Gruff with PDF::Writer

Rails
1

Hello all

Has anyone managed to embed gruff graphs into a PDF document using
pdf::writer?

The easy way (as far as I can see) would be to just save the gruff graph
as a temporary file then read that file in pdf::writer. I was wondering
if anyone had managed to get them working together directly?

RJ

2

I’m definitely looking for a solution to the same thing as well.

3

Bump…me too.

4

I did this pretty easily using the technique RJ described earlier
with writing a temp file. It’s kind of a hack but it works.

What I’m doing is:

First generating the gruff graphs and storing it as file, then
loading that file in as a blob in the db
Then generate the pdf by pulling the graphs out of the db, store them
as temp files, then load that file using the pdf image method.

Andy

5

There is a much easier workaround.
You may just set opacity to zero. Here’s how I did it:

require “gruff”
class Chart < Gruff::StackedBar
def opacity
@base_image.opacity
end
def opacity=( value )
@base_image.opacity = value
end

def draw
super
self.opacity = 0
end
end

Or, you may re-open the image and save it again:
g = Gruff::StackedBar.new( 640 )

…

i = unique_filename
g.write( i )

image = Magick::Image.read( i ).first
image.opacity = 0
image.write( i )

pdf = PDF::Writer.new
( pdf.image i ) && File.delete( i )