Cavalcade of Mammals

Terminal colors are broken out of the box in OS X terminals. In part due to a poor OS X terminal implementation, part due to problems with vim. I try new colorschemes and get strange, random looking results.

After many fruitless searches I finally got 256 colors working in vim in a terminal. This post and the GVim site were very helpful. It turns out that the included Terminal app in OS X only supports 16 colors. The terminal background can be set to any color which confuses the issue. The colortest Perl script available on the Gvim site makes this clear.
OS X Terminal colortest:

The free GNU licensed iTerm terminal does support 256 colors.
iTerm colortest:

OK, now the terminal supports 256 colors. There are still some hoops to jump through to get vi to show colors though. Most colorschemes are built for gui (using 24-bit RGB colors), so vim needs to be built with gui support. This can be checked with :echo has(’gui’). It reports 1 for yes, 0 for no. The vim I had (default or Fink installed) didn’t have gui support, so I downloaded GVim and copied it over the old vim:

cp /Volumes/Vim-7.2.148/Vim.app/Contents/MacOS/Vim /usr/bin/vim

and now vim has gui support.

I copied /usr/share/vimrc to /usr/bin because the downloaded vim didn’t know to look in /usr/share and added a few configuration lines:

” Doesn’t get set right.
set t_Co=256

” Needed because the new vim doesn’t know to look in /usr/share
set runtimepath=~/.vim,/usr/share/vim/vim72_2,/usr/bin/vimfiles,/usr/bin,/usr/bin/vimfiles/after,~/.vim/after
let $VIMRUNTIME=’/usr/share/vim/vim72_2′

syntax on
colorscheme LightTan

OK, so now 256-color support works and I can set colorschemes. They still don’t look right because colorschemes made for the gui don’t look right on a 256-color terminal. There’s a great vim script called CSApprox that converts gui colors to the closest of the 256 colors and makes gui colors look pretty good in a terminal. Download it, unzip it, and copy files to the vim directory:
sudo cp plugin/CSApprox.vim /usr/share/vim/vim72_2/plugin
sudo cp autoload/csapprox.vim /usr/share/vim/vim72_2/autoload

and now when I load colorschemes they look pretty close to what the Vim colorscheme test site shows, with the only difference due to font differences.

To get full color support when I log into a linux machine I need to do some more setup. To get gui support in terminal:
yum install vim-X11
and then add to /etc/profile:
alias vi=’gvim -v’
and “source /etc/profile” to enable it.
and add:

set t_Co=256

if &t_Co == 256
colorscheme LightTan
endif

to /etc/vimrc to force 256-color mode and pick a colorscheme.

I also copied the CSApprox files to /usr/share/vim/vim70 and now it works when I ssh to this machine as well!

This entry was posted on Saturday, April 4th, 2009 at 2:32 pm and is filed under Computers. You can follow any responses to this entry through the RSS 2.0 feed. You can skip to the end and leave a response. Pinging is currently not allowed.