fsleyes_widgets.utils.colourbarbitmap
¶
This module provides a single function, colourBarBitmap()
, which uses
matplotlib
to plot a colour bar. The colour bar is rendered off-screen
and returned as an RGBA bitmap.
-
fsleyes_widgets.utils.colourbarbitmap.
colourBarBitmap
(cmap, width, height, cmapResolution=256, negCmap=None, invert=False, gamma=1, ticks=None, ticklabels=None, tickalign=None, label=None, orientation='vertical', labelside='top', alpha=1.0, fontsize=10, bgColour=None, textColour='#ffffff', scale=1.0)¶ Plots a colour bar using
matplotlib
.The rendered colour bar is returned as a RGBA bitmap within a
numpy.uint8
array of size \(w \times h \times 4\), with the top-left pixel located at index[0, 0, :]
.A rendered colour bar will look something like this:
Parameters: - cmap – Name of a registered
matplotlib
colour map. - width – Colour bar width in pixels.
- height – Colour bar height in pixels.
- cmapResolution – Colour map resolution (number of distinct colours).
- negCmap – If provided, two colour maps are drawn, centered at 0.
- invert – If
True
, the colour map is inverted. - gamma – Gamma correction factor - exponentially weights the colour map scale towards one end.
- ticks – Locations of tick labels. Ignored if
ticklabels is None
. - ticklabels – Tick labels.
- tickalign – Tick alignment (one for each tick, either
'left'
,'right'
, or'center'
). - label – Text label to show next to the colour bar.
- orientation – Either
vertical
orhorizontal
. - labelside – Side of the colour bar to put the label -
top
,bottom
,left
orright
. Iforientation='vertical'
, thentop
/bottom
are interpreted asleft
/right
(and vice-versa whenorientation='horizontal'
). - alpha – Colour bar transparency, in the range
[0.0 - 1.0]
. - fontsize – Label font size in points.
- bgColour – Background colour - can be any colour specification
that is accepted by
matplotlib
. - textColour – Label colour - can be any colour specification that
is accepted by
matplotlib
. - scale – DPI scaling factor.
- cmap – Name of a registered
-
fsleyes_widgets.utils.colourbarbitmap.
genColours
(cmap, cmapResolution, invert, alpha, gamma=1)¶ Generate an array containing
cmapResolution
colours from the given colour map object/function.