From 4cb01c6bb768df0fc6a0116deec9d014a8f90b2d Mon Sep 17 00:00:00 2001
From: Tony Cook <tony@develop-help.com>
Date: Sat, 5 May 2012 14:24:35 +1000
Subject: [PATCH] [rt #59532] fix the zero position calculation for horizontal
 charts

also allow negative_bg to be a fill for horizontal charts
---
 lib/Imager/Graph/Horizontal.pm | 26 +++++++++++--------
 t/t14bar.t                     | 47 +++++++++++++++++++++++++++++++++-
 2 files changed, 61 insertions(+), 12 deletions(-)

diff --git a/lib/Imager/Graph/Horizontal.pm b/lib/Imager/Graph/Horizontal.pm
index 954cf9f..059f56f 100644
--- a/lib/Imager/Graph/Horizontal.pm
+++ b/lib/Imager/Graph/Horizontal.pm
@@ -167,10 +167,14 @@ sub draw {
     --$fill_box[3];
   }
 
-  $img->box(
-	    $self->_get_fill("graph.fill"),
-	    box => \@fill_box,
-	   );
+  {
+    my @back_fill = $self->_get_fill("graph.fill", \@fill_box)
+      or return;
+    $img->box(
+	      @back_fill,
+	      box => \@fill_box,
+	     );
+  }
 
   my $min_value = $self->_get_min_value();
   my $max_value = $self->_get_max_value();
@@ -178,17 +182,17 @@ sub draw {
 
   my $zero_position;
   if ($value_range) {
-    $zero_position =  $left + $graph_width + (-1*$min_value / $value_range) * ($graph_width-1);
+    $zero_position =  $left + (-1*$min_value / $value_range) * ($graph_width-1);
   }
 
   if ($min_value < 0) {
+    my @neg_box = ( $left+1, $top+1, $zero_position, $top+$graph_height - 1 );
+    my @neg_fill = $self->_get_fill('negative_bg', \@neg_box)
+      or return;
+
     $img->box(
-            color   => $self->_get_color('negative_bg'),
-            xmin    => $left+1,
-            xmax    => $zero_position,
-            ymin    => $top+1,
-            ymax    => $top+$graph_height - 1,
-            filled  => 1,
+	      @neg_fill,
+	      box => \@neg_box,
     );
     $img->line(
             x1 => $zero_position,
diff --git a/t/t14bar.t b/t/t14bar.t
index ebf1443..f426a0f 100644
--- a/t/t14bar.t
+++ b/t/t14bar.t
@@ -13,7 +13,7 @@ use Test::More;
 
 use Imager qw(:handy);
 
-plan tests => 7;
+plan tests => 11;
 
 my @warned;
 local $SIG{__WARN__} =
@@ -61,6 +61,51 @@ my @labels = qw(alpha beta gamma delta epsilon phi gi);
   cmpimg($img1, 'testimg/t14_bar.ppm', 80_000);
 }
 
+{
+  my $bar = Imager::Graph::Bar->new();
+  $bar->set_font($font);
+  ok($bar, "creating bar chart object");
+
+  $bar->add_data_series([ @data, -25 ]);
+  $bar->set_labels([ @labels, "neg" ]);
+
+  my $img1 = $bar->draw();
+  ok($img1, "drawing bar chart (negative values)");
+
+  $img1->write(file=>'testout/t14_bar3.ppm') or die "Can't save img1: ".$img1->errstr."\n";
+  #cmpimg($img1, 'testimg/t14_bar.ppm', 80_000);
+}
+
+{
+  my $bar = Imager::Graph::Bar->new();
+  $bar->set_font($font);
+  ok($bar, "creating bar chart object");
+
+  $bar->add_data_series([ @data, -25 ]);
+  $bar->set_labels([ @labels, "neg" ]);
+
+  my $fountain = Imager::Fountain->simple(colors => [ "#C0C0FF", "#E0E0FF" ],
+					  positions => [ 0, 1 ]);
+
+  my %fill =
+    (
+     fountain => "linear",
+     segments => $fountain,
+     xa_ratio => 0.5,
+     ya_ratio => -0.1,
+     xb_ratio => 0.55,
+     yb_ratio => 1.1,
+    );
+
+  $bar->set_negative_background(\%fill);
+
+  my $img1 = $bar->draw();
+  ok($img1, "drawing bar chart (negative values, custom fill)");
+
+  $img1->write(file=>'testout/t14_bar4.ppm') or die "Can't save img1: ".$img1->errstr."\n";
+  #cmpimg($img1, 'testimg/t14_bar.ppm', 80_000);
+}
+
 unless (is(@warned, 0, "should be no warnings")) {
   diag($_) for @warned;
 }
-- 
2.39.2