the algo to calculate the color of a wavelength

svn path=/trunk/KDE/kdeedu/kalzium/src/spectrum.h; revision=434250

diff --git a/kalzium/src/spectrum.cpp b/kalzium/src/spectrum.cpp
index 60f5d8c452a4192dbef4d89e6df0a6311faee8b3..b30bde1fe7a1945fc060a51c9d71363cafd0a97c 100644 (file)
--- a/kalzium/src/spectrum.cpp
+++ b/kalzium/src/spectrum.cpp
@@ -22,9 +22,18 @@
 #include <kglobal.h>
 #include <kstandarddirs.h>
 
+#include <math.h>
+
+const double Gamma = 0.80;
+const int IntensityMax = 255;
+
 SpectrumWidget::SpectrumWidget( QWidget* parent, const char* name )
        : QWidget( parent,name )
 {
+       //For the colorcalculation
+       Gamma = 0.8;
+       IntensityMax = 255,
+       
        startValue = 450;
        endValue = 700;
 
@@ -47,11 +56,11 @@ void SpectrumWidget::paintEvent( QPaintEvent * /*e*/ )
        p.begin( this );
        p.fillRect( 0, 0, width(), height(), paletteBackgroundColor() ); 
        p.drawRect( 0,0, width(), height() );
-       QImage i = ref_image;
-       QPixmap px;
-       px.convertFromImage( i.smoothScale( width(), height() ) );
-       m_stretch = ( width() * 1.0 ) / ref_image.width();
-       bitBlt( this, 0, 0, &px );
+//X    QImage i = ref_image;
+//X    QPixmap px;
+//X    px.convertFromImage( i.smoothScale( width(), height() ) );
+//X    m_stretch = ( width() * 1.0 ) / ref_image.width();
+//X    bitBlt( this, 0, 0, &px );
        drawLines(  &p );
 }
 
@@ -69,15 +78,6 @@ void SpectrumWidget::drawLines( QPainter *p )
        //(255,231,49) is for 600 nm
        //(246,144,49) is for 650 nm
        
-/*
-       for(int h = 450; h < 760 ; ++h)
-       {
-               p->setPen(linecolor(h) );
-               p->drawLine(h-450,0,h-450,m_realHeight );
-       }
-               
-       p->setPen(Qt::black);
-*/
 
        int i = 0;
        for ( QValueList<double>::Iterator it = m_spectra.begin();
@@ -91,10 +91,11 @@ void SpectrumWidget::drawLines( QPainter *p )
                
                int temp = 0; // every second item will have a little offset
                if ( i%2 )
-                       temp = 15;
+                       temp = 55;
                else
                        temp = 0;
                
+               p->setPen(linecolor( *it ));
                p->drawLine( x,0,x, m_realHeight+10+temp );
                p->save();
                p->translate(x, m_realHeight+10+15+temp);
@@ -106,6 +107,75 @@ void SpectrumWidget::drawLines( QPainter *p )
        }
 }
 
+void SpectrumWidget::wavelengthToRGB( double wavelength, int& r, int& g, int& b )
+{
+       double blue, green, red, factor;
+
+       if ( wavelength > 380 && wavelength < 439 )
+       {
+               red = -( wavelength-440 ) / ( 440-380 );
+               green = 0.0;
+               blue = 1.0;
+               kdDebug() << "RGB on wavelength 1" << wavelength << ": " << red << " :: " << green << " :: " << blue << " Factor: " << factor << endl;
+       
+       }
+       if ( wavelength > 440 && wavelength < 489 )
+       {
+               red = 0.0;
+               green = -( wavelength-440 ) / ( 490-440 );
+               blue = 1.0;
+               kdDebug() << "RGB on wavelength 2" << wavelength << ": " << red << " :: " << green << " :: " << blue << " Factor: " << factor << endl;
+       }
+       if ( wavelength > 490 && wavelength < 509 )
+       {
+               red = 0.0;
+               green = 1.0;
+               blue = -( wavelength-510 ) / ( 510-490 );
+               kdDebug() << "RGB on wavelength 3" << wavelength << ": " << red << " :: " << green << " :: " << blue << " Factor: " << factor << endl;
+       }
+       if ( wavelength > 510 && wavelength < 579 )
+       {
+               red = -( wavelength-510 ) / ( 580-510 );
+               green = 1.0;
+               blue = 0.0;
+               kdDebug() << "RGB on wavelength 4" << wavelength << ": " << red << " :: " << green << " :: " << blue << " Factor: " << factor << endl;
+       }
+       if ( wavelength > 580 && wavelength < 644 )
+       {
+               red = 1.0;
+               green = -( wavelength-645 ) / ( 645-580 );
+               blue = 0.0;
+               kdDebug() << "RGB on wavelength 5" << wavelength << ": " << red << " :: " << green << " :: " << blue << " Factor: " << factor << endl;
+       }
+       if ( wavelength > 645 && wavelength < 780 )
+       {
+               red = 1.0;
+               green = 0.0;
+               blue = 0.0;
+               kdDebug() << "RGB on wavelength 6" << wavelength << ": " << red << " :: " << green << " :: " << blue << " Factor: " << factor << endl;
+       }
+       if ( wavelength > 380 && wavelength < 419 )
+               factor = 0.3 + 0.7*( wavelength - 380 ) / ( 420 - 380 );
+       else if ( wavelength > 420 && wavelength < 700 )
+               factor = 1.0;
+       else if ( wavelength > 701 && wavelength < 780 )
+               factor = 0.3 + 0.7*( 780 - wavelength ) / ( 780 - 700 );
+       else
+               factor = 0.0;
+
+       r = Adjust( red, factor );
+       g = Adjust( green, factor );
+       b = Adjust( blue, factor );
+}
+
+int SpectrumWidget::Adjust( double color, double factor )
+{
+       if ( color == 0.0 )
+               return 0;
+       else
+               return round( IntensityMax * pow( color*factor, Gamma ) );
+}
+
 int SpectrumWidget::xPos( double value )
 {
 /*
@@ -120,18 +190,10 @@ int SpectrumWidget::xPos( double value )
 
 QColor SpectrumWidget::linecolor( double spectrum )
 {
-//The picture has 575 pixel
-//
-
-       //Example: Freq is 600nm. 760-450 = 360.
-       //760 - 600 = 160.   360/160 = 2.25
-       int proportion = m_stretch * ( spectrum - startValue ) / ( endValue - startValue );
-
-       QRgb rgb = ref_image.pixel(proportion, 2 );
-
-       kdDebug() << "RGB: " << rgb << " Prop " << proportion << endl;
+       int r,g,b;
+       wavelengthToRGB( spectrum, r,g,b );
        
-       QColor c( rgb );
+       QColor c( r,g,b );
        return c;
 }
 

diff --git a/kalzium/src/spectrum.h b/kalzium/src/spectrum.h
index b22ee5210b5f00c24db21713a0203afd7fa83152..1a24a746c54f1566c267b9cc42aa41a58183361d 100644 (file)
--- a/kalzium/src/spectrum.h
+++ b/kalzium/src/spectrum.h
@@ -51,6 +51,13 @@ class SpectrumWidget : public QWidget
 
                QImage ref_image;
 
+               int Adjust( double color, double factor );
+
+               void wavelengthToRGB( double wavelength, int& r, int& g, int& b );
+
+               double Gamma;
+               int IntensityMax;
+
                /**
                 * draws the spectra-lines
                 */