Transparent background for figures

I get the following warning in r2011a

set(gcf, 'Color', 'None')
Warning: Setting the ColorSpec to 'none' for a figure will not be allowed in a future release.

I use the "none" color so that I can print pdf and eps files with transparent backgrounds. How are you supposed to set a transparent background?

+1. I'd like to know about 'transparent'.

Answer 1

You can edit the eps file generated by print, and remove the line which creates the background rectangle, thus making the background transparent.

Or you can use the latest version of export_fig, which will do this for you when the -transparent option is specified, and will allow you to export to pdf as well.

Will take a look at how you edit the eps file in export_fig (and will likely accept your answer once I do). I still don't understand why the change in MATLAB was made.

I finally got a chance to dig around in export_fig. For those silly enough not to use export_fig, the line in the eps file can be found with: regexp(l, ' *0 +0 +\d+ +\d+ +rf *[\n\r]+', 'start').

Answer 2

Digging in the source of print I've found the colornone command in 2011b. It has a help section, but is not included in the local or net docs.

But the warning appears also. The print command simply disables the warning:

warning('off','MATLAB:hg:ColorSpec_None')

This does not look very trustworthy.

It seems odd that they are taking away functionality without providing a replacement. This usually means you are doing something odd. In this case, I don't think I am. My guess is that there will be a replacement by the time it is obsolete.

Note that this is not just a warning. The behaviour of print in R2011b has changed over R2011a. You cannot now save an eps or pdf with no background color, and TMW has provided no way around this (to my knowledge).

Answer 3

What do you mean transparent? Do you mean white background color? Would the pdf or eps file come out the same as set(gcf,'Color','None') as set(gcf,'Color',[1 1 1])?

I used to use whitebg(). But it's not really white background anymore since the default color is [.8 .8 .8]. whitebg() just turns it to [.3 .3 .3]. Same is the function colordef(). I

The benefit of a transparent background (as opposed to white) for printing is that if you overlay two figures with a transparent background the top figure doesn't block the bottom figure. With a white background you cannot stack figures. Similarly, if you are placing your figure on top of a background (e.g., in a poster, talk or lecture) the transparent background on the figure lets the poster background show through.

Okay, Thanks! When I tried set(gcf,'color','none') and export to an .eps file and then in MS Word, insert picture>From file, the front picture still blocks the view of the back picture. Why?

On the screen you see the TIFF preview. Does the blocking background concern the printout or an exported PDF also?

@Jan, I am using .eps file.
%%
plot(1:10);
set(gcf,'color','none');
saveas(gcf,'test.eps');

The test.eps only shows the axes. It doesn't show the margin we usually see in the MATLAB figure window.

MS Word used to do funky things with EPS files and the tiff preview. You might want to try powerpoint. Make a slide with a black background and import the figure. Even better is use something like inkscape/gimp/illustrator and play around with the eps file directly.

PowerPoint is the same. Anyway, I certainly can understand the difference between transparent and white. Thanks!

I just looked at your comments again more closely. You need:

set(gca,'color','none')

It's still the same for me, in MS Word or PowerPoint. In your question, shout it be gca or gcf?