From a38d857465c32035fa00a845c726785757b399a5 Mon Sep 17 00:00:00 2001
From: Tom Keffer <tkeffer@gmail.com>
Date: Fri, 27 Jan 2023 05:22:45 -0800
Subject: [PATCH] Allow line_gap_fraction to be used with bar plots.

Fixes issue #818.
---
 bin/weeplot/genplot.py      | 10 +++++-----
 bin/weewx/imagegenerator.py | 23 ++++++++++++-----------
 docs/changes.txt            |  2 ++
 3 files changed, 19 insertions(+), 16 deletions(-)

diff --git a/bin/weeplot/genplot.py b/bin/weeplot/genplot.py
index b22cd9e0..83b2d349 100644
--- a/bin/weeplot/genplot.py
+++ b/bin/weeplot/genplot.py
@@ -1,5 +1,5 @@
 #
-#    Copyright (c) 2009-2021 Tom Keffer <tkeffer@gmail.com>
+#    Copyright (c) 2009-2023 Tom Keffer <tkeffer@gmail.com>
 #
 #    See the file LICENSE.txt for your full rights.
 #
@@ -366,8 +366,8 @@ class GeneralPlot(object):
 
             # Calculate the size of a gap in data
             maxdx = None
-            if this_line.gap_fraction is not None:
-                maxdx = this_line.gap_fraction * (self.xscale[1] - self.xscale[0])
+            if this_line.line_gap_fraction is not None:
+                maxdx = this_line.line_gap_fraction * (self.xscale[1] - self.xscale[0])
 
             if this_line.plot_type == 'line':
                 ms = this_line.marker_size
@@ -611,7 +611,7 @@ class PlotLine(object):
     """Represents a single line (or bar) in a plot. """
     def __init__(self, x, y, label='', color=None, fill_color=None, width=None, plot_type='line',
                  line_type='solid', marker_type=None, marker_size=10, 
-                 bar_width=None, vector_rotate = None, gap_fraction=None):
+                 bar_width=None, vector_rotate = None, line_gap_fraction=None):
         self.x               = x
         self.y               = y
         self.label           = to_text(label)   # Make sure the label is in unicode
@@ -624,7 +624,7 @@ class PlotLine(object):
         self.width           = width
         self.bar_width       = bar_width
         self.vector_rotate   = vector_rotate
-        self.gap_fraction    = gap_fraction
+        self.line_gap_fraction = line_gap_fraction
 
 
 class UniDraw(ImageDraw.ImageDraw):
diff --git a/bin/weewx/imagegenerator.py b/bin/weewx/imagegenerator.py
index 284dbcf6..3689582e 100644
--- a/bin/weewx/imagegenerator.py
+++ b/bin/weewx/imagegenerator.py
@@ -1,5 +1,5 @@
 #
-#    Copyright (c) 2009-2021 Tom Keffer <tkeffer@gmail.com>
+#    Copyright (c) 2009-2023 Tom Keffer <tkeffer@gmail.com>
 #
 #    See the file LICENSE.txt for your full rights.
 #
@@ -255,6 +255,10 @@ class ImageGenerator(weewx.reportengine.ReportGenerator):
             # Get the type of plot ('bar', 'line', or 'vector')
             plot_type = line_options.get('plot_type', 'line').lower()
 
+            if plot_type not in {'line', 'bar', 'vector'}:
+                log.error(f"Unknown plot type {plot_type}. Ignored")
+                continue
+
             if aggregate_type and plot_type != 'bar':
                 # If aggregating, put the point in the middle of the interval
                 start_vec_t = ValueTuple(
@@ -302,7 +306,7 @@ class ImageGenerator(weewx.reportengine.ReportGenerator):
             width = to_int(line_options.get('width'))
 
             interval_vec = None
-            gap_fraction = None
+            line_gap_fraction = None
             vector_rotate = None
 
             # Some plot types require special treatments:
@@ -313,15 +317,12 @@ class ImageGenerator(weewx.reportengine.ReportGenerator):
             elif plot_type == 'bar':
                 interval_vec = [x[1] - x[0] for x in
                                 zip(start_vec_t.value, stop_vec_t.value)]
-            elif plot_type == 'line':
-                gap_fraction = to_float(line_options.get('line_gap_fraction'))
-                if gap_fraction is not None and not 0 < gap_fraction < 1:
+            if plot_type in ('line', 'bar'):
+                line_gap_fraction = to_float(line_options.get('line_gap_fraction'))
+                if line_gap_fraction and not 0 <= line_gap_fraction <= 1:
                     log.error("Gap fraction %5.3f outside range 0 to 1. Ignored.",
-                              gap_fraction)
-                    gap_fraction = None
-            else:
-                log.error("Unknown plot type '%s'. Ignored", plot_type)
-                continue
+                              line_gap_fraction)
+                    line_gap_fraction = None
 
             # Get the type of line (only 'solid' or 'none' for now)
             line_type = line_options.get('line_type', 'solid')
@@ -344,7 +345,7 @@ class ImageGenerator(weewx.reportengine.ReportGenerator):
                 marker_size=marker_size,
                 bar_width=interval_vec,
                 vector_rotate=vector_rotate,
-                gap_fraction=gap_fraction))
+                line_gap_fraction=line_gap_fraction))
 
         # Return the constructed plot if it has any non-null data, otherwise return None
         return plot if have_data else None
diff --git a/docs/changes.txt b/docs/changes.txt
index 796bea25..7019666c 100644
--- a/docs/changes.txt
+++ b/docs/changes.txt
@@ -25,6 +25,8 @@ Added new unit "hertz". PR #812. Again, thanks to user Karen!
 Calculate `*.wind.maxtime` out of `windGust` like `*.wind.max`
 Fixes issue #833
 
+Option line_gap_fraction can now be used with bar plots. Fixes issue #818.
+
 
 4.9.1 10/25/2022
 Fix problem with `wind` for older versions of sqlite.