From: pbristow_at_[hidden]
Date: 2007-10-18 12:12:13
Author: pbristow
Date: 2007-10-18 12:12:12 EDT (Thu, 18 Oct 2007)
New Revision: 40157
URL: http://svn.boost.org/trac/boost/changeset/40157
Log:
Added operator<< and changed handling of blank to set default color to white.
blank has yet to be handled by the output code?
Text files modified:
sandbox/SOC/2007/visualization/boost/svg_plot/svg_color.hpp | 106 +++++++++++++++++++++++++++++----------
1 files changed, 79 insertions(+), 27 deletions(-)
Modified: sandbox/SOC/2007/visualization/boost/svg_plot/svg_color.hpp
==============================================================================
--- sandbox/SOC/2007/visualization/boost/svg_plot/svg_color.hpp (original)
+++ sandbox/SOC/2007/visualization/boost/svg_plot/svg_color.hpp 2007-10-18 12:12:12 EDT (Thu, 18 Oct 2007)
@@ -1,15 +1,18 @@
// svg_color.hpp
-// Copyright (C) Jacob Voytko 2007
-//
-// Distributed under the Boost Software License, Version 1.0.
-// For more information, see http://www.boost.org
-// -----------------------------------------------------------------
+// Copyright Jacob Voytko 2007
+// Copyright Paul A. Bristow 2007
+//
+// Use, modification and distribution are subject to the
+// Boost Software License, Version 1.0.
+// (See accompanying file LICENSE_1_0.txt
+// or copy at http://www.boost.org/LICENSE_1_0.txt)
#ifndef BOOST_SVG_SVG_COLOR_HPP
#define BOOST_SVG_SVG_COLOR_HPP
#include <ostream>
+// using std::ostream
namespace boost
{
@@ -51,38 +54,47 @@
salmon, sandybrown, seagreen, seashell, sienna, silver,
skyblue, slateblue, slategray, slategrey, snow, springgreen,
steelblue, tan, teal, thistle, tomato, turquoise, violet,
+ // Forward declarations.
wheat, white, whitesmoke, yellow, yellowgreen, blank
};
+// Forward declarations:
+struct svg_color;
void constant_to_rgb(svg_color_constant _c, unsigned char &r,
unsigned char &g, unsigned char &b);
+std::ostream& operator<< (std::ostream&, const svg_color&);
// -----------------------------------------------------------------
-// svg_color is the struct that contains information about RGB
-// colors.
+// svg_color is the struct that contains information about RGB colors.
//
-// For the constructor: the SVG standard specifies that numbers
+// For the constructor, the SVG standard specifies that numbers
// outside the normal rgb range are to be accepted, but are rounded
// to acceptable values [0, 255].
// -----------------------------------------------------------------
+
struct svg_color
{
+ friend std::ostream& operator<< (std::ostream& os, const svg_color& rhs);
+
unsigned char r, g, b;
- bool blank;
+ bool blank; // true means "Not to be displayed" 'pseudo-color'.
+ // TODO seems to display as black? - Need a check if is_blank == true?
svg_color(int _r, int _g, int _b) : blank(false)
- {
+ { // Constrain rgb to [0 .. 255]
_r = ( _r < 0 ) ? 0 : _r;
_g = ( _g < 0 ) ? 0 : _g;
_b = ( _b < 0 ) ? 0 : _b;
-
r = (unsigned char)(( _r > 255 ) ? 255 : _r);
g = (unsigned char)(( _g > 255 ) ? 255 : _g);
b = (unsigned char)(( _b > 255 ) ? 255 : _b);
}
svg_color(bool _is) : blank(_is)
- {
+ {
+ r = 0; // Safer to assign *some* value to rgb? zero, or 255?
+ g = 0; // rather than leaving random?
+ b = 0;
}
svg_color(svg_color_constant _col) : blank(false)
@@ -97,19 +109,54 @@
rhs << "rgb(" << (unsigned int)r << "," << (unsigned int) g << ","
<< (unsigned int)b << ")" ;
}
-
else
{
- rhs <<"blank";
+ rhs << "blank";
}
- }
+ // Usage: my_color.write(cout); cout << endl; outputs: rgb(127,255,212)
+ } // void write(std::ostream& rhs)
- bool operator==(const svg_color& rhs)
+ bool operator== (const svg_color& rhs)
{
- return r == rhs.r && g == rhs.g && b == rhs.b;
+ if ((blank) || (rhs.blank == true))
+ { // Make blank a sort of NaN, that never compares true?
+ // not even if both rhs and lhs are blank.
+ return false;
+ }
+ return (r == rhs.r) && (g == rhs.g) && (b == rhs.b);
}
}; // struct svg_color
+bool operator== (const svg_color& lhs, const svg_color& rhs)
+{
+ if ((rhs.blank == true) || (rhs.blank == true))
+ { // Make blank a sort of NaN, that never compares true?
+ // not even if both rhs and lhs are blank.
+ return false;
+ }
+ return (lhs.r == rhs.r) && (lhs.g == rhs.g) && (lhs.b == rhs.b);
+}
+
+std::ostream& operator<< (std::ostream& os, const svg_color& color)
+{
+ if(!color.blank)
+ {
+ os << "RGB("
+ << (unsigned int)color.r << ","
+ << (unsigned int) color.g << ","
+ << (unsigned int)color.b << ")" ;
+ }
+ else
+ {
+ os << "blank";
+ }
+ // Usage: svg_color my_color(127, 255, 212); cout << "my_color " << my_color << endl;
+ // Outputs: my_color RGB(127,255,212)
+ // cout << "magenta " << svg_color(magenta) << endl;
+ // but caution cout << magenta << endl; outputs 85 because magenta is an enum!
+ return os;
+} // std::ostream& operator<<
+
svg_color color_array[] =
{
svg_color(240, 248, 255), // aliceblue
@@ -259,19 +306,24 @@
svg_color(245, 245, 245), // whitesmoke
svg_color(255, 255, 0 ), // yellow
svg_color(154, 205, 50 ), // yellowgreen
- svg_color(false) // blank
+ svg_color(false) // blank - "Not to be displayed" pseudo-color.
}; // svg_color color_array[]
-void constant_to_rgb(svg_color_constant _c, unsigned char &r,
- unsigned char &g, unsigned char &b)
-{
- svg_color temp(color_array[_c]);
-
- if(!temp.blank)
+void constant_to_rgb(svg_color_constant _c,
+ unsigned char &r, unsigned char &g, unsigned char &b)
+{ // Convert a named SVG standard color to rgb.
+ svg_color color(color_array[_c]);
+ if(!color.blank)
{
- r = temp.r;
- g = temp.g;
- b = temp.b;
+ r = color.r;
+ g = color.g;
+ b = color.b;
+ }
+ else
+ { // Unwise to leave r, g, & b unchanged?
+ r = 255; // Set all to white?
+ g = 255;
+ b = 255;
}
}