From 72ca81b31e7259d315f4a6b0af6d6eeb82e7ac28 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Wed, 14 Sep 2016 00:33:37 +0100
Subject: [PATCH 01/21] Implemented ColorbarPlot and LegendPlot baseclasses in
 bokeh

---
 holoviews/plotting/bokeh/element.py | 141 +++++++++++++++++++++++-----
 1 file changed, 120 insertions(+), 21 deletions(-)

diff --git a/holoviews/plotting/bokeh/element.py b/holoviews/plotting/bokeh/element.py
index 1493fc7997..4e65648ca9 100644
--- a/holoviews/plotting/bokeh/element.py
+++ b/holoviews/plotting/bokeh/element.py
@@ -7,6 +7,14 @@
 from bokeh.models.tickers import Ticker, BasicTicker, FixedTicker
 from bokeh.models.widgets import Panel, Tabs
 
+from bokeh.models.mappers import LinearColorMapper
+try:
+    from bokeh.models import ColorBar
+    from bokeh.models.mappers import LogColorMapper
+except ImportError:
+    LogColorMapper, ColorBar = None, None
+from bokeh.models import LogTicker, BasicTicker
+
 try:
     from bokeh import mpl
 except ImportError:
@@ -22,7 +30,8 @@
 from ..util import dynamic_update
 from .callbacks import Callbacks
 from .plot import BokehPlot
-from .util import mpl_to_bokeh, convert_datetime, update_plot, bokeh_version
+from .util import (mpl_to_bokeh, convert_datetime, update_plot,
+                   bokeh_version, mplcmap_to_palette)
 
 if bokeh_version >= '0.12':
     from bokeh.models import FuncTickFormatter
@@ -618,6 +627,115 @@ def framewise(self):
                    for frame in current_frames)
 
 
+
+class ColorbarPlot(ElementPlot):
+
+    colorbar = param.Boolean(default=False, doc="""
+        Whether to display a colorbar.""")
+
+    colorbar_position = param.ObjectSelector(objects=["top_right",
+                                                      "top_left",
+                                                      "bottom_left",
+                                                      "bottom_right",
+                                                      'right', 'left',
+                                                      'top', 'bottom'],
+                                             default="right",
+                                             doc="""
+        Allows selecting between a number of predefined colorbar position
+        options. The predefined options may be customized in the
+        colorbar_specs class attribute.""")
+
+    colorbar_opts = param.Dict(default={}, doc="""
+        Allows setting specific styling options for the colorbar overriding
+        the options defined in the colorbar_specs class attribute. Includes
+        location, orientation, height, width, scale_alpha, title, title_props,
+        margin, padding, background_fill_color and more.""")
+
+    colorbar_specs = {'right': {'pos': 'right', 'opts': {'location': (0, 0)}},
+                      'left': {'pos': 'left', 'opts':{'location':(0, 0)}},
+                      'top_right': {'pos': 'center', 'opts': {'location': 'top_right'}},
+                      'top_left': {'pos': 'center', 'opts': {'location': 'top_left'}},
+                      'top': {'opts': {'location':(0, 0), 'orientation':'horizontal'},
+                              'pos': 'above'},
+                      'bottom': {'opts': {'location': (0, 0), 'orientation':'horizontal'},
+                                 'pos': 'below'},
+                      'bottom_left': {'pos': 'center',
+                                      'opts': {'location': 'bottom_center',
+                                               'orientation': 'horizontal'}},
+                      'bottom_right': {'pos': 'center',
+                                      'opts': {'location': 'bottom_right',
+                                               'orientation': 'horizontal'}}}
+
+    logz  = param.Boolean(default=False, doc="""
+         Whether to apply log scaling to the z-axis.""")
+
+    def _draw_colorbar(self, plot, color_mapper):
+        if LogColorMapper and isinstance(color_mapper, LogColorMapper):
+            ticker = LogTicker()
+        else:
+            ticker = BasicTicker()
+        cbar_opts = self.colorbar_specs[self.colorbar_position]
+
+        # Check if there is a colorbar in the same position
+        pos = cbar_opts['pos']
+        if any(isinstance(model, ColorBar) for model in getattr(plot, pos, [])):
+            return
+
+        color_bar = ColorBar(color_mapper=color_mapper, ticker=ticker,
+                             **dict(cbar_opts['opts'], **self.colorbar_opts))
+
+        plot.add_layout(color_bar, pos)
+        self.handles['colorbar'] = color_bar
+
+
+    def _get_colormapper(self, dim, element, ranges, style):
+        low, high = ranges.get(dim.name)
+        if 'cmap' in style:
+            palette = mplcmap_to_palette(style.pop('cmap', None))
+        colormapper = LogColorMapper if self.logz else LinearColorMapper
+        cmapper = colormapper(palette, low=low, high=high)
+        if 'color_mapper' not in self.handles:
+            self.handles['color_mapper'] = cmapper
+        return cmapper
+
+
+    def _init_glyph(self, plot, mapping, properties):
+        """
+        Returns a Bokeh glyph object and optionally creates a colorbar.
+        """
+        ret = super(ColorbarPlot, self)._init_glyph(plot, mapping, properties)
+        if self.colorbar and 'color_mapper' in self.handles:
+            self._draw_colorbar(plot, self.handles['color_mapper'])
+        return ret
+
+
+
+class LegendPlot(ElementPlot):
+
+    legend_position = param.ObjectSelector(objects=["top_right",
+                                                    "top_left",
+                                                    "bottom_left",
+                                                    "bottom_right",
+                                                    'right', 'left',
+                                                    'top', 'bottom'],
+                                                    default="top_right",
+                                                    doc="""
+        Allows selecting between a number of predefined legend position
+        options. The predefined options may be customized in the
+        legend_specs class attribute.""")
+
+
+    legend_cols = param.Integer(default=False, doc="""
+       Whether to lay out the legend as columns.""")
+
+
+    legend_specs = {'right': dict(pos='right', loc=(5, -40)),
+                    'left': dict(pos='left', loc=(0, -40)),
+                    'top': dict(pos='above', loc=(120, 5)),
+                    'bottom': dict(pos='below', loc=(60, 0))}
+
+
+
 class BokehMPLWrapper(ElementPlot):
     """
     Wraps an existing HoloViews matplotlib plot and converts
@@ -710,22 +828,8 @@ def update_frame(self, key, ranges=None, element=None):
             self.handles['plot'] = self._render_plot(element)
 
 
-class OverlayPlot(GenericOverlayPlot, ElementPlot):
+class OverlayPlot(GenericOverlayPlot, LegendPlot):
 
-    legend_position = param.ObjectSelector(objects=["top_right",
-                                                    "top_left",
-                                                    "bottom_left",
-                                                    "bottom_right",
-                                                    'right', 'left',
-                                                    'top', 'bottom'],
-                                                    default="top_right",
-                                                    doc="""
-        Allows selecting between a number of predefined legend position
-        options. The predefined options may be customized in the
-        legend_specs class attribute.""")
-
-    legend_cols = param.Integer(default=False, doc="""
-       Whether to lay out the legend as columns.""")
 
     tabs = param.Boolean(default=False, doc="""
         Whether to display overlaid plots in separate panes""")
@@ -734,11 +838,6 @@ class OverlayPlot(GenericOverlayPlot, ElementPlot):
 
     _update_handles = ['source']
 
-    legend_specs = {'right': dict(pos='right', loc=(5, -40)),
-                    'left': dict(pos='left', loc=(0, -40)),
-                    'top': dict(pos='above', loc=(120, 5)),
-                    'bottom': dict(pos='below', loc=(60, 0))}
-
     def _process_legend(self):
         plot = self.handles['plot']
         if not self.show_legend or len(plot.legend) == 0:

From 14048bdbf1967eea1ee71dad1c4072266ef660d3 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Wed, 14 Sep 2016 00:34:31 +0100
Subject: [PATCH 02/21] Added client side colormapping for PointPlot

---
 holoviews/plotting/bokeh/chart.py | 27 ++++++++++-----------------
 1 file changed, 10 insertions(+), 17 deletions(-)

diff --git a/holoviews/plotting/bokeh/chart.py b/holoviews/plotting/bokeh/chart.py
index 5a857f7940..8e3432b18f 100644
--- a/holoviews/plotting/bokeh/chart.py
+++ b/holoviews/plotting/bokeh/chart.py
@@ -12,12 +12,12 @@
 from ...core.util import max_range, basestring, dimension_sanitizer
 from ...core.options import abbreviated_exception
 from ..util import compute_sizes, get_sideplot_ranges, match_spec, map_colors
-from .element import ElementPlot, line_properties, fill_properties
+from .element import ElementPlot, ColorbarPlot, line_properties, fill_properties
 from .path import PathPlot, PolygonPlot
 from .util import get_cmap, mpl_to_bokeh, update_plot, rgb2hex, bokeh_version
 
 
-class PointPlot(ElementPlot):
+class PointPlot(ColorbarPlot):
 
     color_index = param.ClassSelector(default=3, class_=(basestring, int),
                                       allow_None=True, doc="""
@@ -55,21 +55,12 @@ def get_data(self, element, ranges=None, empty=False):
         mapping = dict(x=dims[xidx], y=dims[yidx])
         data = {}
 
-        cmap = style.get('palette', style.get('cmap', None))
         cdim = element.get_dimension(self.color_index)
-        if cdim and cmap:
-            map_key = 'color_' + cdim.name
-            mapping['color'] = map_key
-            if empty:
-                data[map_key] = []
-            else:
-                cmap = get_cmap(cmap)
-                colors = element.dimension_values(self.color_index)
-                if colors.dtype.kind in 'if':
-                    crange = ranges.get(cdim.name, element.range(cdim.name))
-                else:
-                    crange = np.unique(colors)
-                data[map_key] = map_colors(colors, crange, cmap)
+        if cdim:
+            mapper = self._get_colormapper(cdim, element, ranges, style)
+            data[cdim.name] = [] if empty else element.dimension_values(cdim)
+            mapping['color'] = {'field': cdim.name,
+                                'transform': mapper}
 
         sdim = element.get_dimension(self.size_index)
         if sdim:
@@ -98,7 +89,7 @@ def get_batched_data(self, element, ranges=None, empty=False):
             eldata, elmapping = self.get_data(el, ranges, empty)
             for k, eld in eldata.items():
                 data[k].append(eld)
-            if 'color' not in eldata:
+            if 'color' not in elmapping:
                 zorder = self.get_zorder(element, key, el)
                 val = style[zorder].get('color')
                 elmapping['color'] = 'color'
@@ -128,6 +119,8 @@ def _init_glyph(self, plot, mapping, properties):
         else:
             plot_method = self._plot_methods.get('batched' if self.batched else 'single')
             renderer = getattr(plot, plot_method)(**dict(properties, **mapping))
+        if self.colorbar and 'color_mapper' in self.handles:
+            self._draw_colorbar(plot, self.handles['color_mapper'])
         return renderer, renderer.glyph
 
 

From 3e383f8e2f6d47794100d36141e9b939943ab14c Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Wed, 14 Sep 2016 00:35:21 +0100
Subject: [PATCH 03/21] Added client side colormapping for SideHistogramPlot

---
 holoviews/plotting/bokeh/chart.py | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/holoviews/plotting/bokeh/chart.py b/holoviews/plotting/bokeh/chart.py
index 8e3432b18f..36472c817c 100644
--- a/holoviews/plotting/bokeh/chart.py
+++ b/holoviews/plotting/bokeh/chart.py
@@ -232,7 +232,7 @@ def get_data(self, element, ranges=None, empty=None):
         return (data, mapping)
 
 
-class SideHistogramPlot(HistogramPlot):
+class SideHistogramPlot(HistogramPlot, ColorbarPlot):
 
     style_opts = HistogramPlot.style_opts + ['cmap']
 
@@ -255,19 +255,20 @@ def get_data(self, element, ranges=None, empty=None):
             data = dict(top=element.values, left=element.edges[:-1],
                         right=element.edges[1:])
 
-        dim = element.get_dimension(0).name
+        dim = element.get_dimension(0)
         main = self.adjoined.main
-        range_item, main_range, dim = get_sideplot_ranges(self, element, main, ranges)
-        vals = element.dimension_values(dim)
+        range_item, main_range, _ = get_sideplot_ranges(self, element, main, ranges)
         if isinstance(range_item, (Raster, Points, Polygons, Spikes)):
             style = self.lookup_options(range_item, 'style')[self.cyclic_index]
         else:
             style = {}
 
         if 'cmap' in style or 'palette' in style:
-            cmap = get_cmap(style.get('cmap', style.get('palette', None)))
-            data['color'] = [] if empty else map_colors(vals, main_range, cmap)
-            mapping['fill_color'] = 'color'
+            main_range = {dim.name: main_range}
+            mapper = self._get_colormapper(dim, element, main_range, style)
+            data[dim.name] = [] if empty else element.dimension_values(dim)
+            mapping['fill_color'] = {'field': dim.name,
+                                     'transform': mapper}
         self._get_hover_data(data, element, empty)
         return (data, mapping)
 

From 883e185dc5da1c1cca21d374862a0d3afd5f7e27 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Wed, 14 Sep 2016 00:36:11 +0100
Subject: [PATCH 04/21] Added client side colormapping for PolygonPlot

---
 holoviews/plotting/bokeh/path.py | 22 ++++++++++++----------
 1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/holoviews/plotting/bokeh/path.py b/holoviews/plotting/bokeh/path.py
index eedc5566fa..e4cc8118cf 100644
--- a/holoviews/plotting/bokeh/path.py
+++ b/holoviews/plotting/bokeh/path.py
@@ -7,7 +7,7 @@
 
 from ...core import util
 from ..util import map_colors
-from .element import ElementPlot, line_properties, fill_properties
+from .element import ElementPlot, ColorbarPlot, line_properties, fill_properties
 from .util import get_cmap, rgb2hex
 
 
@@ -44,7 +44,7 @@ def get_batched_data(self, element, ranges=None, empty=False):
         return data, elmapping
 
 
-class PolygonPlot(PathPlot):
+class PolygonPlot(ColorbarPlot, PathPlot):
 
     style_opts = ['color', 'cmap', 'palette'] + line_properties + fill_properties
     _plot_methods = dict(single='patches', batched='patches')
@@ -74,15 +74,17 @@ def get_data(self, element, ranges=None, empty=False):
         data = dict(xs=ys, ys=xs) if self.invert_axes else dict(xs=xs, ys=ys)
 
         style = self.style[self.cyclic_index]
-        cmap = style.get('palette', style.get('cmap', None))
         mapping = dict(self._mapping)
-        if cmap and element.level is not None:
-            cmap = get_cmap(cmap)
-            colors = map_colors(np.array([element.level]), ranges[element.vdims[0].name], cmap)
-            mapping['color'] = 'color'
-            data['color'] = [] if empty else list(colors)*len(element.data)
-            dim_name = util.dimension_sanitizer(element.vdims[0].name)
+
+        if element.vdims and element.level is not None:
+            cdim = element.vdims[0]
+            mapper = self._get_colormapper(cdim, element, ranges, style)
+            data[cdim.name] = [] if empty else element.dimension_values(2)
+            mapping['fill_color'] = {'field': cdim.name,
+                                     'transform': mapper}
+
         if 'hover' in self.tools+self.default_tools:
+            dim_name = util.dimension_sanitizer(element.vdims[0].name)
             for k, v in self.overlay_dims.items():
                 dim = util.dimension_sanitizer(k.name)
                 data[dim] = [v for _ in range(len(xs))]
@@ -99,7 +101,7 @@ def get_batched_data(self, element, ranges=None, empty=False):
             eldata, elmapping = self.get_data(el, ranges, empty)
             for k, eld in eldata.items():
                 data[k].extend(eld)
-            if 'color' not in eldata:
+            if 'color' not in elmapping:
                 zorder = self.get_zorder(element, key, el)
                 val = style[zorder].get('color')
                 elmapping['color'] = 'color'

From ac35b2f4330a9ce5e1d5abdbd621e4010f0b069a Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Wed, 14 Sep 2016 00:37:06 +0100
Subject: [PATCH 05/21] Added colorbars for RasterPlot

---
 holoviews/plotting/bokeh/raster.py | 27 ++++++---------------------
 1 file changed, 6 insertions(+), 21 deletions(-)

diff --git a/holoviews/plotting/bokeh/raster.py b/holoviews/plotting/bokeh/raster.py
index 3d1819093a..0ddde4f4d2 100644
--- a/holoviews/plotting/bokeh/raster.py
+++ b/holoviews/plotting/bokeh/raster.py
@@ -1,24 +1,15 @@
 import numpy as np
 import param
 
-from bokeh.models.mappers import LinearColorMapper
-try:
-    from bokeh.models.mappers import LogColorMapper
-except ImportError:
-    LogColorMapper = None
-
 from ...core.util import cartesian_product
 from ...element import Image, Raster, RGB
 from ..renderer import SkipRendering
 from ..util import map_colors
-from .element import ElementPlot, line_properties, fill_properties
-from .util import mplcmap_to_palette, get_cmap, hsv_to_rgb
-
+from .element import ElementPlot, ColorbarPlot, line_properties, fill_properties
+from .util import mplcmap_to_palette, get_cmap, hsv_to_rgb, mpl_to_bokeh
 
-class RasterPlot(ElementPlot):
 
-    logz  = param.Boolean(default=False, doc="""
-         Whether to apply log scaling to the z-axis.""")
+class RasterPlot(ColorbarPlot):
 
     show_legend = param.Boolean(default=False, doc="""
         Whether to show legend for the plot.""")
@@ -56,15 +47,9 @@ def _glyph_properties(self, plot, element, source, ranges):
         properties = super(RasterPlot, self)._glyph_properties(plot, element,
                                                                source, ranges)
         properties = {k: v for k, v in properties.items()}
-        val_dim = [d.name for d in element.vdims][0]
-        low, high = ranges.get(val_dim)
-        if 'cmap' in properties:
-            palette = mplcmap_to_palette(properties.pop('cmap', None))
-        colormapper = LogColorMapper if self.logz else LinearColorMapper
-        cmap = colormapper(palette, low=low, high=high)
-        properties['color_mapper'] = cmap
-        if 'color_mapper' not in self.handles:
-            self.handles['color_mapper'] = cmap
+        val_dim = [d for d in element.vdims][0]
+        properties['color_mapper'] = self._get_colormapper(val_dim, element, ranges,
+                                                           properties)
         return properties
 
 

From da511ff9fa57ac640ce1861cd8324d9c49bbbfed Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Wed, 14 Sep 2016 00:37:33 +0100
Subject: [PATCH 06/21] Added client-side colormapping for QuadMeshPlot

---
 holoviews/plotting/bokeh/raster.py | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/holoviews/plotting/bokeh/raster.py b/holoviews/plotting/bokeh/raster.py
index 0ddde4f4d2..8111a5ba4c 100644
--- a/holoviews/plotting/bokeh/raster.py
+++ b/holoviews/plotting/bokeh/raster.py
@@ -151,7 +151,7 @@ def get_data(self, element, ranges=None, empty=False):
         return (data, {'x': x, 'y': y, 'fill_color': 'color', 'height': 1, 'width': 1})
 
 
-class QuadMeshPlot(ElementPlot):
+class QuadMeshPlot(ColorbarPlot):
 
     show_legend = param.Boolean(default=False, doc="""
         Whether to show legend for the plot.""")
@@ -161,24 +161,23 @@ class QuadMeshPlot(ElementPlot):
 
     def get_data(self, element, ranges=None, empty=False):
         x, y, z = element.dimensions(label=True)
+        style = self.style[self.cyclic_index]
+        cmapper = self._get_colormapper(element.vdims[0], element, ranges, style)
         if empty:
-            data = {x: [], y: [], z: [], 'color': [], 'height': [], 'width': []}
+            data = {x: [], y: [], z: [], 'height': [], 'width': []}
         else:
-            style = self.style[self.cyclic_index]
-            cmap = style.get('palette', style.get('cmap', None))
-            cmap = get_cmap(cmap)
             if len(set(v.shape for v in element.data)) == 1:
                 raise SkipRendering("Bokeh QuadMeshPlot only supports rectangular meshes")
             zvals = element.data[2].T.flatten()
-            colors = map_colors(zvals, ranges[z], cmap)
             xvals = element.dimension_values(0, False)
             yvals = element.dimension_values(1, False)
             widths = np.diff(element.data[0])
             heights = np.diff(element.data[1])
             xs, ys = cartesian_product([xvals, yvals])
             ws, hs = cartesian_product([widths, heights])
-            data = {x: xs.flat, y: ys.flat, z: zvals, 'color': colors,
+            data = {x: xs.flat, y: ys.flat, z: zvals,
                     'widths': ws.flat, 'heights': hs.flat}
 
-        return (data, {'x': x, 'y': y, 'fill_color': 'color',
+        return (data, {'x': x, 'y': y,
+                       'fill_color': {'field': z, 'transform': cmapper},
                        'height': 'heights', 'width': 'widths'})

From 59b94736bcbc085b7839fa7ffd96e22aeae999b4 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Wed, 14 Sep 2016 00:38:24 +0100
Subject: [PATCH 07/21] Added client side colormapping for SpikesPlot

---
 holoviews/plotting/bokeh/chart.py | 22 +++++++---------------
 1 file changed, 7 insertions(+), 15 deletions(-)

diff --git a/holoviews/plotting/bokeh/chart.py b/holoviews/plotting/bokeh/chart.py
index 36472c817c..a7d48ee571 100644
--- a/holoviews/plotting/bokeh/chart.py
+++ b/holoviews/plotting/bokeh/chart.py
@@ -308,7 +308,7 @@ def get_data(self, element, ranges=None, empty=False):
         return (data, dict(self._mapping))
 
 
-class SpikesPlot(PathPlot):
+class SpikesPlot(PathPlot, ColorbarPlot):
 
     color_index = param.ClassSelector(default=1, class_=(basestring, int), doc="""
       Index of the dimension from which the color will the drawn""")
@@ -346,22 +346,14 @@ def get_data(self, element, ranges=None, empty=False):
             xs, ys = zip(*(((x[0], x[0]), (pos+height, pos))
                            for x in element.array(dims[:1])))
 
-        if not empty and self.invert_axes: keys = keys[::-1]
+        if not empty and self.invert_axes: xs, ys = ys, xs
         data = dict(zip(('xs', 'ys'), (xs, ys)))
-
-        cmap = style.get('palette', style.get('cmap', None))
         cdim = element.get_dimension(self.color_index)
-        if cdim and cmap:
-            map_key = 'color_' + cdim.name
-            mapping['color'] = map_key
-            if empty:
-                colors = []
-            else:
-                cmap = get_cmap(cmap)
-                cvals = element.dimension_values(cdim)
-                crange = ranges.get(cdim.name, None)
-                colors = map_colors(cvals, crange, cmap)
-            data[map_key] = colors
+        if cdim:
+            mapper = self._get_colormapper(cdim, element, ranges, style)
+            data[cdim.name] = [] if empty else element.dimension_values(cdim)
+            mapping['color'] = {'field': cdim.name,
+                                'transform': mapper}
 
         if 'hover' in self.tools+self.default_tools and not empty:
             for d in dims:

From 84a0dc44458078c42a9b79224c9e0fe6cb3928be Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Wed, 14 Sep 2016 00:38:51 +0100
Subject: [PATCH 08/21] Moved toolbar on top to avoid clashes with colorbar

---
 holoviews/plotting/bokeh/element.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/holoviews/plotting/bokeh/element.py b/holoviews/plotting/bokeh/element.py
index 4e65648ca9..6239e68a72 100644
--- a/holoviews/plotting/bokeh/element.py
+++ b/holoviews/plotting/bokeh/element.py
@@ -289,6 +289,7 @@ def _init_plot(self, key, element, plots, ranges=None):
 
         properties['webgl'] = Store.renderers[self.renderer.backend].webgl
         return bokeh.plotting.Figure(x_axis_type=x_axis_type,
+                                     toolbar_location='above',
                                      y_axis_type=y_axis_type, title=title,
                                      tools=tools, **properties)
 

From dee556fb4f8a0d732bf05e97267f6cc43db6dea6 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Wed, 14 Sep 2016 17:37:27 +0100
Subject: [PATCH 09/21] Added client side colormapping for HeatmapPlot

---
 holoviews/plotting/bokeh/raster.py | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/holoviews/plotting/bokeh/raster.py b/holoviews/plotting/bokeh/raster.py
index 8111a5ba4c..961c244460 100644
--- a/holoviews/plotting/bokeh/raster.py
+++ b/holoviews/plotting/bokeh/raster.py
@@ -116,7 +116,7 @@ def get_data(self, element, ranges=None, empty=False):
         return super(HSVPlot, self).get_data(rgb, ranges, empty)
 
 
-class HeatmapPlot(ElementPlot):
+class HeatmapPlot(ColorbarPlot):
 
     show_legend = param.Boolean(default=False, doc="""
         Whether to show legend for the plot.""")
@@ -129,6 +129,7 @@ def _axes_props(self, plots, subplots, element, ranges):
         labels = self._get_axis_labels(dims)
         xvals, yvals = [element.dimension_values(i, False)
                         for i in range(2)]
+        if self.invert_yaxis: yvals = yvals[::-1]
         plot_ranges = {'x_range': [str(x) for x in xvals],
                        'y_range': [str(y) for y in yvals]}
         return ('auto', 'auto'), labels, plot_ranges
@@ -136,19 +137,18 @@ def _axes_props(self, plots, subplots, element, ranges):
 
     def get_data(self, element, ranges=None, empty=False):
         x, y, z = element.dimensions(label=True)
+        style = self.style[self.cyclic_index]
+        cmapper = self._get_colormapper(element.vdims[0], element, ranges, style)
         if empty:
             data = {x: [], y: [], z: [], 'color': []}
         else:
-            style = self.style[self.cyclic_index]
-            cmap = style.get('palette', style.get('cmap', None))
-            cmap = get_cmap(cmap)
             zvals = np.rot90(element.raster, 3).flatten()
-            colors = map_colors(zvals, ranges[z], cmap)
             xvals, yvals = [[str(v) for v in element.dimension_values(i)]
                             for i in range(2)]
-            data = {x: xvals, y: yvals, z: zvals, 'color': colors}
+            data = {x: xvals, y: yvals, z: zvals}
 
-        return (data, {'x': x, 'y': y, 'fill_color': 'color', 'height': 1, 'width': 1})
+        return (data, {'x': x, 'y': y, 'fill_color': {'field': z, 'transform': cmapper},
+                       'height': 1, 'width': 1})
 
 
 class QuadMeshPlot(ColorbarPlot):

From f2884e1f103c609370954d437ac6c3f90c36d6e7 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Wed, 14 Sep 2016 18:02:34 +0100
Subject: [PATCH 10/21] Handled updating of colormapping ranges

---
 holoviews/plotting/bokeh/element.py | 13 +++++++++++++
 holoviews/plotting/bokeh/raster.py  | 10 ----------
 2 files changed, 13 insertions(+), 10 deletions(-)

diff --git a/holoviews/plotting/bokeh/element.py b/holoviews/plotting/bokeh/element.py
index 6239e68a72..cf8cd116ff 100644
--- a/holoviews/plotting/bokeh/element.py
+++ b/holoviews/plotting/bokeh/element.py
@@ -710,6 +710,19 @@ def _init_glyph(self, plot, mapping, properties):
         return ret
 
 
+    def _update_glyph(self, glyph, properties, mapping):
+        allowed_properties = glyph.properties()
+        cmappers = [v.get('transform') for v in mapping.values()
+                    if isinstance(v, dict)]
+        cmappers.append(properties.pop('color_mapper', None))
+        for cm in cmappers:
+            if cm:
+                self.handles['color_mapper'].low = cm.low
+                self.handles['color_mapper'].high = cm.high
+        merged = dict(properties, **mapping)
+        glyph.set(**{k: v for k, v in merged.items()
+                     if k in allowed_properties})
+
 
 class LegendPlot(ElementPlot):
 
diff --git a/holoviews/plotting/bokeh/raster.py b/holoviews/plotting/bokeh/raster.py
index 961c244460..f70e952378 100644
--- a/holoviews/plotting/bokeh/raster.py
+++ b/holoviews/plotting/bokeh/raster.py
@@ -53,16 +53,6 @@ def _glyph_properties(self, plot, element, source, ranges):
         return properties
 
 
-    def _update_glyph(self, glyph, properties, mapping):
-        allowed_properties = glyph.properties()
-        cmap = properties.pop('color_mapper', None)
-        if cmap:
-            glyph.color_mapper.low = cmap.low
-            glyph.color_mapper.high = cmap.high
-        merged = dict(properties, **mapping)
-        glyph.set(**{k: v for k, v in merged.items()
-                     if k in allowed_properties})
-
 
 class ImagePlot(RasterPlot):
 

From 8f00b04cdce69c37660dbca25c680a4993c14670 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Wed, 14 Sep 2016 18:09:42 +0100
Subject: [PATCH 11/21] Added colorbar border by default

---
 holoviews/plotting/bokeh/element.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/holoviews/plotting/bokeh/element.py b/holoviews/plotting/bokeh/element.py
index cf8cd116ff..e1d2c4ba0c 100644
--- a/holoviews/plotting/bokeh/element.py
+++ b/holoviews/plotting/bokeh/element.py
@@ -675,7 +675,9 @@ def _draw_colorbar(self, plot, color_mapper):
             ticker = LogTicker()
         else:
             ticker = BasicTicker()
-        cbar_opts = self.colorbar_specs[self.colorbar_position]
+        cbar_opts = dict(self.colorbar_specs[self.colorbar_position],
+                         bar_line_color='black', label_standoff=8,
+                         major_tick_line_color='black')
 
         # Check if there is a colorbar in the same position
         pos = cbar_opts['pos']

From af0b2dd0af6174d6b47ed6ab2e70e7c2587534e1 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Wed, 14 Sep 2016 18:52:32 +0100
Subject: [PATCH 12/21] Made toolbar position customizable

Allows avoiding overlap with legends, colorbars and titles
---
 holoviews/plotting/bokeh/element.py | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/holoviews/plotting/bokeh/element.py b/holoviews/plotting/bokeh/element.py
index e1d2c4ba0c..e924b1dadf 100644
--- a/holoviews/plotting/bokeh/element.py
+++ b/holoviews/plotting/bokeh/element.py
@@ -113,6 +113,13 @@ class ElementPlot(BokehPlot, GenericElementPlot):
     tools = param.List(default=[], doc="""
         A list of plugin tools to use on the plot.""")
 
+    toolbar = param.ObjectSelector(default='right',
+                                   objects=["above", "below",
+                                            "left", "right", None],
+                                   doc="""
+        The toolbar location, must be one of 'above', 'below',
+        'left', 'right', None.""")
+
     xaxis = param.ObjectSelector(default='bottom',
                                  objects=['top', 'bottom', 'bare', 'top-bare',
                                           'bottom-bare', None], doc="""
@@ -277,7 +284,6 @@ def _init_plot(self, key, element, plots, ranges=None):
         axis_types, labels, plot_ranges = self._axes_props(plots, subplots, element, ranges)
         xlabel, ylabel, _ = labels
         x_axis_type, y_axis_type = axis_types
-        tools = self._init_tools(element)
         properties = dict(plot_ranges)
         properties['x_axis_label'] = xlabel if 'x' in self.show_labels else ' '
         properties['y_axis_label'] = ylabel if 'y' in self.show_labels else ' '
@@ -287,11 +293,15 @@ def _init_plot(self, key, element, plots, ranges=None):
         else:
             title = ''
 
+        if self.toolbar:
+            tools = self._init_tools(element)
+            properties['tools'] = tools
+            properties['toolbar_location'] = self.toolbar
+
         properties['webgl'] = Store.renderers[self.renderer.backend].webgl
         return bokeh.plotting.Figure(x_axis_type=x_axis_type,
-                                     toolbar_location='above',
                                      y_axis_type=y_axis_type, title=title,
-                                     tools=tools, **properties)
+                                     **properties)
 
 
     def _plot_properties(self, key, plot, element):

From 122a3bab22d7161ffb84c9fd6ac95e208f621533 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Wed, 14 Sep 2016 19:04:56 +0100
Subject: [PATCH 13/21] Cleaned up ColorbarPlot and added docstring

---
 holoviews/plotting/bokeh/element.py | 53 ++++++++++++++++-------------
 1 file changed, 30 insertions(+), 23 deletions(-)

diff --git a/holoviews/plotting/bokeh/element.py b/holoviews/plotting/bokeh/element.py
index e924b1dadf..53451291be 100644
--- a/holoviews/plotting/bokeh/element.py
+++ b/holoviews/plotting/bokeh/element.py
@@ -640,18 +640,40 @@ def framewise(self):
 
 
 class ColorbarPlot(ElementPlot):
+    """
+    ColorbarPlot provides methods to create colormappers and colorbar
+    models which can be added to a glyph. Additionally it provides
+    parameters to control the position and other styling options of
+    the colorbar. The default colorbar_position options are defined
+    by the colorbar_specs, but may be overridden by the colorbar_opts.
+    """
+
+    colorbar_specs = {'right':     {'pos': 'right',
+                                    'opts': {'location': (0, 0)}},
+                      'left':      {'pos': 'left',
+                                    'opts':{'location':(0, 0)}},
+                      'bottom':    {'pos': 'below',
+                                    'opts': {'location': (0, 0),
+                                             'orientation':'horizontal'}},
+                      'top':       {'pos': 'above',
+                                    'opts': {'location':(0, 0),
+                                             'orientation':'horizontal'}},
+                      'top_right':   {'pos': 'center',
+                                      'opts': {'location': 'top_right'}},
+                      'top_left':    {'pos': 'center',
+                                      'opts': {'location': 'top_left'}},
+                      'bottom_left': {'pos': 'center',
+                                      'opts': {'location': 'bottom_left',
+                                               'orientation': 'horizontal'}},
+                      'bottom_right': {'pos': 'center',
+                                      'opts': {'location': 'bottom_right',
+                                               'orientation': 'horizontal'}}}
 
     colorbar = param.Boolean(default=False, doc="""
         Whether to display a colorbar.""")
 
-    colorbar_position = param.ObjectSelector(objects=["top_right",
-                                                      "top_left",
-                                                      "bottom_left",
-                                                      "bottom_right",
-                                                      'right', 'left',
-                                                      'top', 'bottom'],
-                                             default="right",
-                                             doc="""
+    colorbar_position = param.ObjectSelector(objects=list(colorbar_specs),
+                                             default="right", doc="""
         Allows selecting between a number of predefined colorbar position
         options. The predefined options may be customized in the
         colorbar_specs class attribute.""")
@@ -662,21 +684,6 @@ class ColorbarPlot(ElementPlot):
         location, orientation, height, width, scale_alpha, title, title_props,
         margin, padding, background_fill_color and more.""")
 
-    colorbar_specs = {'right': {'pos': 'right', 'opts': {'location': (0, 0)}},
-                      'left': {'pos': 'left', 'opts':{'location':(0, 0)}},
-                      'top_right': {'pos': 'center', 'opts': {'location': 'top_right'}},
-                      'top_left': {'pos': 'center', 'opts': {'location': 'top_left'}},
-                      'top': {'opts': {'location':(0, 0), 'orientation':'horizontal'},
-                              'pos': 'above'},
-                      'bottom': {'opts': {'location': (0, 0), 'orientation':'horizontal'},
-                                 'pos': 'below'},
-                      'bottom_left': {'pos': 'center',
-                                      'opts': {'location': 'bottom_center',
-                                               'orientation': 'horizontal'}},
-                      'bottom_right': {'pos': 'center',
-                                      'opts': {'location': 'bottom_right',
-                                               'orientation': 'horizontal'}}}
-
     logz  = param.Boolean(default=False, doc="""
          Whether to apply log scaling to the z-axis.""")
 

From b219c23b4f456b9d05d756f69801c4f1a7e6795e Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Wed, 14 Sep 2016 22:04:36 +0100
Subject: [PATCH 14/21] Defined default colormap

---
 holoviews/plotting/bokeh/element.py | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/holoviews/plotting/bokeh/element.py b/holoviews/plotting/bokeh/element.py
index 53451291be..9f8f9b69ee 100644
--- a/holoviews/plotting/bokeh/element.py
+++ b/holoviews/plotting/bokeh/element.py
@@ -710,8 +710,7 @@ def _draw_colorbar(self, plot, color_mapper):
 
     def _get_colormapper(self, dim, element, ranges, style):
         low, high = ranges.get(dim.name)
-        if 'cmap' in style:
-            palette = mplcmap_to_palette(style.pop('cmap', None))
+        palette = mplcmap_to_palette(style.pop('cmap', 'viridis'))
         colormapper = LogColorMapper if self.logz else LinearColorMapper
         cmapper = colormapper(palette, low=low, high=high)
         if 'color_mapper' not in self.handles:

From 8a83577b48f9ad442d03e69e29ae6bc2aaa1b357 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Wed, 14 Sep 2016 22:05:55 +0100
Subject: [PATCH 15/21] Added colormapping unit tests

---
 tests/testplotinstantiation.py | 49 ++++++++++++++++++++++++++++++++--
 1 file changed, 47 insertions(+), 2 deletions(-)

diff --git a/tests/testplotinstantiation.py b/tests/testplotinstantiation.py
index 339a45eb37..f8c6399cb9 100644
--- a/tests/testplotinstantiation.py
+++ b/tests/testplotinstantiation.py
@@ -6,8 +6,9 @@
 from io import BytesIO
 
 import numpy as np
-from holoviews import (Dimension, Curve, Scatter, Overlay, DynamicMap,
-                       Store, Image, VLine, NdOverlay, Points)
+from holoviews import (Dimension, Overlay, DynamicMap, Store, NdOverlay)
+from holoviews.element import (Curve, Scatter, Image, VLine, Points,
+                               HeatMap, QuadMesh, Spikes)
 from holoviews.element.comparison import ComparisonTestCase
 from holoviews.streams import PositionXY
 
@@ -24,6 +25,7 @@
 try:
     import holoviews.plotting.bokeh
     bokeh_renderer = Store.renderers['bokeh']
+    from bokeh.models.mappers import LinearColorMapper, LogColorMapper
 except:
     bokeh_renderer = None
 
@@ -31,6 +33,8 @@
 class TestMPLPlotInstantiation(ComparisonTestCase):
 
     def setUp(self):
+        self.previous_backend = Store.current_backend
+        Store.current_backend = 'matplotlib'
         if mpl_renderer is None:
             raise SkipTest("Matplotlib required to test plot instantiation")
         self.default_comm, _ = mpl_renderer.comms['default']
@@ -38,6 +42,7 @@ def setUp(self):
 
     def teardown(self):
         mpl_renderer.comms['default'] = (self.default_comm, '')
+        Store.current_backend = self.previous_backend
 
     def test_interleaved_overlay(self):
         """
@@ -72,11 +77,51 @@ def test_dynamic_streams_refresh(self):
 class TestBokehPlotInstantiation(ComparisonTestCase):
 
     def setUp(self):
+        self.previous_backend = Store.current_backend
+        Store.current_backend = 'bokeh'
+
         if not bokeh_renderer:
             raise SkipTest("Bokeh required to test plot instantiation")
 
+    def teardown(self):
+        Store.current_backend = self.previous_backend
+
     def test_batched_plot(self):
         overlay = NdOverlay({i: Points(np.arange(i)) for i in range(1, 100)})
         plot = bokeh_renderer.get_plot(overlay)
         extents = plot.get_extents(overlay, {})
         self.assertEqual(extents, (0, 0, 98, 98))
+
+    def _test_colormapping(self, element, dim, log=False):
+        plot = bokeh_renderer.get_plot(element)
+        plot.initialize_plot()
+        fig = plot.state
+        cmapper = plot.handles['color_mapper']
+        low, high = element.range(dim)
+        self.assertEqual(cmapper.low, low)
+        self.assertEqual(cmapper.high, high)
+        mapper_type = LogColorMapper if log else LinearColorMapper
+        self.assertTrue(isinstance(cmapper, mapper_type))
+
+    def test_points_colormapping(self):
+        points = Points(np.random.rand(10, 4), vdims=['a', 'b'])
+        self._test_colormapping(points, 3)
+
+    def test_image_colormapping(self):
+        img = Image(np.random.rand(10, 10))(plot=dict(logz=True))
+        self._test_colormapping(img, 2, True)
+
+    def test_heatmap_colormapping(self):
+        hm = HeatMap([(1,1,1), (2,2,0)])
+        self._test_colormapping(hm, 2)
+
+    def test_quadmesh_colormapping(self):
+        n = 21
+        xs = np.logspace(1, 3, n)
+        ys = np.linspace(1, 10, n)
+        qmesh = QuadMesh((xs, ys, np.random.rand(n-1, n-1)))
+        self._test_colormapping(qmesh, 2)
+
+    def test_spikes_colormapping(self):
+        spikes = Spikes(np.random.rand(20, 2), vdims=['Intensity'])
+        self._test_colormapping(spikes, 1)

From 65c0d21cfa948add89e0df5689ace8211998211a Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Wed, 14 Sep 2016 22:20:46 +0100
Subject: [PATCH 16/21] Added colormapper to update handles of ColorbarPlot

---
 holoviews/plotting/bokeh/element.py | 2 ++
 holoviews/plotting/bokeh/raster.py  | 1 -
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/holoviews/plotting/bokeh/element.py b/holoviews/plotting/bokeh/element.py
index 9f8f9b69ee..fa317814be 100644
--- a/holoviews/plotting/bokeh/element.py
+++ b/holoviews/plotting/bokeh/element.py
@@ -687,6 +687,8 @@ class ColorbarPlot(ElementPlot):
     logz  = param.Boolean(default=False, doc="""
          Whether to apply log scaling to the z-axis.""")
 
+    _update_handles = ['color_mapper', 'source', 'glyph']
+
     def _draw_colorbar(self, plot, color_mapper):
         if LogColorMapper and isinstance(color_mapper, LogColorMapper):
             ticker = LogTicker()
diff --git a/holoviews/plotting/bokeh/raster.py b/holoviews/plotting/bokeh/raster.py
index f70e952378..270cde329b 100644
--- a/holoviews/plotting/bokeh/raster.py
+++ b/holoviews/plotting/bokeh/raster.py
@@ -16,7 +16,6 @@ class RasterPlot(ColorbarPlot):
 
     style_opts = ['cmap']
     _plot_methods = dict(single='image')
-    _update_handles = ['color_mapper', 'source', 'glyph']
 
     def __init__(self, *args, **kwargs):
         super(RasterPlot, self).__init__(*args, **kwargs)

From c211f2a8c222c726584931bc0bc971538a5b4271 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Wed, 14 Sep 2016 22:42:31 +0100
Subject: [PATCH 17/21] Fixed setting of colorbar border

---
 holoviews/plotting/bokeh/element.py | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/holoviews/plotting/bokeh/element.py b/holoviews/plotting/bokeh/element.py
index fa317814be..6fa80b516f 100644
--- a/holoviews/plotting/bokeh/element.py
+++ b/holoviews/plotting/bokeh/element.py
@@ -694,17 +694,17 @@ def _draw_colorbar(self, plot, color_mapper):
             ticker = LogTicker()
         else:
             ticker = BasicTicker()
-        cbar_opts = dict(self.colorbar_specs[self.colorbar_position],
-                         bar_line_color='black', label_standoff=8,
-                         major_tick_line_color='black')
+        cbar_opts = dict(self.colorbar_specs[self.colorbar_position])
 
         # Check if there is a colorbar in the same position
         pos = cbar_opts['pos']
         if any(isinstance(model, ColorBar) for model in getattr(plot, pos, [])):
             return
 
+        opts = dict(cbar_opts['opts'], bar_line_color='black',
+                    label_standoff=8, major_tick_line_color='black')
         color_bar = ColorBar(color_mapper=color_mapper, ticker=ticker,
-                             **dict(cbar_opts['opts'], **self.colorbar_opts))
+                             **dict(opts, **self.colorbar_opts))
 
         plot.add_layout(color_bar, pos)
         self.handles['colorbar'] = color_bar

From f520bff3ca36df40b112391555cc832306883894 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Wed, 14 Sep 2016 23:31:05 +0100
Subject: [PATCH 18/21] Allowed updating the colormapper palette

---
 holoviews/plotting/bokeh/element.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/holoviews/plotting/bokeh/element.py b/holoviews/plotting/bokeh/element.py
index 6fa80b516f..523fb9bfef 100644
--- a/holoviews/plotting/bokeh/element.py
+++ b/holoviews/plotting/bokeh/element.py
@@ -739,6 +739,7 @@ def _update_glyph(self, glyph, properties, mapping):
             if cm:
                 self.handles['color_mapper'].low = cm.low
                 self.handles['color_mapper'].high = cm.high
+                self.handles['color_mapper'].palette = cm.palette
         merged = dict(properties, **mapping)
         glyph.set(**{k: v for k, v in merged.items()
                      if k in allowed_properties})

From c35d6b26c12b334828b77e083285da177264fcf4 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Wed, 14 Sep 2016 23:34:13 +0100
Subject: [PATCH 19/21] Made colorbar defaults a class attribute

---
 holoviews/plotting/bokeh/element.py | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/holoviews/plotting/bokeh/element.py b/holoviews/plotting/bokeh/element.py
index 523fb9bfef..d567b93e52 100644
--- a/holoviews/plotting/bokeh/element.py
+++ b/holoviews/plotting/bokeh/element.py
@@ -689,6 +689,9 @@ class ColorbarPlot(ElementPlot):
 
     _update_handles = ['color_mapper', 'source', 'glyph']
 
+    _colorbar_defaults = dict(bar_line_color='black', label_standoff=8,
+                              major_tick_line_color='black')
+
     def _draw_colorbar(self, plot, color_mapper):
         if LogColorMapper and isinstance(color_mapper, LogColorMapper):
             ticker = LogTicker()
@@ -701,8 +704,7 @@ def _draw_colorbar(self, plot, color_mapper):
         if any(isinstance(model, ColorBar) for model in getattr(plot, pos, [])):
             return
 
-        opts = dict(cbar_opts['opts'], bar_line_color='black',
-                    label_standoff=8, major_tick_line_color='black')
+        opts = dict(cbar_opts['opts'], self._colorbar_defaults)
         color_bar = ColorBar(color_mapper=color_mapper, ticker=ticker,
                              **dict(opts, **self.colorbar_opts))
 

From 80899e61a533c0f91f9a4e612354c2c2bc5d7c06 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Wed, 14 Sep 2016 23:35:55 +0100
Subject: [PATCH 20/21] Renamed mapper to cmapper

---
 holoviews/plotting/bokeh/chart.py | 8 ++++----
 holoviews/plotting/bokeh/path.py  | 4 ++--
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/holoviews/plotting/bokeh/chart.py b/holoviews/plotting/bokeh/chart.py
index a7d48ee571..5446e3d8c3 100644
--- a/holoviews/plotting/bokeh/chart.py
+++ b/holoviews/plotting/bokeh/chart.py
@@ -265,10 +265,10 @@ def get_data(self, element, ranges=None, empty=None):
 
         if 'cmap' in style or 'palette' in style:
             main_range = {dim.name: main_range}
-            mapper = self._get_colormapper(dim, element, main_range, style)
+            cmapper = self._get_colormapper(dim, element, main_range, style)
             data[dim.name] = [] if empty else element.dimension_values(dim)
             mapping['fill_color'] = {'field': dim.name,
-                                     'transform': mapper}
+                                     'transform': cmapper}
         self._get_hover_data(data, element, empty)
         return (data, mapping)
 
@@ -350,10 +350,10 @@ def get_data(self, element, ranges=None, empty=False):
         data = dict(zip(('xs', 'ys'), (xs, ys)))
         cdim = element.get_dimension(self.color_index)
         if cdim:
-            mapper = self._get_colormapper(cdim, element, ranges, style)
+            cmapper = self._get_colormapper(cdim, element, ranges, style)
             data[cdim.name] = [] if empty else element.dimension_values(cdim)
             mapping['color'] = {'field': cdim.name,
-                                'transform': mapper}
+                                'transform': cmapper}
 
         if 'hover' in self.tools+self.default_tools and not empty:
             for d in dims:
diff --git a/holoviews/plotting/bokeh/path.py b/holoviews/plotting/bokeh/path.py
index e4cc8118cf..09930009ce 100644
--- a/holoviews/plotting/bokeh/path.py
+++ b/holoviews/plotting/bokeh/path.py
@@ -78,10 +78,10 @@ def get_data(self, element, ranges=None, empty=False):
 
         if element.vdims and element.level is not None:
             cdim = element.vdims[0]
-            mapper = self._get_colormapper(cdim, element, ranges, style)
+            cmapper = self._get_colormapper(cdim, element, ranges, style)
             data[cdim.name] = [] if empty else element.dimension_values(2)
             mapping['fill_color'] = {'field': cdim.name,
-                                     'transform': mapper}
+                                     'transform': cmapper}
 
         if 'hover' in self.tools+self.default_tools:
             dim_name = util.dimension_sanitizer(element.vdims[0].name)

From 9e2f1b631ba95d64b75303b4a4abd30c253d9ec2 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Wed, 14 Sep 2016 23:37:58 +0100
Subject: [PATCH 21/21] Added comment about colormapper instances

---
 holoviews/plotting/bokeh/element.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/holoviews/plotting/bokeh/element.py b/holoviews/plotting/bokeh/element.py
index d567b93e52..d2eb5bc1d9 100644
--- a/holoviews/plotting/bokeh/element.py
+++ b/holoviews/plotting/bokeh/element.py
@@ -717,6 +717,9 @@ def _get_colormapper(self, dim, element, ranges, style):
         palette = mplcmap_to_palette(style.pop('cmap', 'viridis'))
         colormapper = LogColorMapper if self.logz else LinearColorMapper
         cmapper = colormapper(palette, low=low, high=high)
+
+        # The initial colormapper instance is cached the first time
+        # and then updated with the values from new instances
         if 'color_mapper' not in self.handles:
             self.handles['color_mapper'] = cmapper
         return cmapper