Transparent text with rmagick?


#1

hi -

(this maybe more an imagemagick q that a ruby one, but here goes …)

using rmagick / I have a small script for generating some type, but I
cannot get the type to come out as transparent png - it comes out just
on solid white .

does this have to be done with masks and compositing? there are a
number of methods that look like they should work (transparent_color
etc), but dont seem to…

is the library broken or am i doing something wrong?

tx,

/dc


require ‘rubygems’
require “RMagick”
include Magick

outfile = “output/matte.png”

drawObj = Magick::Draw.new
drawObj.font = ‘./fonts/Ghoul.ttf’
drawObj.pointsize=30
drawObj.fill = ‘#44ff00

buffer = Magick::Image.new(250,100)
drawObj.text(20,50, “hello world”)
drawObj.matte(3,3,PaintMethod::ReplaceMethod)
drawObj.draw(buffer)
buffer.opacity = 1
buffer.transparent_color = ‘#000000
buffer.matte = true
buffer.write(outfile)

system(“open #{outfile}”)

  David "DC" Collier

mailto:removed_email_address@domain.invalid
+81 (0)80 6521 9559
skype: callto://d3ntaku


#2

dc wrote:

etc), but dont seem to…

is the library broken or am i doing something wrong?

tx,

/dc
Set the background color to “none” when you create the image:

buffer = Magick::Image.new(250, 250) {self.background_color = ‘none’}