I'm trying to work out a way of printing plots as vector graphics that
use alpha channel.
I understand that postscript doesn't do alpha, so I was hoping to save
the plot as svg, import into illustrator and then save as a pdf and/or
print.
So I run the following file: (matplotlib svn 2943, os x, WXAgg back end)
from pylab import *
from numpy import *
rx, ry = 1.8, 1.
area = rx * ry * pi
theta = arange(0, 2*pi+0.01, 0.1)
verts = zip(rx/area*cos(theta), ry/area*sin(theta))
x = [0,0.1,0.2, 0.5,0.43]
y = [0.,0.1,0.,0.20,.2]
scatter(x,y, c='r', edgecolor='k', faceted=True, s=300, marker=None,
verts=verts, alpha=0.2)
y = array(y) + 0.01
scatter(x,y, c='g', edgecolor='k', faceted=True, s=300, marker=None,
verts=verts, alpha=0.2)
savefig('alpha_test.svg')
Unfortunately if I import alpha_test.svg into Illustrator or Inkscape,
the ellipses appear completely solid. Saving directly as .pdf produces
a solid image as well.
However, if I save the figure as .png, the ellipses are transparent.
I had the same problem running a slightly earlier version of
matplotlib on a Linux box with GTKAgg
Regards, George Nurser.
