examples/graphicsview/portedcanvas/makeimg.cpp
changeset 0 1918ee327afb
child 4 3b1da2848fc7
equal deleted inserted replaced
-1:000000000000 0:1918ee327afb
       
     1 /****************************************************************************
       
     2 **
       
     3 ** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
       
     4 ** All rights reserved.
       
     5 ** Contact: Nokia Corporation (qt-info@nokia.com)
       
     6 **
       
     7 ** This file is part of the examples of the Qt Toolkit.
       
     8 **
       
     9 ** $QT_BEGIN_LICENSE:LGPL$
       
    10 ** No Commercial Usage
       
    11 ** This file contains pre-release code and may not be distributed.
       
    12 ** You may use this file in accordance with the terms and conditions
       
    13 ** contained in the Technology Preview License Agreement accompanying
       
    14 ** this package.
       
    15 **
       
    16 ** GNU Lesser General Public License Usage
       
    17 ** Alternatively, this file may be used under the terms of the GNU Lesser
       
    18 ** General Public License version 2.1 as published by the Free Software
       
    19 ** Foundation and appearing in the file LICENSE.LGPL included in the
       
    20 ** packaging of this file.  Please review the following information to
       
    21 ** ensure the GNU Lesser General Public License version 2.1 requirements
       
    22 ** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
       
    23 **
       
    24 ** In addition, as a special exception, Nokia gives you certain additional
       
    25 ** rights.  These rights are described in the Nokia Qt LGPL Exception
       
    26 ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
       
    27 **
       
    28 ** If you have questions regarding the use of this file, please contact
       
    29 ** Nokia at qt-info@nokia.com.
       
    30 **
       
    31 **
       
    32 **
       
    33 **
       
    34 **
       
    35 **
       
    36 **
       
    37 **
       
    38 ** $QT_END_LICENSE$
       
    39 **
       
    40 ****************************************************************************/
       
    41 
       
    42 #include <qimage.h>
       
    43 #include <qcolor.h>
       
    44 
       
    45 static inline int blendComponent( int v, int av, int s, int as )
       
    46 {
       
    47     //shadow gets a color inversely proportional to the
       
    48     //alpha value
       
    49     s = (s*(255-as))/255;
       
    50     //then do standard blending
       
    51     return as*s + av*v -(av*as*s)/255;  
       
    52 }
       
    53     
       
    54 static inline QRgb blendShade( QRgb v, QRgb s )
       
    55 {
       
    56     //pick a number: shadow is 1/3 of object
       
    57     int as = qAlpha(s)/3; 
       
    58     int av = qAlpha(v);
       
    59     if ( as == 0 || av == 255 )
       
    60 	return v;
       
    61 
       
    62     int a = as + av -(as*av)/255;
       
    63 
       
    64     
       
    65     int r = blendComponent( qRed(v),av, qRed(s), as)/a;
       
    66     int g = blendComponent( qGreen(v),av, qGreen(s), as)/a;
       
    67     int b = blendComponent( qBlue(v),av, qBlue(s), as)/a;
       
    68 
       
    69     return qRgba(r,g,b,a);
       
    70 }
       
    71 
       
    72 int main( int*, char**)
       
    73 {
       
    74     QImage *img;
       
    75 
       
    76     img = new QImage( "in.png" );
       
    77     int w,h;
       
    78     int y;
       
    79     img->setAlphaBuffer( TRUE );
       
    80     *img = img->convertDepth( 32 );
       
    81     w = img->width();
       
    82     h = img->height();
       
    83 #if 0
       
    84     for ( y = 0; y < h; y ++ ) {
       
    85 	uint *line = (uint*)img->scanLine( y );
       
    86 	for ( int x = 0; x < w; x++ ) {
       
    87 	    uint pixel = line[x];
       
    88 	    int r = qRed(pixel);
       
    89 	    int g = qGreen(pixel);
       
    90 	    int b = qBlue(pixel);
       
    91 	    int min = QMIN( r, QMIN( g, b ) );
       
    92 	    int max = QMAX( r, QMAX( g, b ) );
       
    93 	    r -= min;
       
    94 	    g -= min;
       
    95 	    b -= min;
       
    96 	    if ( max !=min ) {
       
    97 		r = (r*255)/(max-min);
       
    98 		g = (g*255)/(max-min);
       
    99 		b = (b*255)/(max-min);
       
   100 	    }
       
   101 	    int a = 255-min;
       
   102 	    a -=  (max-min)/3; //hack more transparency for colors.
       
   103 	    line[x] = qRgba( r, g, b, a );
       
   104 	}
       
   105     }
       
   106 #endif    
       
   107     *img = img->smoothScale( w/2, h/2 );
       
   108 
       
   109     qDebug( "saving out.png");
       
   110     img->save( "out.png", "PNG" );
       
   111     
       
   112     w = img->width();
       
   113     h = img->height();
       
   114     
       
   115     QImage *img2 = new QImage( w, h, 32 );
       
   116     img2->setAlphaBuffer( TRUE );
       
   117     for ( y = 0; y < h; y++ ) {
       
   118 	for ( int x = 0; x < w; x++ ) {
       
   119 	    QRgb shader = img->pixel( x, y );
       
   120 
       
   121 	    int as = qAlpha(shader)/3;
       
   122 
       
   123 	    int r = (qRed(shader)*(255-as))/255;
       
   124 	    int g = (qGreen(shader)*(255-as))/255;
       
   125 	    int b = (qBlue(shader)*(255-as))/255;
       
   126 
       
   127 	    img2->setPixel( x, y, qRgba(r,g,b,as) ); 
       
   128 	}
       
   129     }
       
   130 
       
   131     img2->save( "outshade.png", "PNG" );
       
   132 
       
   133 }