| Subject: | lines: patch to trim miter |
This patch is a primitive rewrite of the patch I did for GD::Graph3d::
lines3d.pm -- it is just here for compatibility. See also: http://rt.cpan.org/NoAuth/Bug.html?id=11734
I probably should have set the default to 1 there, and to 0 here.
thanks,
jw.
+=item trim_miter
+
+By default this is set to '1'. If line_width is large and trim_miter is +'0',
+typical zig-zag data lines may appear to exaggerated, due to the width of the
+lines. When trim_miter is set to '1', then acute-angled segments are cut back
+(with an additional small rectangle on top) to extend only half a line_width
+beyond the data points.
+
--- GDGraph-1.43/Graph/lines.pm.orig 2003-02-10 23:12:41.000000000 +0100
+++ GDGraph-1.43/Graph/lines.pm 2005-03-03 17:49:26.955087130 +0100
@@ -20,6 +20,37 @@
@GD::Graph::lines::ISA = qw( GD::Graph::axestype );
+my %Defaults = (
+ trim_miter => 1,
+);
+
+sub initialise()
+{
+ my $self = shift;
+ my $rc = $self->SUPER::initialise();
+ for my $k (keys %Defaults)
+ {
+ $self->{$k} = $Defaults{$k};
+ }
+ return $rc;
+}
+
+sub set
+{
+ my $self = shift;
+ my %args = @_;
+ for my $k (keys %args)
+ {
+ if ($k eq 'trim_miter')
+ {
+ $self->{$k} = $args{$k};
+ delete $args{$k};
+ next;
+ }
+ }
+ return $self->SUPER::set(%args);
+}
+
# PRIVATE
sub draw_data_set
@@ -147,14 +178,33 @@
# TODO: This loop probably should be around the datasets
# for nicer results
my $i;
+ my $lw2 = int($lw/2);
for $i (1..$lw)
{
- my $yslw = $ys + int($lw/2) - $i;
- my $yelw = $ye + int($lw/2) - $i;
+ my $yslw = $ys + $lw2 - $i;
+ my $yelw = $ye + $lw2 - $i;
- # Need the setstyle to reset
- $self->{graph}->setStyle(@pattern) if (@pattern);
- $self->{graph}->line( $xs, $yslw, $xe, $yelw, $style );
+ if ($self->{trim_miter})
+ {
+ ##
+ ## Not exactly a nice implementation of trim_miter.
+ ## The polygon approach of lines3d is superior.
+ ## At least it makes the lines as fat as expected
+ ## and naturally does trimmed mitering (by wasting CPU cycles).
+ ##
+ for my $j (1..$lw)
+ {
+ my $xslw = $xs + $lw2 - $j;
+ my $xelw = $xe + $lw2 - $j;
+ # Need the setstyle to reset
+ $self->{graph}->setStyle(@pattern) if (@pattern);
+ $self->{graph}->line( $xslw, $yslw, $xelw, $yelw, $style );
+ }
+ }
+ else
+ {
+ $self->{graph}->line( $xs, $yslw, $xe, $yelw, $style );
+ }
}
}
--- GDGraph-1.43/Graph.pm.orig 2003-07-01 07:02:10.000000000 +0200
+++ GDGraph-1.43/Graph.pm 2005-03-03 17:44:12.090345162 +0100
@@ -1290,6 +1290,14 @@
gaps, be careful when you use this.
Default value: 0
+=item trim_miter
+
+By default this is set to '1'. If line_width is large and trim_miter is '0',
+typical zig-zag data lines may appear to exaggerated, due to the width of the
+lines. When trim_miter is set to '1', then acute-angled segments are cut back
+(with an additional small rectangle on top) to extend only half a line_width
+beyond the data points.
+
=back
=head2 Options for graphs with points