Allow bgcolor to be set to any color, not just string

chaco/api.py

@@ -6,7 +6,7 @@
 from base import NumericalSequenceTrait, PointTrait, ImageTrait, DimensionTrait, \
                  SortOrderTrait, bin_search, reverse_map_1d, right_shift, \
                  left_shift, sort_points, find_runs, arg_find_runs, \
-                 point_line_distance
+                 point_line_distance, colors_equal
 
 # Data model
 from abstract_data_source import AbstractDataSource

chaco/base.py

@@ -221,5 +221,24 @@ def point_line_distance(pt, p1, p2):
 
     return sqrt(dot(diff,diff))
 
+def standardize_color(color):
+    from enable.api import color_table
+    if isinstance(color, basestring):
+        color = color_table[color]
+    color = list(color)
+    if len(color) == 3:
+        color.append(1.0)
+    return tuple(color)
+
+def colors_equal(color1, color2, match_alpha=False):
+    """ Determine whether two colors are equal.  If match_alpha==True,
+    they must have the same alpha value as well. """
+    color1 = standardize_color(color1)
+    color2 = standardize_color(color2)
+    if not match_alpha:
+        color1 = color1[:3]
+        color2 = color2[:3]
+    return color1 == color2
+
 
 #EOF

chaco/data_view.py

@@ -4,8 +4,8 @@
 from numpy import array, transpose
 
 from traits.api import Bool, Enum, Instance, Property
-from enable.colors import color_table
 
+from chaco.api import colors_equal
 from abstract_overlay import AbstractOverlay
 from axis import PlotAxis
 from base_1d_mapper import Base1DMapper
@@ -270,7 +270,7 @@ def _init_components(self):
         # make sure the grid and bgcolor are not the same color
 
         grid_color = 'lightgray'
-        if color_table[self.bgcolor] == color_table[grid_color]:
+        if colors_equal(self.bgcolor, grid_color):
             grid_color = 'white'
 
         if not self.x_grid and self.auto_grid:

chaco/tests/base_utils_test_case.py

@@ -7,7 +7,10 @@
 from numpy import arange, array
 from numpy.testing import assert_equal, assert_almost_equal
 
-from chaco.api import bin_search, find_runs, reverse_map_1d, point_line_distance
+from chaco.api import bin_search, find_runs, reverse_map_1d, point_line_distance, colors_equal
+from enable.api import ColorTrait
+from traits.api import HasTraits
+
 
 class BinSearchTestCase(unittest.TestCase):
     def test_ascending_data(self):
@@ -165,6 +168,46 @@ def test_point_on_line(self):
         assert_almost_equal(dist, 0.0)
 
 
+class SimpleColorTraits(HasTraits):
+    """ A class to hold a ColorTrait for testing """
+    color = ColorTrait
+
+class ColorEqualTestCase(unittest.TestCase):
+
+    def test_strings(self):
+        color = 'blue'
+        inst1 = SimpleColorTraits(color=color)
+        inst2 = SimpleColorTraits(color=color)
+        self.assert_(colors_equal(inst1.color, inst2.color))
+
+    def test_tuples(self):
+        color = (0, 1, 0)
+        inst1 = SimpleColorTraits(color=color)
+        inst2 = SimpleColorTraits(color=color)
+        self.assert_(colors_equal(inst1.color, inst2.color))
+
+    def test_string_tuple(self):
+        color1 = 'red'
+        color2 = (1, 0, 0)
+        inst1 = SimpleColorTraits(color=color1)
+        inst2 = SimpleColorTraits(color=color2)
+        self.assert_(colors_equal(inst1.color, inst2.color))
+
+    def test_tuples_different_length(self):
+        color1 = (0, 1, 0)
+        color2 = (0, 1, 0, 1)
+        inst1 = SimpleColorTraits(color=color1)
+        inst2 = SimpleColorTraits(color=color2)
+        self.assert_(colors_equal(inst1.color, inst2.color))
+
+    def test_alpha(self):
+        color1 = (0, 1, 0, 1.0)
+        color2 = (0, 1, 0, 0.5)
+        inst1 = SimpleColorTraits(color=color1)
+        inst2 = SimpleColorTraits(color=color2)
+        self.assertTrue(colors_equal(inst1.color, inst2.color, match_alpha=False))
+        self.assertFalse(colors_equal(inst1.color, inst2.color, match_alpha=True))
+
+
 if __name__ == '__main__':
-    import nose
-    nose.run()
+    unittest.main()

chaco/tests/data_view_test_case.py

@@ -16,6 +16,23 @@ def test_empty(self):
         self.assert_(dv.range2d.x_range==dv.index_range)
         self.assert_(dv.range2d.y_range==dv.value_range)
 
+    def test_bgcolor(self):
+        """ Test setting background color """
+        color = 'blue'
+        dv = DataView(bgcolor=color)
+        self.assertEqual(dv.bgcolor, color)
+        color = (0,0,0,0)
+        dv = DataView(bgcolor=color)
+        self.assertEqual(dv.bgcolor, color)
+
+    def test_bg_gridcolor(self):
+        """Test setting background to grid color"""
+        for color in ['lightgray', 'lightgray',
+                      (0.827, 0.827, 0.827), (0.827, 0.827, 0.827, 1.0)]:
+            dv = DataView(bgcolor=color)
+            self.assertEqual(dv.bgcolor, color)
+            self.assertEqual(dv.x_grid.line_color, 'white')
+
     def test_orientation(self):
         dv = DataView()
         x_mapper_start = dv.x_mapper

chaco/tests/plot_test_case.py

@@ -0,0 +1,31 @@
+import unittest
+
+from chaco.api import Plot
+
+
+class PlotTestCase(unittest.TestCase):
+
+    def test_empty(self):
+        plot = Plot()
+        self.assertEqual(plot.orientation, "h")
+        self.assertEqual(plot.index_scale, "linear")
+        self.assertEqual(plot.bgcolor, "white")
+        self.assertEqual(plot.overlay_border, True)
+
+        self.assertEqual(plot.range2d.x_range, plot.index_range)
+        self.assertEqual(plot.range2d.y_range, plot.value_range)
+        self.assertEqual(plot.bgcolor, "white")
+
+    def test_bgcolor(self):
+        """ Test setting background color """
+        color = 'blue'
+        plot = Plot(bgcolor=color)
+        self.assertEqual(plot.bgcolor, color)
+        color = (0,0,0,0)
+        plot = Plot(bgcolor=color)
+        self.assertEqual(plot.bgcolor, color)
+
+
+if __name__ == '__main__':
+    unittest.main()
+