first cut of the colorscheme-based focus support

plugin/pencil.vim

@@ -0,0 +1,45 @@
+" ============================================================================
+" File:        pencil.vim
+" Description: vim-colors-pencil plugin
+" Maintainer:  Reed Esau <github.com/reedes>
+" Created:     August 29, 2014
+" License:     The MIT License (MIT)
+" ============================================================================
+"
+if exists('g:loaded_colors_pencil') || &cp | fini | en
+let g:loaded_colors_pencil = 1
+
+" Save 'cpoptions' and set Vim default to enable line continuations.
+let s:save_cpo = &cpo
+set cpo&vim
+
+nnoremap <unique> <script> <Plug>ToggleFocus <SID>TogFocus
+inoremap <unique> <script> <Plug>ToggleFocus <ESC><SID>TogFocus<ESC>a
+vnoremap <unique> <script> <Plug>ToggleFocus <ESC><SID>TogFocus<ESC>gv
+noremap <SID>TogFocus  :call <SID>TogFocus()<CR>
+
+" a generic focus toggle, usable with any color scheme that supports it
+fun! s:TogFocus()
+  if !exists('g:colors_focus') || g:colors_focus == 0
+    set cursorline
+    set laststatus=0
+    set noruler
+    set scrolloff=999
+    let g:colors_focus = 1
+  else
+    set nocursorline
+    let g:colors_focus = 0
+  en
+  if exists('g:colors_name')
+    exe 'colorscheme ' . g:colors_name
+  en
+endf
+
+if !exists(':ToggleFocus')
+  com ToggleFocus :call s:TogFocus()
+en
+
+let &cpo = s:save_cpo
+unlet s:save_cpo
+
+" vim:ts=2:sw=2:sts=2