axes color order ?

[John W. Eaton]

On  5-Oct-2007, Schirmacher, Rolf wrote:

| I want to define a certain color order for the lines coming up in a plot,
| i.e. some special colors instead of the standard of blue, green, red, ...
| 
| In octave 2.9.13, the colors are defined by the color_rotation array in the
| __next_line_color__.m function of the plot package. Whenever a new axes is
| created, the color_index is reset and the persistent variable color_rotation
| is refreshed with the fixed default values. So it seems like supplying
| different values in this function should do what I want... color handling
| like choosing the next and using it for the plot is completely implemented
| ... fine!
| 
| Now, at the other program, there seems to be a "ColorOrder" property of an
| axes and this defines the array of rgb values in the way as it could
| directly be used in __next_line_color__.m instead of the default
| color_rotation there. In addition, a figure has a "DefaultAxesColorOrder"
| property which is inherited by default by all axes within the figure and the
| root figure (handle 0) also has such a property which is by default
| inherited by all figures, so setting the "DefaultAxesColorOrder" for handle
| 0 makes all figures appear with the customised color orders.
| 
| These properties are currently not implemented in octave.
| 
| My question is: Is there any simple, "user space" (i.e. m-files only) way to
| add an additional property to a graphics object? Then I could easily add the
| properties and their handling to the existing code. Actually I did not find
| such a possibility nor did I find any hint in the documentation (get/set
| seem to work for predefined properties only...)

No, currently properties can only be added in the C++ classes that
implement the graphics properties in Octave.  It is not terribly
difficult to do this.  How about the following patch?  Does it do what
you need?  If not, then I encourage you to submit a patch that makes
this new property behave correctly.

Thanks,

jwe


scripts/ChangeLog:

2007-10-05  John W. Eaton  <address@hidden>

        * plot/__next_line_color__.m: Get color_rotation from axes
        colororder property.


src/ChangeLog:

2007-10-05  John W. Eaton  <address@hidden>

        * graphics.h.in (axes::properties): New property, colororder.
        * graphics.cc (default_colororder): New function.
        (axes::properties::properties, axes::properties::get,
        axes::properties::set_defaults,
        axes::properties::factory_defaults, ): Handle colororder.


Index: scripts/plot/__next_line_color__.m
===================================================================
RCS file: /cvs/octave/scripts/plot/__next_line_color__.m,v
retrieving revision 1.3
diff -u -u -r1.3 __next_line_color__.m
--- scripts/plot/__next_line_color__.m  13 Sep 2007 18:22:38 -0000      1.3
+++ scripts/plot/__next_line_color__.m  5 Oct 2007 20:48:51 -0000
@@ -25,25 +25,22 @@
 
 function rgb = __next_line_color__ (reset)
 
-  persistent color_rotation = [ 0,    0,    1;
-                               0,    0.5,  0;
-                               1,    0,    0;
-                               0,    0.75, 0.75;
-                               0.75, 0,    0.75;
-                               0.75, 0.75, 0;
-                               0.25, 0.25, 0.25];
-
-  persistent num_colors = rows (color_rotation);
-  persistent color_index = 1;
+  persistent color_rotation;
+  persistent num_colors;
+  persistent color_index;
 
   if (nargin < 2)
     if (nargin == 1 && reset)
+      color_rotation = get (gca (), "colororder");
+      num_colors = rows (color_rotation);
       color_index = 1;
-    else
+    elseif (! isempty (color_rotation))
       rgb = color_rotation(color_index,:);
       if (++color_index > num_colors)
        color_index = 1;
       endif
+    else
+      error ("__next_line_color__: color_rotation not initialized");
     endif
   else
     print_usage ();
Index: src/graphics.cc
===================================================================
RCS file: /cvs/octave/src/graphics.cc,v
retrieving revision 1.37
diff -u -u -r1.37 graphics.cc
--- src/graphics.cc     2 Oct 2007 20:47:22 -0000       1.37
+++ src/graphics.cc     5 Oct 2007 20:48:55 -0000
@@ -1001,6 +1001,33 @@
 
 // ---------------------------------------------------------------------
 
+static Matrix
+default_colororder (void)
+{
+  Matrix retval (7, 3, 0.0);
+
+  retval(0,2) = 1.0;
+
+  retval(1,1) = 0.5;
+
+  retval(2,0) = 1.0;
+
+  retval(3,1) = 0.75;
+  retval(3,2) = 0.75;
+
+  retval(4,0) = 0.75;
+  retval(4,2) = 0.75;
+
+  retval(5,0) = 0.75;
+  retval(5,1) = 0.75;
+
+  retval(6,0) = 0.25;
+  retval(6,1) = 0.25;
+  retval(6,2) = 0.25;
+
+  return retval;
+}
+
 axes::properties::properties (const graphics_handle& mh,
                                        const graphics_handle& p)
   : base_properties (go_name, mh, p),
@@ -1010,6 +1037,7 @@
     key ("off"),
     keybox ("off"),
     keypos (1),
+    colororder (default_colororder ()),
     dataaspectratio (Matrix (1, 3, 1.0)),
     dataaspectratiomode ("auto"),
     xlim (),
@@ -1163,6 +1191,8 @@
     set_keybox (val);
   else if (name.compare ("keypos"))
     set_keypos (val);
+  else if (name.compare ("colororder"))
+    set_colororder (val);
   else if (name.compare ("dataaspectratio"))
     set_dataaspectratio (val);
   else if (name.compare ("dataaspectratiomode"))
@@ -1269,6 +1299,7 @@
   key = "off";
   keybox = "off";
   keypos = 1;
+  colororder = default_colororder ();
   dataaspectratio = Matrix (1, 3, 1.0);
   dataaspectratiomode = "auto";
 
@@ -1392,6 +1423,7 @@
   m.assign ("key", key);
   m.assign ("keybox", keybox);
   m.assign ("keypos", keypos);
+  m.assign ("colororder", colororder);
   m.assign ("dataaspectratio", dataaspectratio);
   m.assign ("dataaspectratiomode", dataaspectratiomode);
   m.assign ("xlim", xlim);
@@ -1464,6 +1496,8 @@
     retval = keybox;
   else if (name.compare ("keypos"))
     retval = keypos;
+  else if (name.compare ("colororder"))
+    retval = colororder;
   else if (name.compare ("dataaspectratio"))
     retval = dataaspectratio;
   else if (name.compare ("dataaspectratiomode"))
@@ -1593,6 +1627,7 @@
   m["key"] = "off";
   m["keybox"] = "off";
   m["keypos"] = 1;
+  m["colororder"] = default_colororder ();
   m["dataaspectratio"] = Matrix (1, 3, 1.0);
   m["dataaspectratiomode"] = "auto";
 
Index: src/graphics.h.in
===================================================================
RCS file: /cvs/octave/src/graphics.h.in,v
retrieving revision 1.7
diff -u -u -r1.7 graphics.h.in
--- src/graphics.h.in   1 Oct 2007 15:59:33 -0000       1.7
+++ src/graphics.h.in   5 Oct 2007 20:48:55 -0000
@@ -1136,6 +1136,7 @@
       octave_value key
       octave_value keybox
       octave_value keypos
+      octave_value colororder
       octave_value dataaspectratio m
       octave_value dataaspectratiomode
       octave_value xlim m