gribouillis2_pymui2.jpg Gribouillis2 is the successor of my first try to make a higly portable painting program.

Goals are:

  1. Highly portable
  2. Close to the host GUI toolkit
  3. Easy to modify
  4. Able to uses tablet specific features (pressure, tilt, …)
  5. Rich features like layers, undo/redo historic, multi-documents, and so on

gribouillis2_ellipse.jpg To reach them Gribouillis2 uses following technologies:

  • Python 2.x : (portability, easy modifications).
  • PureMVC : (like python, gives a framework for a graphic application, virualize the GUI toolkit used).
  • PyMUI : MUI Python binding (MorphOS)
  • PyGTK : GTK+ Python binding (others platforms)
  • PyCairo : (rendering, portability)


Gribouillis2 is designed to be simple: it's not (for the moment…) an image editor/manipulator. It takes some ideas seen since a long time on Amiga, but also on OS stamped modern, like Linux.
We'll find some similarities with following projects: ChibiPaint, DrawPile, FlowPaint, Krita, MyPaint and Qaquarelle.

Downloads and Installation

Current version is 2.7 (r333).

Standalones Binaries

Nothing more to install more than just unpack the archive1) on your hard-disk and run it!

Platform URI Size MD5
MorphOS Standalone - v2.7 r333 12.7MB 1de957c0071798fd0eb85bc008e93f8c
Linux Not available yet

Simple/Update Binaries

These versions contains only the code of Gribouillis itself and not dependencies.
So to use it you need to install them (described below).

Useful for updates or if you've already these dependencies installed on your system.

Platform URI Size MD5
MorphOS Simple - v2.7 r333 349.0kB 23d888eb15e00f60e635f4ffa771726d
Linux Not available yet


Sources are available as snapshot of the same revision used to generate binaries releases.
Only if you know how to build it yourself (eg. for other another platforms) or for you information ;-).

Sources - v2.7 r333 - 184.3kB
md5sum: 818f9a4dd53d2d5ea61bad45cf591618


Non standalone versions require following dependencies:



Bugs and limitations

(This category is only maintained for the current release and subject of changes).


  • Only OpenRaster (.ora) and PNG (.png) for saving, but loading is limited by the PIL formats support.
  • Pick mode (press 'p' on PyMUI port) takes color only from first layer.
  • CPU is often overloaded even with small brush.

PyMUI specific

  • Waiting for your feedback ;-).

PyGTK specific

  • Where is the release!

Technical aspects


Numerous others supposed cross-platform projects fail to reach this goal due to miss-understanding of used technologies. This is mostly seen for applications using graphic user interfaces (GUI).

Almost cross-platform projects try to find a toolkit adapted to the application's main language. This portable toolkits are written to expose the most common denominator between native GUI toolkits on each system.
Unfortunately most of the time these toolkits differs largely from each one, causing troubles and difficulties to keep nice API interface and system-friendly aspect in the same toolkit.
Except the language used, this is one reason of existence of so many portable GUI toolkits.

Consequence of this, toolkits don't try to expand to much their portability and limit their native support.
And for thus that don't try (like WxWidgets) to limit, porting them is a nightmare and even official examples are littered with platform conditional blocks to make them work.

So is another solution exists?
I think yes, I've found my solution just by using a not so young software design pattern knowns as MVC.
The idea is to apply the MVC rules stricly: user interface (UI) is loosely coupled of the functionality.
MVC stands for Model-View-Controler: This is not a new thing in software development, but this concept was never be used in a whole to separate platforms UI backends (aka the GUI toolkits).

So now the overall design is chosen, remains to find the language: Python is a good candidate!


  • Python tries to be multi-platforms and highly portable (even if I found its C implementation mostly designed for POSIX), and Python interpretor exists in many forms (C, Java, …).
  • Most of native toolkits have their binding in Python.
  • Python has a well documented C-API and the language is easily extensible using dynamic modules.
  • It's a script language, modifications don't need recompilation from clever maintainers.
  • An well-known simple MVC framework exists for Python: PureMVC.

Rich features

One of the main features of Gribouillis2 (other than it's true multi-platform design ;-)) is to not put limit to the drawing surface: you can always grow your image in all direction, it's border-less (excepted when saving obviously).





  • Add possibility to move a layer independently on the canvas (layer offset).
  • [in progress] Increase brush features and positional events handling.
  • More tools like mirrors?
  • More save file formats.
  • Save in 16bits than 8bits.
  • Add CYMK colorspace support.


The Future of Gribouillis2 (currently named Project GB3 until I found a suitable name):

Multiple views of the same document

1) Do not run Gribouillis from RAM: on MorphOS platform

en/dev/gribouillis2/start.txt · Dernière modification: 2011/03/06 17:06 par Yomgui