// Licence: wxWindows licence
/////////////////////////////////////////////////////////////////////////////
+//// TODO: make wxColour a ref-counted object,
+//// so pixel values get shared.
+
#ifdef __GNUG__
#pragma implementation "colour.h"
#endif
#include "wx/gdicmn.h"
#include "wx/colour.h"
+#include "wx/app.h"
+
+#include <Xm/Xm.h>
+
+#include "wx/motif/private.h"
#if !USE_SHARED_LIBRARY
IMPLEMENT_DYNAMIC_CLASS(wxColour, wxObject)
{
m_isInit = FALSE;
m_red = m_blue = m_green = 0;
-/* TODO
- m_pixel = 0;
-*/
+ m_pixel = -1;
}
wxColour::wxColour (unsigned char r, unsigned char g, unsigned char b)
m_green = g;
m_blue = b;
m_isInit = TRUE;
-/* TODO
- m_pixel = PALETTERGB (m_red, m_green, m_blue);
-*/
+ m_pixel = -1;
}
wxColour::wxColour (const wxColour& col)
m_green = col.m_green;
m_blue = col.m_blue;
m_isInit = col.m_isInit;
-/* TODO
m_pixel = col.m_pixel;
-*/
}
wxColour& wxColour::operator =(const wxColour& col)
m_green = col.m_green;
m_blue = col.m_blue;
m_isInit = col.m_isInit;
-/* TODO
m_pixel = col.m_pixel;
-*/
return *this;
}
m_red = the_colour->Red ();
m_green = the_colour->Green ();
m_blue = the_colour->Blue ();
+ m_pixel = the_colour->m_pixel;
m_isInit = TRUE;
}
else
m_blue = 0;
m_isInit = FALSE;
}
-/* TODO
- m_pixel = PALETTERGB (m_red, m_green, m_blue);
-*/
}
wxColour::~wxColour ()
m_red = the_colour->Red ();
m_green = the_colour->Green ();
m_blue = the_colour->Blue ();
+ m_pixel = the_colour->m_pixel;
m_isInit = TRUE;
}
else
m_blue = 0;
m_isInit = FALSE;
}
-/* TODO
- m_pixel = PALETTERGB (m_red, m_green, m_blue);
-*/
+
return (*this);
}
m_green = g;
m_blue = b;
m_isInit = TRUE;
-/* TODO
- m_pixel = PALETTERGB (m_red, m_green, m_blue);
-*/
+ m_pixel = -1;
+}
+
+// Allocate a colour, or nearest colour, using the given display.
+// If realloc is TRUE, ignore the existing pixel, otherwise just return
+// the existing one.
+// Returns the old or allocated pixel.
+
+// TODO: can this handle mono displays? If not, we should have an extra
+// flag to specify whether this should be black or white by default.
+
+int wxColour::AllocColour(WXDisplay* display, bool realloc)
+{
+ if ((m_pixel != -1) && !realloc)
+ return m_pixel;
+
+ XColor color;
+ color.red = (unsigned short) Red ();
+ color.red |= color.red << 8;
+ color.green = (unsigned short) Green ();
+ color.green |= color.green << 8;
+ color.blue = (unsigned short) Blue ();
+ color.blue |= color.blue << 8;
+
+ color.flags = DoRed | DoGreen | DoBlue;
+
+ WXColormap cmap = wxTheApp->GetMainColormap(display);
+
+ if (!XAllocColor ((Display*) display, (Colormap) cmap, &color))
+ {
+ m_pixel = wxGetBestMatchingPixel((Display*) display, &color,(Colormap) cmap);
+ return m_pixel;
+ }
+ else
+ {
+ m_pixel = (int) color.pixel;
+ return m_pixel;
+ }
+}
+
+/*-------------------------------------------
+Markus Emmenegger <mege@iqe.ethz.ch>
+Find the pixel value with an assigned color closest to the desired color
+Used if color cell allocation fails
+As the returned pixel value may be in use by another application,
+the color might change anytime.
+But in many cases, that is still better than always using black.
+--
+Chris Breeze <chris@hel.co.uk>
+Improvements:
+1) More efficient calculation of RGB distance of colour cell from
+ the desired colour. There is no need to take the sqrt of 'dist', and
+ since we are only interested in the top 8-bits of R, G and B we
+ can perform integer arithmetic.
+2) Attempt to allocate a read-only colour when a close match is found.
+ A read-only colour will not change.
+3) Fall back to the closest match if no read-only colours are available.
+
+Possible further improvements:
+1) Scan the lookup table and sort the colour cells in order of
+increasing
+ distance from the desired colour. Then attempt to allocate a
+read-only
+ colour starting from the nearest match.
+2) Linear RGB distance is not a particularly good method of colour
+matching
+ (though it is quick). Converting the colour to HLS and then comparing
+ may give better matching.
+-------------------------------------------*/
+
+int wxGetBestMatchingPixel(Display *display, XColor *desiredColor, Colormap cmap)
+{
+ if (cmap == (Colormap) NULL)
+ cmap = (Colormap) wxTheApp->GetMainColormap(display);
+
+ int numPixVals = XDisplayCells(display, DefaultScreen (display));
+ int mindist = 256 * 256 * 3;
+ int bestpixel = (int) BlackPixel (display, DefaultScreen (display));
+ int red = desiredColor->red >> 8;
+ int green = desiredColor->green >> 8;
+ int blue = desiredColor->blue >> 8;
+ const int threshold = 2 * 2 * 3; // allow an error of up to 2 in R,G & B
+
+ for (int pixelcount = 0; pixelcount < numPixVals; pixelcount++)
+ {
+ XColor matching_color;
+ matching_color.pixel = pixelcount;
+ XQueryColor(display,cmap,&matching_color);
+
+ int delta_red = red - (matching_color.red >> 8);
+ int delta_green = green - (matching_color.green >> 8);
+ int delta_blue = blue - (matching_color.blue >> 8);
+
+ int dist = delta_red * delta_red +
+ delta_green * delta_green +
+ delta_blue * delta_blue;
+
+ if (dist <= threshold)
+ {
+ // try to allocate a read-only colour...
+ if (XAllocColor (display, cmap, &matching_color))
+ {
+ return matching_color.pixel;
+ }
+ }
+ if (dist < mindist)
+ {
+ bestpixel = pixelcount;
+ mindist = dist;
+ }
+ }
+ return bestpixel;
}
projects / wxWidgets.git / blobdiff