth( 32 );
//    int dx = 10;
//    int dy = 5;
//	
//    int w = image.width();
//    int h = image.height();
//	
//    QImage img( w+dx, h+dy, 32 );
//    img.setAlphaBuffer( TRUE );
//
//    for ( int y = 0; y < h+dy; y++ ) {
//	for ( int x = 0; x < w+dx; x++ ) {
//	    QRgb sh =  (x<dx||y<dy) ? 0 : shade.pixel( x-dx, y-dy );
//	    QRgb pixel = (x<w&y<h) ? image.pixel( x, y ) : 0;
//	    img.setPixel( x, y, blendShade( pixel, sh ) ); 
//	}
//    }
//    img.save("blend.png", "PNG" );
//}