1. Yoann Padioleau (Facebook) http://github.com/facebook/pfff
CodeMap Google Maps for Source Code
Yoann Padioleau (Facebook)

2. About this talk Feel free to ask questions during the talk
Disclaimer: I do not represent Facebook

3. Problem
Dealing with huge codebase is difficult for noobs or new employees. Typical questions:
What are the important functions in big API?
What are the entry points?
What is the big picture?
Spend time mostly reading/understanding code, not so much writing new code.
Not too bad for linux, books
Tools to assist reading and understanding code?

4. Recent technological changes
Huge monitors, 30’
Often have multiple ones
Very high resolution (2600 x 1700)
But we still use 80-columns based editors
Or Eclipse which provides very few pixel for the actual code …
Can we leverage all those pixels?

5. Codemap Approach Focus on assist reading/understanding code
Program analysis + information visualization
Google maps metaphor
Zoom in/out
Important stuff should be bigger

6. Demo

7. Features Big picture, treemaps, “macro level” Search, navigation
Semantic-based code highlighting “micro level”
Connection to editor (emacs/vim)
Extensible via layers (predator mode)
Smooth transition from macro ti micro
Codemap is not an editor

8. Features: treemap Each rectangle is a file
Size of rectangle =~ size of file
Color of rectangle = “aspect” (test, main, storage, security, etc)
“Code aware” (heuristics)
Auto generated file do not eat real-estate
Code is more important than data, xml, jpg
Tiling, use all the space

9. Features: search and navigation
Highlighted rectangle
Ranked entities
Navigation
Up/down (not as smooth as google maps)
Direct access to file (faster than speedbar or expand-directory widgets)
Can see spread directories

10. Features: semantic code visualizer
grammar-based highlighting, not regexps as in emacs/vim
Know records vs functions vs constants
Functions/classes are in bigger size than statements
Tiling, use all the space, multi columns
Semantic aware (global analysis)
Important functions are in bigger size
(if fontsize too small to fit the all file on a 30’ => split file)
fast load of structure of the file in the brain

11. Layers: alternate color schemes
Age (help find dead code)
#authors (important stuff usually)
Activity (what’s going on?)
Code coverage
Bugs/warnings of linter
grep/sgrep results
Top/Bottom modules …

12. $ git clone git://github.com/facebook/pfff.git
Conclusion
A semantic-based source code visualizer/searcher/navigator
Accelerate loading the code into your brain (can see 20 files at once)
Future work:
Web UI, LXR 2?
Smoother zoom
Module/package dependencies
$ git clone git://github.com/facebook/pfff.git

13. Related work SeeSoft (does not scale, no treemaps)
Code Thumbnails (2 different modes)
3d visualization (not sure it helps, eat pixels)
Disk explorer (not code aware, no micro-level)
No smooth transition, 2 worlds.