GSoC Ideas

From The Document Foundation Wiki
Jump to: navigation, search

This page lists the project ideas for Google Summer of Code, see the general info about LibreOffice and GSoC. Feel free to pick any of the tasks listed in the Programming Tasks section of the Easy Hacks page, but in that case you need to ask for mentors on the development mailing list if none is defined. Also the page the Genial Ideas page holds interesting ideas for a GSoC project, but – alike the EasyHacks page – you need to find a mentor for your GSoC project by asking on the LibreOffice developer list.

All tasks on this page already indicate mentors for the task. New tasks on this page should be added only by those with the experience and time to invest in mentoring new developers.

Note that the LibreOffice project selects GSOC projects that are well researched and show a good understanding of the scope of the problem. It is also possible to create a project proposal not based on the ideas given below, if the application of the student shows good understanding of the problem. In fact, if you apply with one of the prepared ideas below, we expect you to show you did research beyond the abstracts given below even more.

When doing that please use this template:


=== Title of the task ===

Some detailed description of the things to accomplish.
Don't hesitate to provide details if you have some like code pointers, links to specifications, etc.

;Required skills / knowledge: C++, Reading other's code, and any other useful skill required go here.

;Difficulty: Range among easy, medium, hard

;Potential mentors
:''Joe Devel'', IRC: jdevel, mail: joe@devel.org

Please move successfully completed projects to Development/GSoC/Successfully Implemented Ideas.

Contents

General

Refactor god objects

LibreOffice has quite a few huge god objects Wikipedia logo v3.svg , and it would be great to refactor them into smaller parts. sw/inc/doc.hxx was one included by half of sw and includes a huge loads of other headers. It was successfully refactored by Valentin Kettner in GSOC 2014. Apart from undesirable tight coupling, it also caused a major and unneeded increase in incremental (re-)build times. A successful proposal would need to have identified another god object beyond SwDoc and describe how and why LibreOffice would benefit from refactoring it. Note the availability of mentors by area of code below.

Required skills / knowledge
C++, Reading other's code
Difficulty
Medium
Potential mentors

writer:Bjoern Michaelsen, IRC: Sweetshark, mail: bjoern.michaelsen @ canonical.com

Analyse and optimize SfxItemSet, make it use a STL container internally

SfxItemSet is fundamental data structure heavily used while reading documents. It is also a very ancient, nonobvious container implementation. This task would be to analyse the use of SfxItemSet in default operations, for example:

  • How many slots does an average ItemSet have?
  • How much of an average ItemSet is usually filled?
  • How many read/writes does an ItemSet perform over its lifetime?
  • Could the SfxItemSet possibly gain from using Copy-On-Write?
  • ...

And then, depending on the results of this analysis, make the implementation a wrapper around an suitable STL container.

Required skills / knowledge
C++, callgrind, debugging
Difficulty
Hard
Potential mentors
Michael Stahl, IRC: mst[_]*, mail: mstahl AT redhat DOT com

More and better tests

While there are some automated tests for LibreOffice, there are not nearly enough. The goal here is to make developers who work on the code more productive by allowing them to find regressions as early as possible.

There is some support in LibreOffice for automated tests, both at the level of unit tests, and at the level of system tests that drive a full LibreOffice instance. Currently tests can be written in C++, Java, or Python. Various new automated tests should be developed to improve the test coverage.

Tests written exclusively for Java (eg. the JUnit framework) should be ported to C++ so that they can execute much more rapidly. Similarly, tests that do remote control of an existing LibreOffice instance, should be re-factored to run inside that instance to make debugging much easier.

Required skills / knowledge
Either C++, Java, or Python; for unit level tests reading other's code
Difficulty
Medium
Potential mentors
Michael Stahl, IRC: mst[_]*, mail: mstahl AT redhat DOT com

Reuse Mozilla's rolling update mechanism for LibreOffice tdf#68274

Mozilla is able to download the new installation on the background, patch itself, and restart. LibreOffice has its own mechanism for updates that does not allow this, unfortunately. This task is to re-use the code from Mozilla to provide the rolling update mechanism for LibreOffice too.

Most of the work was achieved during the GSoC in 2015; but still it is not in a state that it can be used by default for LibreOffice. The goal is to finish the work.

See also tdf#74934

Required skills / knowledge
C++, Reading other's code
Difficulty
Medium
Potential mentors
Jan Holesovsky, IRC: kendy, mail: kendy @ collabora . com

Expand Visual Studio (and others) to generate all executables/dlls

The python script "gbuild_to_ide", analyzes output from a makefile run and uses the information to generate among others project/solution files for visual studio.

Currently it only generates 7 of 25 executables and about half of the dlls. The analyzer needs to be expanded the missing connections. All information is available in the makefile output file, so this project is primeraly a visual analyze of the makefile output file, and then translate this into code.

Required skills / knowledge
python, base understanding of how make works
Dsifficulty
Medium
Potential mentors

jan iversen, IRC janIV, jani@documentfoundation.org

Unify low level text layout on HarfBuzz tdf#89870

Currently we use at least three different text layout systems (and half a dozen implementations of the SalLayout class) in VCL; Uniscribe on Windows, Core Text on Mac OS X and HarfBuzz everywhere else.

This have the advantage of being consistent with other applications on each platform (theoretically at least, since our integration code is often subpar). However, it has several disadvantages; first we need to maintain 3+ different text layout code paths with little sharing between them, which increases the complexity of our text layout code and platform-specific bugs and inconsistencies. We also are limited on Windows and Mac OS X by what both platforms provide in terms of complex text layout support, so we have don’t have the same language support on, say, Windows XP compared to Windows 10.

HarfBuzz is a free software text layout engine, it is actively developed and supported, both Firefox and Chrome switched to using it on all platforms to avoid the situations outlined above. LibreOffice would do the same and the existing HarfBuzz integration code would be generalised to be used on all platforms, phasing out and eventually dropping platform-specific alternatives.

Required skills / knowledge
C++, Reading other's code, Base understanding of text layout
Difficulty
High
Potential mentors
Khaled Hosny, IRC: KhaledHosny, mail: khaledhosny@eglug.org
Michael Meeks, IRC: mmeeks, mail: michael.meeks@collabora.com

Porting / platform / infrastructure specific topics

LibreOffice Online

LibreOffice online has developed significantly during the last year, but there is still a lot to do there. This task will include changes in the LibreOfficeKit, and in the web/JavaScript part too.

Required skills / knowledge
C++, JavaScript optional.
Difficulty
Medium
Potential mentors
Jan Holesovsky, IRC: kendy mail: kendy @ collabora.com

LibreOffice for Android

LibreOffice works nicely on Android these days, but there are stil many things to improve and fix. This task will focus on the Android Most Annoying Bugs:

https://bugs.documentfoundation.org/showdependencytree.cgi?id=84726

and also on new features, like printing.

Required skills / knowledge
C++, Java.
Difficulty
Medium
Potential mentors
Miklos Vajna, IRC: vmiklos mail: vmiklos @ collabora.co.uk
Tomaž Vajngerl, IRC: quikee mail: tomaz.vajngerl @ collabora.co.uk

Infrastructure for defining toolbars via .ui (Glade) files

The goal of this task is to create a new toolbar implementation that allows dynamic layout of widgets, and potentially tabbed toolbars too. Using that, it will be possible to easily define rich toolbars using Glade as the user interface designing tool.

What needs to be done:

  • Load toolbar definition(s) from .ui files
  • Create new custom widgets and C++ implementation for them
  • Implement mechanism to show/hide them depending on the context (Current application and currently selected object)
  • Improve the look of various widgets for their presentation in the toolbar (where necessary - like smaller padding around the widget etc.)
  • Implement priorities for widgets to allow dynamic hiding according to screen size

As we want to reuse as much of the existing code as possible, this work will heavily base on the Widget layout work and also on the sidebar implementation.

More tasks after the grounds have been laid:

  • Find a way to let the user customize the panels (like it is possible to customize the current Toolbar).
  • Extension integration: Allow extensions to add their own buttons/widgets to a panel

To get started, read the Sidebar code (sfx2/source/sidebar), and fix some Sidebar related bugs.

Code pointers
Required skills / knowledge
C++, Glade
Difficulty
Medium
Potential mentors
Samuel Mehrbrodt, IRC: samuel_m, mail: samuel.mehrbrodt@cib.de
Jan Holesovsky, IRC: kendy, mail: kendy @ collabora . com

User Interface

Revamp print dialog

Issues:

  • unclear workflow, e.g page format does not match printer settings

Bubli: "The main issue I have with status quo is this duality between "File -> Printer settings" and "File -> Print -> $some_printer -> Properties". In other words, settings of the printer and document/page-specific settings that can be (and often are) entirely different."

  • missing feedback in terms of a comprehensive overview of settings

(Changes have been made recently regarding blank pages. The existing option was challenged but kept for now.)

UI Concept:

Required skills / knowledge
C++, Reading other's code
Difficulty
High
Potential mentors
UX team, IRC: , mail: design @ global.libreoffice . org

Table of Contents: Entries tab

Issues:

  • Abbreviations hinder understanding of content → Entries should have the full text
  • Horizontal usage of space is cumbersome; we have much more room for vertical arrangement
  • Interactions are neither clear from layout nor the captions
  • Setting up entries and formatting/styling should get merged
  • Design is not appealing (at least the list with levels is too small)

UI Concept:

Required skills / knowledge
C++, Reading other's code
Difficulty
High
Potential mentors
UX team, IRC: , mail: design @ global.libreoffice . org

Special characters dialog

Issues:

  • There is no way to quickly re-use recently-picked special characters, forcing the user to search in the whole character map, which has no filter to narrow down results.
  • People writing scientific/legal essays or reports frequently need to insert accented letters and other characters.
  • Technical POV to special characters (alignment 15 by 15) instead of natural organization (e.g. letters A..Z in one line)
  • By presetting a font the subset is limited (some chars cannot be found when the wrong font is set-up)
  • Search function is missing (wanted by name, id, symbol…)
  • Cross-system reference not available
  • Weird interaction with selection first followed by copy/paste from Characters
  • No individualization like store last subset, or define ‘my own subset’

UI Concept:

Bug Reports:

Required skills / knowledge
C++, Reading other's code
Difficulty
High
Potential mentors
UX team, IRC: , mail: design @ global.libreoffice . org

Template Manager

Issues:

  • User initially sees a collection of folders that they have to go into in order to get to any templates
  • All templates from a particular app/module aren't available in one location
  • User can navigate into template folders that have nothing in them
  • OK/Open and Cancel buttons are not found at bottom of dialog as HIG recommends
  • UI feels more like a file manager when it should be focused on being a template browser
  • Template manager’s bad design causes problems with its integrated into the start center
Code pointers
UI Concept
Required skills / knowledge
C++, Reading other's code
Difficulty
Medium
Potential mentors
UX team, IRC: , mail: design @ global.libreoffice . org

Area fill

Issues:

  • Current tab is not intuitive due to its dynamic content
  • Controls are not appropriate to the function, e.g. color dropdown vs. color picker
  • Some of the newly introduced features for the sidebar are not available
  • tdf#94551: All-in-one Area tab for modifying object fill

UI concept:

Required skills / knowledge
C++, Reading other's code
Difficulty
Medium
Potential mentors
UX team, IRC: , mail: design @ global.libreoffice . org
Heiko Tietze, IRC: htietze, mail: tietze.heiko @ gmail . com
Yousuf Philips, IRC: jphilipz, mail: ypharis @ gmail . com

Table styles

Issues:

  • No common dialog
  • Style should be independent from the content (alternating rows)
  • No access from sidebar (either at styles/formatting or a sidebar for all table settings)
  • Similar workflow intended (sometimes) in Impress and Calc intended (Autoformat)
  • tdf#34391: Table Cell Styles / Table Styles
  • tdf#95279: Table content panel or tab

UI concept:

Required skills / knowledge
C++, Reading other's code
Difficulty
Medium
Potential mentors
Jan Holesovsky, IRC: kendy, mail: kendy @ collabora . com
UX team, IRC: , mail: design @ global.libreoffice . org
Heiko Tietze, IRC: htietze, mail: tietze.heiko @ gmail . com
Yousuf Philips, IRC: jphilipz, mail: ypharis @ gmail . com

Improve handling of AutoText

Libreoffice has very powerful AutoText features. But the handling is not userfriendly. not. Bug 50912, Bug 52607, Bug 52605, Bug 76295

However, since there is no UI concept yet interested students should ask for a UI concept first.

Required skills / knowledge
C++, Reading other's code
Difficulty
High
Potential mentors
UX team, IRC: , mail: design @ global.libreoffice . org

Bibliography dialog

Competitors reference managing is much better than what LibO offers. Existing solution need an updated GUI, and perhaps also support for the workflow.

However, since there is no UI concept yet interested students should ask for a UI concept first.

Required skills / knowledge
C++, Reading other's code
Difficulty
High
Potential mentors
UX team, IRC: , mail: design @ global.libreoffice . org

Review of the sidebar & its functionality

Many things in the sidebar are not finished yet, and also some of the modeless dialogs might provide much more value if they were sidebars; eg. the Insert -> Cross-reference... feels like a functionality that would fit to the sidebar; and for sure there are more.

Also there is prototype code for change tracking in the sidebar, finishing it would fit this task too.

Required skills / knowledge
C++, Reading other's code
Difficulty
Medium
Potential mentors
Jan Holesovsky, IRC: kendy, mail: kendy @ collabora . com
Katarina Behrens, IRC: bubli, mail: bubli @ bubli . org
Yousuf Philips, IRC: jphilipz, mail: ypharis @ gmail . com

Integration of the Templates Repository

As LibreOffice doesnt bundle may templates and the LibreOffice template community is vibrant, users who want access to templates will open their browser and visit the template repository, which isnt easy to navigate or search. So it would be a better user experience if the template repository was browseable in the template manager. The implementation should be implemented in a way that it is possible to browser and search different template repositories, with keeping the user interface the same between repositories.

UI concept:

Required skills / knowledge
C++, Reading other's code
Difficulty
Medium
Potential mentors
Jan Holesovsky, IRC: kendy, mail: kendy @ collabora . com

Rework of the Tools -> Customization... dialog

The current Customization... dialog could be much better organized, and could be have better. An extensive description is in http://user-prompt.com/how-to-make-libreoffice-customization-usable/, tdf#88896

Required skills / knowledge
C++, Reading other's code
Difficulty
Medium
Potential mentors
Jan Holesovsky, IRC: kendy, mail: kendy @ collabora . com
Katarina Behrens, IRC: bubli, mail: bubli @ bubli . org

Revamp the gallery tool

The LibreOffice Gallery tool would need to be enhanced to support features like sorting using tags, search, connection to online galleries like OpenClipart. This project aims at changing the gallery tool in this way. A previous GSoC project ended up with code for fetching and displaying pictures from OpenClipart. This code would need to be used as a basis for this project. As a later target, this new Gallery would be the base for an objects libraries dialog (eg network, UML...). Even though this would probably not fit in the time frame of a GSoC, this target may influence UI and code design choices.

The display of the galleries should be done as a side-bar, re-using the widget from Impress that has headings 'Master Pages' / 'Layouts' / 'Slide Design' etc. - but with each of these being a separate category of clipart - and presenting a selectable sub-set of these. This would make much better use of screen real-estate that the current horizontal gallery.

Here are some code pointers to get started in the task:

Required skills / knowledge
C++, Reading other's code
Difficulty
Medium
Potential mentors
Jan Holesovsky, IRC: kendy, mail: kendy @ collabora . com
Tomaž Vajngerl, IRC: quikee, mail: tomaz.vajngerl @ collabora . com

Application Themes

LibreOffice currently uses the OS's theme to color its menubar, toolbars, sidebar, statusbar, etc. but it would be useful for the user to be able to change this default feature. The Firefox Themes integration done in LO 4.0 by Jan Holesovsky and improved in LO 4.4 by GSoC 2014's Rachit Gupta were a step in the right direction but it wasnt a complete theme (e.g. theme background doesnt appear in toggled buttons, theme didnt change the color of the statusbar or scrollbars, theme didnt change the document color scheme, theme didnt change icon set, etc).

Proposal Info
https://docs.google.com/document/d/1J_aogLuQThqhvT0R2em27Vpew-SLAQgpH5TbNTgXPZM/edit?usp=sharing
Required skills / knowledge
C++, Reading other's code
Difficulty
Medium
Potential mentors
Jan Holesovsky, IRC: kendy, mail: kendy @ collabora . com

KDE4: use Qt4 widgets and abstraction layer for painting and event filtering

LibreOffices KDE4 VCL backend is just a shim layer around the X11 / Xlib VCL backend and next to TDE the only user. It provides a native file picker but otherwise just tryes to emulate the KDE look using low level paint methods. This results in multipe problems:

  • No platform abstraction; directly uses Xlib for drawing and event processing
  • No way to port to Qt5
    • Qt5 internally uses XCB, but the main problem is
      • QPixmap doesn't export the internal X11Pixmap anymore
      • No real way to do native X11 drawing - you want to use QPainter
    • You don't want to port an already dated X11 backend to XCB
    • The Cairo based Svp / headless VCL won't integrate well with Qt5, better use native QPainter
      • Cairo has a Qt / QImage based backend, but this can just use Qt4 or Qt5, as symbols clash and the backends are static and no loadable plugins
      • Would introduce a 2nd render path on Linux; you could probably start an implementing alternative Svp using QPainter?
    • No more native event filtering
    • No Wayland support
  • No modal native dialogs
    currently doesn't use QWidgets, so there is no way to implement the modal handling for the file picker. Gtk+ wraps the LO widgets in GtkWidgets, so modal native dialogs work.
  • No native widgets
    The KDE4 VCL plugin just uses some painting methods to render stuff, but there is some stuff we can't handle correctyl this way, like Oxygen menus. The Gtk+ plugin actually uses GtkWidgets to draw themself, giving a more native look and feel. Also it implements the SalMenu.
  • Slow painting,
    as all drawing operations are performed on a single image and copied using Xlib function. This image is always destroyed and there is basically no caching. Gtk+ keeps a caching widget per type around. This also isn't portable to Qt5
  • Use KIO internally
    Currently LO sets "X-KDE-Protocols=file,http,ftp,webdav". Even smb was included for some time. But actually this depends on the native load / save dialog settings, and even the VCL backend, because the KDE4 file picker / VCL backend doesn't support neither smb nor webdav without KIO.
TODOs
Documentation
see the next item KDE5: port KDE4 plugin to KF5
Code pointers
Required skills / knowledge
C++, Reading other's code
Difficulty
High
Potential mentors
Jan-Marek Glogowski, IRC: jmux, mail: glogow @ fbihome . de

KDE5: port KDE4 plugin to KF5

This work depends on the previous item KDE4: use Qt4 widgets and abstraction layer for painting and event filtering. After talking to KF5 developers, especially Martin Gräßlin, we concluded there wouldn't be much of a point to port KDE4 while it's based on X11 native Xlib calls.

Jmux comment: to get a better impression of the KF5 codebase and library layout I did an initial port, but this won't work, as it can't do any painting and the integration in the X11 event queue is also broken / commented out. If you really want to start this during a GSoC I would recommend you already know your way around KF5 + Qt5, or expect a steep learning curve.

TODO
Documentation
Code pointers
https://cgit.freedesktop.org/libreoffice/core/log/?h=private/jmux/kde5 (compiles but doesn't run)
Required skills / knowledge
C++, KF5 + Qt5, Reading other's code
Difficulty
Medium
Potential mentors
Jan-Marek Glogowski, IRC: jmux, mail: glogow @ fbihome . de

Base

Finish Firebird driver integration

Base's embedded database is currently an outdated copy/fork of HSQLDB 1.8, which holds us back because of data corruption issues (arising mainly from how the integration is done) and lack of features (because old copy that did not follow the progress of HSQLDB).

Rather than upgrade to a newer HSQLDB, it has been decided to switch to FireBird, mainly because of issues around depending on Java and performance issues with interfacing with Java in general.

The Firebird driver for LibreOffice was started, and is mostly functional, in a previous GSoC, but it needs finishing and polishing. The main remaining issue is that the firebird data format embedded in the .odb file is endianess-dependent. The idea is to switch to Firebird's "archive" format that is not.

Required skills / knowledge
C++, SQL, Reading other's code, capacity to work autonomously.
Difficulty
medium
Potential mentors
Lionel Elie Mamane, IRC: schoinobates, mail: lionel AT mamane DOT lu

Listbox separate read values from input values

A listbox acts as a mapping between values and display strings. The database (in general the value of the control) is one thing (drawn from the list content property), but the string shown to the user is another thing (drawn from the list entries property).

But these are actually used for *two* roles: - values read from the database - values input by the user

Sometimes, it is possible that the database contains values that the user should not be allowed to input. For example, historic / deprecated values, or more to the point the valid values depend on the value of other fields (or controls). One would then wish that the drop-down list feature only those values that are allowed in these particular circumstances.

The idea is to duplicate the "list entries" and "list contents" properties: - once for the role of mapping values read from the database(find what to display given a database value) - once for the role of mapping an entry chosen by the user to a database value (find what to write to the database when the user selects a list entry by its display string)

The idea is that the second set would in general be a subset of the first set, thereby giving the user a more limited selection for data entry, but still keeping the possibility of providing a user-friendly display string for other values read from the database.

How to handle listbox with Drop Down set to False is an open question.

Required skills / knowledge
C++, capacity to work autonomously.
Difficulty
medium
Potential mentors
Lionel Elie Mamane, IRC: schoinobates, mail: lionel AT mamane DOT lu

Outlook address book integration

Since LibreOffice 5.1 ancient SeaMonkey based Outlook address book integration feature is lost. See this announcement: https://wiki.documentfoundation.org/ReleaseNotes/5.1#Base.

With this project LibreOffice own MAPI driver should be provided that is based on restriction MAPI. This way both 32 bit and 64 bit Windows distribution would benefit from this integration.

Required skills / knowledge
C++, Visual Studio (2013 | 2015), reading existing code, capacity to work autonomously.
Difficulty
medium
Potential mentors
David Ostrovsky, IRC: _david_

Basic

Draw

Impress

Attach animations to styles

Currently, Impress styles control most of the visual shape appearance, but not the slideshow animation effect. Which is a pity, as the styles concept is pretty powerful inside LibreOffice, and provides a nice way to change animation settings and type for a great number of objects simultaneously. For a slightly different view onto the same problem, see this bug report, and this one from the LibreOffice side.

Original patch from GSoC 2010: https://cgit.freedesktop.org/libreoffice/build/tree/patches/dev300/sd_effects_styles.diff?h=master-backup

Required skills / knowledge
C++, Reading other's code
Difficulty
Hard
Potential mentors
Thorsten Behrens, IRC: thorsten, mail: thb @ documentfoundation . org
Katarina Behrens, IRC: bubli, mail: bubli @ bubli . org

Rework Impress slideshow to use DrawingLayer primitives

The Impress slideshow, while being designed to only interact with Impress via interfaces, had to resort to an ugly hack to be able to render all Impress content. That was ok back in the day, but is becoming a liability these days. Nowadays, what one want to use is the DrawingLayer Primitives (https://wiki.openoffice.org/wiki/DrawingPrimitives), which means porting over slideshow/source/engine/shapes/* to use this kind of abstraction, instead of the StarView Metafile previously in use.

Required skills / knowledge
C++, Reading other's code.
Difficulty
Difficult
Potential mentors
Thorsten Behrens, IRC: thorsten, mail: thb @ documentfoundation . org

SmartArt editing in Impress

At the moment, we are able to import SmartArt as a stream of shapes that is available in the pptx presentations generated by MSO 2010. We are also able to create the shapes when the stream is not available in case you enable the Experimental features Tools ▸ Options. Unfortunately:

  • The rendering of such shapes is much worse than if we use the pre-rendered stream
  • We are unable to edit the imported SmartArt

This task should first focus on improving the rendering of the shapes themselves, and then, when the student gets more familiar with the code, should add user interface for SmartArt editing.

The current experimental SmartArt import lives in oox/source/drawingml/diagram/*. The commit that introduced the functionality is Import SmartArt graphics to Impress.

Further information: The related bug in the LibreOffice bug tracker is: tdf#37932. An external extension (not nicely integrated) trying to implement at least some SmartArt functionality: SmART (Extensions/SmART Gallery)

Required skills / knowledge
C++, Reading other's code.
Difficulty
Difficult
Potential mentors
Muthu Subramanian, IRC: muthusuba, mail: muthu . subramanian . karunanidhi @ ericsson . com
Thorsten Behrens, IRC: thorsten, mail: thb @ documentfoundation . org

Mix and Merge Impress presentations

For the professional slide jockey, mixing a new presentation out of existing slide decks is a common task, that unfortunately Impress does not support very well. This task is about providing, possibly stand-alone, functionality to:

  • display lots of presentation files conveniently, possibly with tagging/searching functionality
  • out of existing slides, quickly create a new presentation
  • provide functionality to conveniently exchange / homogenize slide layouts and/or master pages, such that new presentation has consistent look
  • as a bonus task, be able to create virtual slide decks, by referencing other files, and have the resulting presentation automatically update, once the referenced slides are
  • can be built-in to Impress, stand-alone (but then portable across all our platforms), or web-based.

Code pointers:

Required skills / knowledge
ODF, UX, possibly c++, possibly Python, possibly web frameworks
Potential mentors
Thorsten Behrens, IRC: thorsten, mail: thb @ documentfoundation . org

Add Impress shape animations that use a real physics engine

Impress already sports a number of shape animation effects, though they start to look a bit dated in this day and age. With powerful 2D and 3D physics simulation engines available as open source, it would be cool to plug them for having slide contents interact with each other, bouncing around stuff on the screen. This task would involve:

  • integrating a suitably-licensed physics engine with LibreOffice (Box2D or Bullet come to mind)
  • interact with LibreOffice User Experience people on how to best present this in the UI
  • wire things up in the slideshow / canvas component of LibreOffice
  • be able to load and save the new effects, at least to odf files
  • in the end, have at least three effects ready to be used

Code pointers:

Required skills / knowledge
C++, basic game/animation skills useful, reading other people's code
Potential mentors
Thorsten Behrens, IRC: thorsten, mail: thb @ documentfoundation . org

Calc

Chart sheets in Calc

Currently Calc only supports table sheets ut for interoperability we should at least support chart sheets. For this task one needs to abstract the sheet handling in calc and adapt all places that unconditionally assume that every sheet is a table sheet.

Here are a few code pointers to this task:

Required skills / knowledge
C++, Reading other's code, debugging
Difficulty
Hard
Potential mentors
Markus Mohrhard, IRC: moggi, mail: markus.mohrhard@googlemail.com

Support ODF styles in orcus

Orcus is an external filter library for spreadsheet format that is used by LibreOffice. The library is mainly developed by one of the leading LibreOffice calc developers and already used for gnumeric import, the csv import in tests and optional odf and ooxml import. The support for styles is however still rudimentary but we would like to use it to support xml based pre-defined styles. The task would be to first add the odf styles support to orcus and then implement the corresponding interface on the LibreOffice side.

Required skills / knowledge
C++, Reading other's code, debugging

Difficulty: Easy to Medium

Potential mentors
Markus Mohrhard, IRC: moggi, mail: markus.mohrhard@googlemail.com

Implement interface for external data source import into Calc

With more and more data in different forms it becomes more and more challenging to visualize and evaluate them. Calc could be an amazing tool to allow inspecting existing data. To allow that we would need an interface to import and more importantly update data from external data sources. The interface should be modelled similar to how the orcus interface is currently implemented and the data should be stored inside of a ScDBData (a database range). The interface would then be used together with either an existing document where you mark a range for the external data or a template document that is automatically filled. Also as part of the task we should implement at least one provider of such data (for example a website with dynamic data) and the UI to handle that feature.

Required skills / knowledge
C++, Reading other's code, debugging

Difficulty: Medium to Hard

Potential mentors
Markus Mohrhard, IRC: moggi, mail: markus.mohrhard@googlemail.com

Support charts in orcus

Orcus is an external library for importing spreadsheet formats that is already used for a few features in Calc. However for now we are limited to spreadsheet support for now and we should extend support to charts. Orcus works by providing an interface of virtual methods that must be implemented on the client side. We try to keep the interface format independent and try to always support at least OOXML and ODF.

If the time permits we should also work on some experimental integration of the chart import code into LibreOffice.

The spreadsheet interface is mostly in include/orcus/spreadsheet. The chart interface should be similar.

Required skills / knowledge
C++, Reading other's code, debugging, Reading specifications

Difficulty: Medium

Potential mentors
Markus Mohrhard, IRC: moggi, mail: markus.mohrhard@googlemail.com

Writer

Improve VML import

The import of VML in our DOCX implementation is limited, and for example is unable to import rotation of ellipses, or shading of objects. Even though VML is not recommended by the OOXML specification as the format to use, MS Word 2007 uses that primarily, and as a consequence, there are many .docx files around using VML.

Here are some code pointers to get started in the task:

For sure there are missing rotations of shapes, or their shading. There will be a test document provided which is supposed to be imported perfectly after the end of the GSoC.

Required skills / knowledge C++, reading other's code

Difficulty: medium

Potential mentors:

  • Miklós Vajna, IRC: vmiklos, mail: vmiklos @ collabora . co . uk
  • Jan Holesovsky, IRC: kendy, mail: kendy @ collabora . com

Document Themes

Document themes are a simple way to allow users to quickly & consistently restyle the entire document. There is an implementation of this in MSO, and also Calligra plans to something in this regard, so this task actually consists of 2 parts:

  • Implementing user interface for the feature
  • Implement the ODF support for that

More ideas about the feature you can get by reading http://blogs.msdn.com/b/jensenh/archive/2006/02/22/537054.aspx and https://blogs.kde.org/2011/12/14/fruits-css2-shared-themes .

The import code for DOCX is here: https://cgit.freedesktop.org/libreoffice/core/tree/writerfilter/source/ooxml, you might need to change also https://cgit.freedesktop.org/libreoffice/core/tree/writerfilter/source/dmapper

For XLSX and PPTX, it resides in https://cgit.freedesktop.org/libreoffice/core/tree/oox/source

Required skills / knowledge
C++, Reading other's code, reading specifications :-)
Difficulty
Hard
Potential mentors
Jan Holesovsky, IRC: kendy, mail: kendy @ collabora . com
Tomaž Vajngerl, IRC: quikee mail: tomaz.vajngerl @ collabora.co.uk

Help system

Help display & indexing using JavaScript

Since the birth of OpenOffice.org, the help content has relied in a set of tools developed internally. In particular, the display of the help pages is done by a XSLT transform of XML files in a primitive own browser with very few graphic, multimedia and rendering resources.

The objective of this project is replace the local help application by displaying the local help directly in a web browser. To be able to do that, searching and indexing of the help pages has to be implemented in JavaScript.

Required skills / knowledge JavaScript, XML, reading other's code

Difficulty:

medium

Potential mentors:

  • Olivier Hallot, IRC: ohallot, mail: olivier.hallot@libreoffice.org
  • Jan Holesovsky, IRC: kendy, mail kendy@collabora.com

More information

https://wiki.documentfoundation.org/Help_Content_Modernization

Filters

Implement legacy StarOffice binary formats import filter

StarOffice 1.x - 5.x had a variety of binary formats which used to be supported by the notorious binfilter, which was removed in LO 4.0 since it was unmaintainable.

It should be possible to implement a much simpler import filter for the legacy StarOffice binary formats based on the librevenge import filter API. In the absence of file format documentation the source code for the binfilter can be used as a reference, but likely some reverse engineering and experimentation will also be required.

Required skills / knowledge C++, Reading other's C++ code (to reuse libwpd importer code and extract file format details from binfilter),

Difficulty: medium

Potential mentors:

  • Fridrich Strba, IRC: Fridrich, mail: fridrich.strba@bluewin.ch
  • David Tardon, IRC: dtardon, mail: dtardon@redhat.com

Implement Zoner Draw import filter

Zoner Callisto (known as Draw outside of the Czech Republic) is a very good vector graphics editor. After the development stopped, the last version (5) has been released free of charge (not open source, regrettably). This makes it a good choice for students etc. and increases the likelihood of appearance of files with .zmf extension. Therefore it would be great if LibreOffice could import it :-)

The goal is to implement a filter for (at least) version 5 of the format (there appear to be 2 variants of the format: one, based on OLE2, was used by versions 2 and 3; the other, which can be either zip or a single binary, by versions 4 and 5). No specification is available, but the most important parts of the file format have already been reverse engineered. Additional efforts to reveal details will be required.

The filter will be based on librevenge library.

Required skills / knowledge:

  • C++
  • Reading other's C++ code (to reuse libwpg/libvisio/libcdr/libmspub importer code)
  • Ability to understand hexadecimal dump of data
  • Ability to read (better yet, write) Python (for OLEToy)
  • Readiness to become famous

Difficulty: medium

Potential mentors:

  • David Tardon, IRC: dtardon, mail: dtardon@redhat.com

Implement EPUB export filter

EPUB is a widely-used open format for e-books. There are several extensions for OpenOffice.org (which presumably still work in recent LibreOffice) that can export it, but they appear to be mostly orphaned, with no update for years. Also, the output quality varies widely.

The goal of this task is to write an export filter for EPUB using the libepubgen library. The main part of the task will be conversion of text document model from UNO to librevenge API, but improvements to libepubgen are likely to be needed as well. The UNO->librevenge conversion will be generic, so it will be possible to reuse it for other export formats (e.g., to AbiWord format using librvngabw).

Required skills / knowledge:

  • C++
  • at least basic knowledge of EPUB / HTML / CSS
  • Readiness to become famous

Difficulty: medium

Potential mentors:

  • David Tardon, IRC: dtardon, mail: dtardon@redhat.com
  • Michael Stahl, IRC: mst_, mail: mstahl@redhat.com

Saving ODF XML of Change-Tracking as a sequence of predefined Changes

Document changes are able to be recorded via change-tracking. These changes can be revoked by returning to the previous state, which is being saved within the document's content XML. This is suboptimal as it does not allow overlapping changes, requires to load the complete document before becoming aware of the changes and is not compatible to state of the art real-time collaboration, where predefined changes are being exchanged. The OASIS ODF subcommittee of "Advanced Document Collaboration" is therefore specifying types of changes. The goal of this project is to adopt the ODF export filter to save recorded user changes as a sequence of these predefined changes.

Some documentation pointers are:

Required skills/knowledge: C++, working against specifications

Difficulty: medium to hard

Potential mentors:

  • Oliver Specht, mail: Oliver.Specht@cib.de
  • Svante Schubert, mail: Svante.Schubert@gmail.com

UNO

UNO is the LibreOffice component model, cross-language and intra- as well as inter-process. It is somewhat similar to Corba and COM. It is used to extend LibreOffice via document-related scripts and more general extension packages, as well as to use LibreOffice functionality remotely from another process.


Rust UNO Language Binding

UNO's cross-language abilities are implemented by bridging between various language-specific environments and a binary runtime representation (with a C API). Next to C++, Java, and Python, it would be great to have such a bridge also for a great language like Rust.

One aspect is to use Rust FFI to interface with the binary UNO C API. Another is to design the Rust representations of the various UNO constructs (its data types; objects with their multiple interfaces and methods; services and singletons), so that this language binding can not only be used to interact with existing LibreOffice services written in other languages, but also to create new services in Rust. A third aspect could be to create a pure Rust implementation of the UNO remote bridge protocol.

Some documentation pointers are:

Some code pointers are:

Required skills/knowldege: Rust, interfacing to low-level C/C++, working against formal specifications

Difficulty: medium to hard

Potential mentors:

  • Stephan Bergmann, IRC: sberg, mail: sbergman @ redhat . com
  • Michael Stahl, IRC: mst[_]*, mail: mstahl AT redhat DOT com

Tooling

Integrate .ui dialogs with translation tooling/string search webservice to help translators

Translators often have a hard time determining the context of a string to translate. It would be great if translators would be able to search for a string and have it presented in the context of the UI, a picture of a dialog for example.

Required skills / knowledge python (when integrating into pootle), java (when integrating into opengrok) or php or other suitable framework for the user-facing part, reading c++ code to identify where strings come from (not all strings are in dialogs) and GTK/glade ui definitions as the basis for the rendered dialog, scripting/makefile stuff to automate updating of the data

Difficulty: easy (when only limiting yourself to the glade dialogs) to medium (depending on the level of integration with the current tools: pootle as the platform where translation happens or opengrok where the source code is indexed)

Potential mentors:

  • Christian Lohmaier, IRC: cloph, mail: cloph@documentfoundation.org