1 files changed, 92 insertions, 0 deletions
diff --git a/libXmu/src/Distinct.c b/libXmu/src/Distinct.c
new file mode 100644
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+++ b/libXmu/src/Distinct.c
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+/* $Xorg: Distinct.c,v 1.4 2001/02/09 02:03:52 xorgcvs Exp $ */
+
+/*
+
+Copyright 1990, 1998  The Open Group
+
+Permission to use, copy, modify, distribute, and sell this software and its
+documentation for any purpose is hereby granted without fee, provided that
+the above copyright notice appear in all copies and that both that
+copyright notice and this permission notice appear in supporting
+documentation.
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+Except as contained in this notice, the name of The Open Group shall not be
+used in advertising or otherwise to promote the sale, use or other dealings
+in this Software without prior written authorization from The Open Group.
+
+*/
+/* $XFree86: xc/lib/Xmu/Distinct.c,v 3.5 2001/07/25 15:04:50 dawes Exp $ */
+
+/*
+ * Author:  Keith Packard, MIT X Consortium
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+#include <X11/Xlib.h>
+#include <stdlib.h>
+#include <X11/Xutil.h>
+#include <X11/Xmu/StdCmap.h>
+
+/*
+ * Distinguishable colors routine.  Determines if two colors are
+ * distinguishable or not.  Somewhat arbitrary meaning.
+ */
+
+#define MIN_DISTINGUISH	10000.0
+
+Bool
+XmuDistinguishableColors(XColor	*colors, int count)
+{
+    double	    deltaRed, deltaGreen, deltaBlue;
+    double	    dist;
+    int		    i, j;
+
+    for (i = 0; i < count - 1; i++)
+	for (j = i + 1; j < count; j++)
+	{
+     	    deltaRed = (double)colors[i].red - (double)colors[j].red;
+    	    deltaGreen = (double)colors[i].green - (double)colors[j].green;
+    	    deltaBlue = (double)colors[i].blue - (double)colors[j].blue;
+    	    dist = deltaRed * deltaRed +
+	       	   deltaGreen * deltaGreen +
+ 	       	   deltaBlue * deltaBlue;
+	    if (dist <= MIN_DISTINGUISH * MIN_DISTINGUISH)
+		return False;
+	}
+    return True;
+}
+
+Bool
+XmuDistinguishablePixels(Display *dpy, Colormap cmap,
+			 unsigned long *pixels, int  count)
+{
+    XColor  *defs;
+    int	    i, j;
+    Bool    ret;
+
+    for (i = 0; i < count - 1; i++)
+	for (j = i + 1; j < count; j++)
+	    if (pixels[i] == pixels[j])
+		return False;
+    defs = (XColor *) malloc (count * sizeof (XColor));
+    if (!defs)
+	return False;
+    for (i = 0; i < count; i++)
+	defs[i].pixel = pixels[i];
+    XQueryColors (dpy, cmap, defs, count);
+    ret = XmuDistinguishableColors (defs, count);
+    free ((char *) defs);
+    return ret;
+}