Google Summer of Code

Welcome to Inkscape!

For quite a few years Inkscape has been successfully participating in Google Summer of Code.

GSoC is a program where Google funds the development of specific features in open source software by university students. You don't need to be a Computer Science student to apply. Features to be developed are picked by Inkscape administrators from the pool of proposals submitted by students.

We've mentored about half a dozen students a year since GSoC started. Many students enjoyed their work and continue to be involved; perhaps your mentor will be a past GSoC student! We have a high rate of acceptance of student code into the core codebase. Indeed, GSoC projects have been a key source of some of Inkscape's best features in the past several releases.

If you are interested in joining us this summer, it is time to get your proposal ready. You can choose a proposal from our list of suggestions or come up with one of your own. In either either case, you must give us a detailed outline of what you plan to do. It is highly recommended that you discuss your idea as early as possible with Inkscape developers. They not only can give you guidance as you flesh out your proposal but ultimately you must convince them that you can do the work planned in the time allotted.

Student Applications

• Google program information:
  • Home page.
  • Summer of Code Application form. Applications open at 16:00 UTC on March 12th.

• Inkscape-specific information:
  • SOC Application Template.
  • Inkscape Roadmap - to see our overall objectives.
  • SOC Writing Project Proposals - some guidelines for proposals.
  • SOC Selection Criteria - how we rate applications.

Student Applications for GSoC 2018 must be submitted to the GSoC site by 16:00 UTC on March 27th 2018.

The "two patches" rule

We require two patches from each potential GSoC student, before accepting the student for GSoC participation (it is the same requirement as for obtaining rights to commit changes to the Bazaar code repository). The reason for this requirement is that you can show us that you have succeeded in building Inkscape on your PC, and that you have understood a little piece of Inkscape's code and are able to improve it. Inkscape is a large project, and you really should not try to understand all the code. Many (all?) developers know only parts of the program code! You can join our jabber/IRC channel and ask developers for help.

Suggested "easy" bug fixes or improvements

To get you started on Inkscape development, you can find (probably) easy-to-fix bugs or small improvements that require very little knowledge of the whole program by searching our bug-tracker for bugs tagged with 'easy-fix'.

Performance Evaluation

GSoC has two formal evaluation points, at the mid-term and at the end. These evaluations determine if you receive the stipend from Google. In order to receive a pass for the evaluations you will need to show adequate progress toward your project's goals.

To help you meet your goals and so that your mentor can better evaluate your progress you need to:

• Have frequent, public discussions of your progress. (Don't rely on just your mentor for advice.)
• Have a public Inkscape branch for your code to which you commit regularly.
• Give weekly status reports.

For the final pass, you will normally be required to merge your code into Inkscape trunk.

Remember: we want you to succeed!

Suggested Project Ideas

The following is a list of formal project suggestions, but do not feel limited to only these - some of our best contributions have been unique ideas that students had in mind from other sources!

See also Development Project Ideas, Refactoring projects, Projects, and https://blueprints.launchpad.net/inkscape/

P1. Better CSS Style Sheet Support

Enhance Inkscape's support for CSS style sheets.

• Estimation of difficulty: Moderately hard
• Potential mentors: Tavmjong Bah
• Programming skills needed: C++
• Prerequisites: Experience with CSS style sheets.

Detailed Description

Inkscape has rudimentary support for CSS style sheets that can read and parse one internal style sheet. A 2016 GSoC project added a simple style dialog that can create and modify the internal style sheet. The dialog is very limited and is not intuitive to use. This project will extend the usefulness of that dialog by making it more user friendly and by extending its functionality. The use of CSS classes should eventually replace the Selection Set dialog.

Stretch goals include:

• Support external style sheets. DONE
• Support multiple internal style sheets.
• Support CSS 3 selectors. DONE GSoC 2017
• Support parsing of 'font-face'. DONE

Use Cases

• Support externally created SVGs.
• Producing better SVGs for the Web.
• Changing style on multiple objects at once (palettes).

Related Material

• CSS 2 Specification
• CSS 2015 Snapshot

P3. Slice toolbar items

Example of result of the cut/eraser tool

Add slicing Live Path Effect (LPE)

• Estimation of difficulty: Moderately hard
• Potential mentors: Jabier Arraiza (Spanish, some English)
• Programming skills needed: C++

Detailed Description The goal is a LPE, to slice items.
It accept a path parameter as cutter.
The effect create pieces by the split path.
Add a toggle button to pause cutting on effect to allow move pieces cutted.
Add a option to reset pieces (reload LPE with the current path parameter).
We have the code of mirror symmetry LPE and rotate copies LPE as reference.
Also we can force or better ask to convert strokes to path previously to apply the effect (one line command, but we need advert is a destructive LPE)
Study autogenerate a HTML image map code linking with the Item LPE parameter to another object in hover state.
Use Cases

• Better item slicing.
• Split a item and use for example on PNG export option export as separate objects.

P4. SVG 2 Text Support (Done in GSOC 2017)

• Estimation of difficulty: Hard
• Potential mentors: Tavmjong Bah
• Programming skills needed: C++
• Prerequisites: Familiarity with text layout. Knowledge of CSS.

Detailed Description

Inkscape currently has a non-compliant flowed text feature (based on SVG 1.2 which was never adopted) that needs to be made compatible with both SVG2 and SVG 1.1. This project is to re-implement the flowed text feature within Inkscape to be SVG2 compliant and to have a proper SVG 1.1 fallback. In addition to the flowed text itself as it exists within Inkscape, SVG2 adds new formatting features including shape-margin and shape-padding, shape-inside and shape-outside, exclusions, additional white-space control settings, pre-wrap, pre-line, etc.

Use Cases

• Proper text flow into rectangles and other shapes.

Related Material

• Current draft of SVG 2 text specification.

P5. UI-Free Inkscape

• Estimation of difficulty: Moderate
• Potential mentors: Marc Jeanmougin
• Programming skills: C++, CMake
• Prerequisites: Minimal knowledge of build systems

Detailed Description Inkscape currently builds with X11 and gtk and a lot of graphical dependencies. But since it is allowed to run in commandline, and there are controlled environments (servers) that use it to convert svg to png and to perform actions, there should be no need to force it to build with those. The main goal of this project is to add a WITH_GUI compilation flag that when OFF, does *not* link Inkscape with any graphical dependency. Then action verbs should be checked and made independent from the gui (one should be able to use any action modifying the svg in --no-gui mode, which is not currently the case).

Stretch goal may include the transformation of said verbs to Gio::Action regular actions to ease gtk3 handling, and/or no-gui performance optimizations (currently Inkscape actions in commandline are slower than with gui).

Use cases

• Server installs, scripts

P6. Refactoring

• Estimation of difficulty: Moderate
• Potential mentors: Tavmjong Bah
• Programming skills: C++
• Prerequisites: proficient C++.

Detailed Description Inkscape began life as the C program Sodipodi. Sodipodi was mostly the work of one person who had a clear vision of how the code should work. A major motivation of the Inkscape fork was to allow others to easily contribute to development. This resulted in rapid development but at a cost: the code has become much messier and now lacks a clear vision. This project is to work on refactoring the code. Refactoring can take many forms. It could be creating a better directory structure with README's that describe the purpose and function of the code in each directory. This would include rewriting code to reduce dependencies across directories (which would help, for example, in achieving a headless version of Inkscape). It could be the continued transition from C to C++ which often results in major reductions in the number of code lines. Or it could be identifying and eliminating redundant code. Refactoring is an important skill of which many books have been written. Here's a chance to gain valuable experience!

P7. Polyfills

• Estimation of difficulty: Variable
• Potential mentors: Tavmjong Bah
• Programming skills: JavaScript
• Prerequisites: Experience in web development.

Detailed Description Many features of SVG 2 have yet to (and may never) make it into browsers. We can support those features by writing polyfills which implement missing functionality using JavaScript.

P8. Move from LivePathEffects to LiveEffects

• Estimation of difficulty: Hard
• Potential mentors: Jabier Arraiza (Spanish, some English)
• Programming skills: C++
• Prerequisites: Experience managing bitmaps

Detailed Description Live Path Effects are non destructive effects applied to paths and shapes standalone or inside a group.
This is done keepeng a reference to the original data to reaply when needed.
But ignore text and image elements.
Things to do:

• Refactor LPE system to rename it to LE.
• Study add image, text, both and maybe others SVG elements to the LE system.
• Create/adapt minimun one LPE for each new type of element acepted as reference. Suggestion Perspective-Envelope.

Use cases

• Apply live effects to images and text based in C++ code in a non destructive way: Slice, Mirror; Rotate, Perspective... even in groups with mixed elements types.

P9. Path Library Improvements

• Estimation of difficulty: Hard
• Potential mentors: Tavmjong Bah, KK
• Programming skills: C++
• Prerequisites: Strong math skills, specifically in geometry.

Detailed Description Inkscape relies on two geometry libraries for path manipulations: lib2geom and livarot. lib2geom is a generic modern library written specifically with Inkscape in mind. lib2geom is missing some functionality that Inkscape requires and that is found in livarot. This project is to move that functionality into lib2geom (or into separate files) using lib2geom path descriptions. Specifically, the functionality needed is

• Path offset/inset functions.
• Path simplify.
• Stroke to path function.
• Line scanning (used for flowing text into a shape).

P10. Your project

• Estimation of difficulty: Variable
• Potential mentors: Marc Jeanmougin
• Programming skills: usually C++
• Prerequisites: good ideas

Detailed Description The most successful GSoC we had in the past were students coming with their own past, use cases and ideas for Inkscape. Many basic tools like 3d cubes or connectors you can see in Inkscape now have been brought by brilliant people (like you) with ideas. If we think that your project fits with Inkscape (ie: has its place with a vector graphic editor), we can help you refining your ideas and help bring shiny new stuff to life!

Use cases

• Amaze us!

Successful SOC Projects from Previous Years

• 2005
  • Connectors
  • Inkboard
  • Open Clip Art Library (OCAL) Interface
  • DXF Import / Export
• 2006
  • Support for SVG Filters
  • Filter Effects
  • PDF export
  • Inkboard Protocol Spec / Lib Conversion
• 2007
  • Text Style Improvements
  • PDF import
  • Live Path Effects
  • 3D Box Tool
  • UI for SVG Filter Effects
  • Raster Functionality
  • Importing from, and Exporting to, a remote ccHost instance
• 2008
  • SVG Fonts support
  • 2Geom refactoring project - port most geometry code to 2Geom
  • lib2geom: interactive applications showing off the power of lib2geom
  • Tech drawing abilities
  • A test suite
• 2009
  • Node tool rewrite
  • D-Bus scripting API
  • Connector tool improvements
  • ICC/CMYK workflow
• 2010
  • Cairo-based rendering
  • C++ification of SP Layer
• 2011
  • Rendering caching
  • Javascript support improvements
  • CSS support improvements
• 2012
  • Usibility Improvements for Guides
  • On-canvas support for Tessellations
  • Creating python bindings for lib2geom
• 2013
  • Recolor Tool
  • Improved Units Support
  • Electronics CAD Support
  • New From Templates Dialog
  • New Raster to Vector Algorithm
• 2014
  • Better Support for SVG Paints
  • Robust Boolean and Stroking Operations for 2Geom
• 2016
  • Better data structure for selections
  • CSS Style Sheet Editor
• 2017
  • SVG 2 Text Support
  • Better CSS Style Sheet Support