diff --git a/lib/Slic3r/Config.pm b/lib/Slic3r/Config.pm
index 4ccb6bca..06185ad1 100644
--- a/lib/Slic3r/Config.pm
+++ b/lib/Slic3r/Config.pm
@@ -5,8 +5,6 @@ use utf8;
 
 use List::Util qw(first);
 
-use constant PI => 4 * atan2(1, 1);
-
 # cemetery of old config settings
 our @Ignore = qw(duplicate_x duplicate_y multiply_x multiply_y support_material_tool);
 
diff --git a/lib/Slic3r/Fill/Base.pm b/lib/Slic3r/Fill/Base.pm
index dec81199..546d914a 100644
--- a/lib/Slic3r/Fill/Base.pm
+++ b/lib/Slic3r/Fill/Base.pm
@@ -1,14 +1,13 @@
 package Slic3r::Fill::Base;
 use Moo;
 
+use Slic3r::Geometry qw(PI);
 
 has 'print'               => (is => 'rw');
 has 'layer'               => (is => 'rw');
 has 'max_print_dimension' => (is => 'rw');
 has 'angle'               => (is => 'rw', default => sub { $Slic3r::Config->fill_angle });
 
-use constant PI => 4 * atan2(1, 1);
-
 sub angles () { [0, PI/2] }
 
 sub infill_direction {