TODO

Upgrade:
    - It seems Fitz has become much more multi-thread friendly now we've reached
      MuPDF 1.11. We might even be able to completely remove the Big Fitz Lock.

Fixes:

    - Check commit a154a6b and the one before that for proper mupdf 1.3
    compatibility. Mainly the drop/free display lists.


Backend:
    -   Write API for multiple graphical frontends
    -   Text selection & searching.

    -   Annotations:
        -   

    -   On demand rendering / pixmap cache.

fbcon support (with sdl)!

SDL/GL Frontend:
    -   Smooth scrolling [DONE]
    -   Dragging with RMB [DONE]
    -   Scrolling with arrow keys [DONE]
    -   Scrolling with wheel [DONE]

    -   Scrolling horizontally when we implement zoom. [TODO]

    -   Text selection [TODO]
        -   Hyperlinks

    -   Page markers (like vim) [TODO]
    -   Vim-like keys. [0..9*][h,j,k,l] [PARTIALLY]
    -   Text search. (With '/') [TODO]

    -   Annotations: [TODO]
        -   Turn on/off annotation hints
        -   Hover over annotation to completely see it? Render the text
        somewhere else?

    -   Options frontend. (Drop down menu, a-la Quake) [TODO]
        -   Semi-transparent.
        -   Python scriptable? (then we probably need to write a huge part in
        Python - may be a good idea)

    -   Chapter overview.

SDL/GLES Frontend: ( http://wiki.meego.com/SDL_Gles )
    -   Largely the same as SDL/GL, but requires some different GLES commands.
        [TODO]

Android Port: ( http://jiggawatt.org/badc0de/android/index.html#sdl )

Frontend:
    -   GTK 2D frontend.
    -   Firefox plug-in using NPAPI.

View modes:
    -   Multiple pages per row.
    -   ``Book'' mode. (two pages visible, next page chooses the two next pages)
    -   Presentation mode. (Perhaps smooth effects, one page visible at any time)
    -   ``Overview'' mode.