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This page contains a list of open tasks. Completing any of them would benefit the ScummVM project a lot. At least in theory, all of them should be doable even by somebody relatively new to the project, in particular, as part of the Google [[Summer of Code]]. Besides the tasks listed here, there is of course also the [[TODO]] page listing more things that need to be done (but with far less details).
'''See [[GSoC Ideas]] if you're looking for Google Summer of Code ideas for 2014.'''


TODO: All of these need to be explained with more detail, in proper english sentences!
'''See [[ClosedTasks|Closed Tasks]] for a list of tasks proposed the previous years'''


== Improved plugins code ==
''Technical Contact'': [[User:Fingolfin|Max Horn]]


ScummVM contains by now over a dozen different engines for different adventure game systems. Each of these engines forms a "plugin", and it is possible to compile these plugins as loadable modules separate from the core of ScummVM itself. This makes it possible to (un)load engine code at will, ideal for systems with tight memory constraints; if you want to play a game, you only need to load the engine for that specific game, and can unload the others.
<!-- This page contains a list of substantial open tasks from throughout the project. Completing any of them would be of great benefit to the ScummVM project.  


We always compile the engines as "plugins", but by default, they are compiled as so-called "static" plugins; these are not real plugins, but rather the engine gets compiled into the application (i.e. "static linked", hence the name), but is still treated by the rest of the application as a plugin (only that it is not dynamically loaded). Support for true "dynamic" plugin is only available on a subset of all plugins -- essentially most POSIX systems (including Linux, *BSD, Mac OS X) and the Dreamcast.
In theory, all of these tasks should be doable even by somebody relatively new to the project, in particular, as part of a Google [[Summer of Code]] project.  


There are various ways in which this plugin code could be improved:
It should be noted however that while we suggest that potential GSoC students looks at these tasks they are in no way exclusive to GSoC. Anyone is very welcome to work on any task (or any aspect of it).
* Add support for real "dynamic" plugins on Windows. This is currently not possible, because the ScummVM plugins rely on "backlinking" from the loaded modules to the core binary. This is not supported on Windows. There are various ways to solve this issue (use Google for more info). This is further complicated by the fact that while the interface of the *plugins* is well-defined (although not quite as well documented -- see base/plugins.h), the converse is not true -- plugins can call virtually arbitrary code within the core of ScummVM
* Add support for "dynamic" plugins on more systems which might benefit from them.
* Improve the way we search for plugins. Right now we only look in the current directory. Should this be made configurable? On Unix, maybe /use/share/scummvm should be searched, too? On Mac OS X, the CoreFoundation bundle API should be used to search for plugins inside the ScummVM.app bundle (which would also required the build system to be enhanced to properly bundle all plugins). Etc.


== Small devices backend  ==
Besides the tasks collected here, there are of course also the [[TODO]] pages listing more things that need to be done (but with far less details).
''Technical Contact'': [[User:Sev|Eugene Sandulenko]], [[User:Fingolfin|Max Horn]]


ScummVM has been ported to many platforms, often by simply re-using the SDL backend (which is based on [http://www.libsdl.org SDL], which by itself has been ported to many platforms, making it fairly easy to port ScummVM to any of these platforms, too).
__TOC__


But for some [[Platforms|platforms]], dedicated backends are required, either because SDL doesn't support them, or because we can't achieve all our needs by using the SDL port (e.g. because we need more speed, more control, etc.). These backends are typically made for what we call "small systems" -- systems like PDAs or smartphones (PalmOS, Symbian, WinCE), or game consoles (Dreamcast, GP2X/GP32, Nintendo DS, PlayStation 2, PlayStation Portable). These systems share many features. In particular they often have no (full) keyboard and quite limited resources: Little RAM, little permanent storage space, not that much CPU power, or a limited screen resolution.
== Introduction ==
=== Some basic rules ===


This makes it often necessary to (re)implement certain functionality, like virtual keyboards, or graphic downscalers. Since the same needs occur again and again, it would be nice to implement such functionality only once in a sufficiently portable and flexible way, making it possible for backends to pick and use whatever they need. Details and further suggestions as to how to achieved this can be found on the [[Small Devices Backend]] page.
Below follow some basic rules that anybody interested in one of these tasks should adhere to. Sometimes exceptions may be possible -- as always, common sense applies, and if in doubt, ask.


Besides this, optimizing code for speed and memory usage benefits all our targets, and in particular these "small devices". Hence doing this is a worthy goal on its own.
The projects below are sketches and ideas. Plus, things evolve over time, so the descriptions might be slightly outdated by the time you read them (although we strive to keep them up-to-date). Hence, you should talk with somebody from the team, probably the person(s) listed as Tech Contact, before starting work on any of them.


== Enhance FilesystemNode system ==
All code, unless stated differently, must be written in clean and portable C++, in particular, GCC must be able to compile it (portability exceptions can be made for platform specific code, of course). We also have some [[Code Formatting Conventions]]. Using the standard C++ lib for code used inside ScummVM is at this time not possible. Using it inside a non-essential tool should be fine, though.
''Technical Contact'': [[User:Fingolfin|Max Horn]]


ScummVM run on a great variety of platforms, ranging from full-blown personal computers running Windows, Linux,  Mac OS X, etc.,  to game consoles, smart phones and PDAs (sorry, no support for toasters yet :).
All of the code submitted must be contributed under the terms of the GPL v2+.


To achieve that, we have to provide abstract APIs for many things, like audio and graphics, user input, and general I/O. One particular area that needs to be covered are filesystems -- great differences exist with regards to this between the platforms we support. In fact, some of them don't even have such a thing as a filesystem.
We only accept clean and maintainable code. This is a somewhat vague requirement, but as a rule of thumb, if the code does what it is supposed to do, but is not extensible, a quick hack, or we need to rewrite it from scratch to properly integrate it, we will not accept it. In particular, we would rather have a maintainable, clean and incomplete piece of code that we could extend than a complete but unmaintainable piece of code.


Still, we need to access files: We have to find and load the game data, GUI themes, savestates, config files and more (and also have to store savestates, obviously). To compensate for the differences between our target systems, we introduced the FilesystemNode API.  
=== Some good advice for [[Summer of Code]] Applications ===
The PostgreSQL folks have some real good
[http://www.postgresql.org/developer/summerofcodeadvice.html Advice to Students on Submitting GSoC Applications]. We recommend all students interested in applying with us (or any other GSoC project, for that matter) to read this.


In its present state, it fulfills our absolute minimal requirements. However, the abstraction level it provides is flawed and likely should be overhauled / redesigned. Also, not all parts of ScummVM strictly use this API; there are still many parts of ScummVM which try to work with "paths" to access file data.
==== Student application template ====
The following was adapted from the FreeBSD [http://www.freebsd.org/projects/summerofcode.html Proposal Guidelines].


To work on this, you should be familiar with at least Windows and Unix, ideally more, and be willing to learn about the differences between file systems on many different platforms (our team will be happy to help you with this). You will have to design a revised FilesystemNode API, and implement it, based on the needs of ScummVM engines and infrastructure code (requiring close communication with the rest of the team).
* '''Name'''
* '''Email'''
* '''Project Title'''
* '''Possible Mentor''' (optional)
* '''Benefits to the ScummVM Community''' - A good project will not just be fun to work on, but also generally useful to others.
* '''Deliverables''' - It is very important to list quantifiable results here e.g.
** "Improve X modules in ways Y and Z."
** "Write 3 new man pages for the new interfaces."
** "Improve test coverage by writing X more unit/regression tests."
** "Improve performance in FOO by X%."
* '''Project Schedule''' - How long will the project take? When can you begin work?
* '''Availability''' - How many hours per week can you spend working on this? What other obligations do you have this summer?
* '''Skype ID''' - If you don't use Skype, install it.
* '''Phone Number''' - Cellular is preferable, for emergency contacts.
* '''Timezone''' - Where do you live.
* '''Bio''' - Who are you? What makes you the best person to work on this project?


== GUI ==
== Your task ==
''Technical Contact'': [[User:Sev|Eugene Sandulenko]], [[User:LordHoto|Johannes Schickel]]


ScummVM implements its own GUI code. We can't use any of the portable GUI kits out there, as they are mostly not portable enough, use too many resources, or simply are not flexible enough to work atop our backend system. Also, our GUI must look equally good with 8bit, 16bit or 32bit graphics, at 320x200, 320x240 or 640x480 resolutions -- and ideally also at 240x200 or at 1280x1024.
=== Anything you can dream of ===
''Technical Contact'': Our IRC channel, our mailing list, or contact [[User:Sev|Eugene Sandulenko]], [[User:DJWillis|John Willis]]


Currently we have a quite flexible system for defining the look and feel of our GUI. Almost every aspect of it can be specified via external theme file desribed [[GUI_Themes/Specs|here]].
''The Task:''


However there are many things missing:
Come up with your personal clever way to improve ScummVM and its various side projects. Be creative. Incorporate the ideas listed below and in our [[TODO]], but don't let yourself be limited by them. Come up with something totally new, or enhance existing features. It's up to you.


* Shadows are not configurable
But of course like with all the other tasks, we recommend that you first talk to us (see above).-->
* Not all widget aspects such as font to use are configurable
* We need to implement possibility for backends to extend GUI by adding their own tab in options dialog
* It would be nice to have antialiased fonts (possibly optionally -- we still need to support relatively low end devices, after all)
* Perhaps implement portable support for TrueType fonts
* We need better About dialog
* There are [[GUI_Themes/TODO|a number]] of small things to do which will make GUI behavior more predictive
* Modern Theme renderer should be reworked to make it faster, for example currently shadow drawing is rather slow (and hacked)


== Revive ScummEX (likely from scratch) ==
== Current Open Tasks ==
ScummEX (short for "Scumm EXplorer") is a tool which allows browsing the data files of games supported by ScummVM. That's the theory. Current reality is that the ScummEX version in our Subversion repository only supports a subset of SCUMM games (i.e. not even all SCUMM games, not even talking about *all* games supported by ScummVM). It also is based on an old version of wxWidgets, and written in a rather crude way. Hence, starting from a clean new code base likely is the best way to approach this.


So the goal of this would be to write a new graphical tool which allows browsing of data files of games supported by ScummVM. Some requirements:
Below is a table of some open tasks that people may wish to consider working on and links for more information.
* It must run on at least Linux, Windows XP, Mac OS X -- more are preferable, of course. You could use wx.
These tasks can be considered in addition or in conjunction with anything on our [[TODO]], any other task or your own 'Anything you can dream of' project.
* Should likely be written in C++ (other languages, like Python or Java, might be acceptable, if the result is sufficiently portable.
* Browse at least the data of SCUMM v5 till v8 games.
* Support for older SCUMM versions, and HE SCUMM games, as well for non-SCUMM games, is not necessary, but the code should be written modular/abstract enough to make it possible to add support for more data formats w/o too much trouble
* Only viewing data is necessary, not being able to edit it (although we won't complain if that's possible :)
* The interface can be designed in many different ways, but at least SCUMM data tends to suggest a main view with some kind of "data tree", in which one can select specific resources, and view them.
* Viewing the raw hex data of resources is required.
* It should be possible to add custom "views" for data (e.g. viewing images as images, not just as hex data; or hooking up a script disassembler; etc.). It is *not* necessary to provide such viewers for all resources types initially, but it must be possible to add them.


== Tools ==
They are usually NOT kept up to date. Please contact us (ideally via IRC) before you even start thinking about one of these tasks. Again, see [[GSoC Ideas]] if you're looking for Google Summer of Code ideas for 2014.


=== Tools: Rewrite descumm ===
<!--The GSoC workload figure was used to indicate the percentage of GSoC project time we consider this task will take an average competent programmer. These are just rough guides and should you feel you can undertake a task well in less time (or take longer but deliver a much better or more feature rich result) please feel free to mention this on your application and select your tasks accordingly.-->
<font color="magenta">TODO</font>


...to do proper recompilation (inspired by jode 
and other Java decompilers), so that it can properly decompile 
constructs like switch, do{}while() loops, etc. (I have lots of notes 
on this :)


=== Tools: Overhaul the compression tools ===
<dpl>
We offer a multitude of command line tools in a separate packages (scummvm-tools).
category = Open Tasks
The majority of these tools are used to (re)compress audio data. This greatly helps users who want to play their games on devices with limited storage, like PDAs and smart phones.
include = {Infobox_OpenTasks} Inforow
table = class="wikitable sortable" ,-, Task, (Outdated) Workload, Technical Contact(s), Subsystem
</dpl>


The user can choose between MP3, Ogg Vorbis and (in those cases where it makes sense) FLAC compression. The tools take the original data files, extract sound data, compress them, and reassemble everything into new (smaller) data files.
== Current TODO Lists ==


There are various ways in which these tools could be improved:
Below is a table of all the TODO lists currently on the wiki. These less detailed tasks can be considered in conjunction with anything from our larger open task list or your own 'Anything you can dream of' project.
* Write a portable GUI for them -- that's a big task and hence has it's own section (see below)
* Unify their command line interfaces
* Unify the actual compression code -- some partial work on this exists, but with a crude ad-hoc API, which makes it very difficult to use them and also inefficient
* Right now, compression works by invoking external encoder binaries (oggenc, lame, flac). To this end we write data into a temporary file, invoke the external encoder, and read back the file it created. It would be nice if one could instead link against suitable encoder libraries, and provide compression binaries which are fully self-contained. Also this would make it possible to perform in-memory compression (which could provide a noticable speedup).


=== Tools: Write a portable GUI for the tools ===
A TODO list by its very nature if often made up of vague pointers or ''one line'' ideas. Please seek clarification if you are unsure of any [[TODO]].
We offer a multitude of command line tools in a separate packages (scummvm-tools). Several of these tools are to be used by end users, mainly to (re)compress their data files (good for systems which have not that much storage, like cell phones).


Now, asking end users to use command line tools to perform common tasks is not quite unproblematic. We would like to make it easier for users to compress their data files, by offering them a nice graphical user interface (GUI). It  should support at least Linux, Windows, Mac OS X, ideally more. This could for example be achieved by using [http://wxwidgets.org wxWidgets] or [http://www.trolltech.com/products/qt/ Qt].


Note that the command line versions of the tools should still be available, for use in shell scripts or on systems where the GUI is not available. This likely requires modularizing the code sufficiently.
<dpl>
 
category = TODO List
Also note that this task meshes well with the previous task (of overhauling the compression tools).
include = {Infobox_TODO} Inforow
 
table = class="wikitable sortable" ,-, Task, Technical Contact(s), Subsystem
== Residual ==
</dpl>
''Technical Contact'': [[User:Aquadran|Pawel Kolodziejski]]
 
=== Light-weight software renderer ===
Residual currently offers two different renderers: OpenGL and TinyGL. Neither offers an ideal solution. Not all OpenGL drivers accelerate the operations needed by Grim Fandango, and the TinyGL renderer, apart from being somewhat glitchy, doesn't run well on low-end hardware. It would be nice to have a more light-weight cross-platform renderer. Since Grim Fandango uses mostly static backgrounds, we could probably gain a lot just from more intelligent screen redrawing.
 
This shouldn't require any deeper knowledge of the game engine. The renderer appears to be fairly well separated from the rest of the engine already.
 
== Port specific projects ==
<font color="magenta">Porters, add your ideas here -- and soon, ''before'' we submit the project fo review!</font>
 
== Objectify CinE engine ==
''Technical Contact'': [[User:Sev|Eugene Sandulenko]], [[User:Aquadran|Pawel Kolodziejski]]
 
The cinE engine started out as an external project started by [[User:Yazoo|Yaz0r]]. Originally it was written in plain C.
ScummVM is a C++ project, so we need to objectify this engine without changing/breaking its behavior.
 
The engine itself is well-structured, hence many functions / variables which might be good candidates for being grouped together into a C++ class are already grouped by files.
 
No deep knowledge of the engine internals is required, but in any case the Engine is not that big, and thus
it should be possible to learn enough about it to start working in a relatively short amount of time.
 
We have previously "objectified" several other engines, namely SAGA, Gob and AGI, so one can learn a lot about various approaches how to do this by tracing through our SVN repository.
 
== Add 16bit graphics support to SCUMM engine ==
''Technical Contact'': [[User:Kirben|Travis Howell]], [[User:Sev|Eugene Sandulenko]]
 
SCUMM engine starting v5 originally was developed for 8bit graphics. At version 6 it got forked by Humongous Entertainment which extended it significantly. Later games even started to use 16bits graphics for backgrounds graphics and actors. See [[Humongous Entertainment/Progress/16bits Support|here]] for more detailed information.
 
This task requires good knowledge of C++, as we need a solution which will not clobber our code,
which will have minimal impact on 8bit games, and can be optionally turned off at compilation stage.
 
If you don't have any of the required games, there are several [http://www.scummvm.org/demos.php demos] available.
 
== Implement "return to launcher" feature ==
''Technical Contact'': [[User:Fingolfin|Max Horn]]
 
Presently we have to exit ScummVM application completely when users exits a game because most
engines do not clean up memory properly on their exit.
 
What we need is to analyze what's going on there and plug all memory leaks, properly shut down
subsystems like sound, so it will be possible to play more than a single game within one
session.
 
The task will require good use of memory leak analyzer and C++.
 
== Mixer improvements ==
''Technical Contact'': [[User:Fingolfin|Max Horn]]
 
<font color="magenta">TODO</font>
 
* High quality resampling
* reduced latency (e.g. by using double buffering) to avoid stutter issues
 
== Add support for TFMX, and more Amiga MOD formats ==
''Technical Contact'': [[User:Sev|Eugene Sandulenko]], [[User:DrMcCoy|Sven Hesse]]
 
Since we're adding (and have added so far) support for different Amiga game versions, we need support for the sound files too.
Currently we need support for following formats:
 
* TFMX a (non-MOD) format used by Monkey Island 1. There is a [http://freshmeat.net/projects/tfmx-play/ player] for it already, which is written in rather poor C, also it misses marco implementation. [http://www.wotsit.org/download.asp?f=tfmx This] documentation may be useful, it isn't complete though. If you don't have the Amiga version of Monkey Island 1 you can use the [http://quick.mixnmojo.com/demos/mi1amigademo.zip demo] of Monkey Island 1.
 
* MaxTrax support for Kyrandia 1. The Amiga version isn't supported yet, but [[User:LordHoto|LordHoto]] will be working on it when his copy arrives. A Motorola 68000 (short: 68k) assembler implementation by Joe Pearce can be found [http://amiga.emucamp.com/wt/files/sources/SRC_MaxTrax.lzx here]. It would be necessary to reimplement it in proper C++, naturally a must for this task is 68k assembler knowledge. If you don't have the Amiga version of the Legend of Kyrandia, there are [http://www.exotica.org.uk/tunes/unexotica/games/Legend_of_Kyrandia.html sample modules] available.
 
* SoundFX is used by the Future Wars and Operation Stealth games of the cinE engine. The player is already implemented, but it cannot load music stored in Amiga format with combined track info and instrument info. The existing code only supports loading them separately, which happens to be the way they are stored in the DOS version. If you don't have the Amiga versions of the required games, you can use the [http://quick.mixnmojo.com/demos/fw_demo_ami.zip demo] of Future Wars and the [http://quick.mixnmojo.com/demos/op_demo_ami.zip demo] of Operation Stealth.
 
== Rewrite FMOPL emulator ==
''Technical Contact'': [[User:Sev|Eugene Sandulenko]]
 
Many games supported by ScummVM contain sound data intended for the [http://en.wikipedia.org/wiki/AdLib AdLib] Music Synthesizer Card, or other AdLib-compatible hardware like the SoundBlaster. These sound cards used the Yamaha YM3812 sound chip (also known as OPL2) to produce sound via FM synthesis. For more information about how this is done, see Jeffrey S. Lee's web page on [http://www.shipbrook.com/jeff/sb.html Programming the AdLib/Sound Blaster FM Music Chips].
 
In ScummVM we use the well-known FMOPL emulator from MAME V0.37a with some modifications (the name is the composition of "FM" and "OPL", see above). That was one of the few
versions on MAME released under the GPL, making it legal for us to use this particular version of the FMOPL code. Jarek Burczynski later rewrote the FMOPL emulator to be bit-precise, but unfortunately for us his work has only been released under a GPL-incompatible license.
 
What needs to be done is to understand Jarek's current code and write a new emulator. Efforts must be made to avoid verbatim copying of his code, to ensure no license violation takes place.
 
There are several approaches to do this, but most are not suitable for a single developer. A possible approach would be to fix our current FMOPL code by looking at how Jarek's code works. Another would be to start with a second, totally different emulator which we have and gradually improve that one (which was written by Ken Silverman and released under the GPL).
 
<font color="magenta">Fingolfin has some doubts whether this is a realistic project. In particular, the approaches suggested above would possibly still violate Jarek's license, as most license do cover "derived" work -- and looking at some code and then writing your own definitely falls into that category</font>
 
== MIDI enhancements ==
Many of the adventures supported by ScummVM make use of MIDI music. Which is why we already include several devide drivers for varios MIDI APIs and emulators (e.g. ALSA, Windows MIDI, Mac OS X CoreAudio/CoreMIDI, fluidsynth...).
 
=== MIDI device configuration ===
Right now, the MIDI drivers are treated by ScummVM in a rather single minded fashion: Either a driver is linked in and hence "available", or not. It's not possible to configure anything about them (like ports to be used etc.), nor does it ever take into account that a single driver might correspond to multiple devices (after all, you can plug several sequenecers into your MIDI port; or you could have configured several different sound font settings in your MIDI emulator). Hence, this needs to be enhanced:
* An API is needed to query the OSystem backend for a list of available MIDI *devices*, not drivers
* These devices should be configurable via the GUI; this needs to be done in a flexible (different devices/drivers offer different settings) and portable fashion.
 
=== XMIDI parser ===
Several of our games make use of the XMIDI format. We already have a parser for it (see sound/midiparser_xmidi.cpp), which was based on code from the [http://exult.sf.net Exult] project, but it is incomplete. Specifically we require support for XMIDI_CONTROLLER_FOR_LOOP and XMIDI_CONTROLLER_NEXT_BREAK, the XMIDI code (see audio/midi_drivers/XMidiSequence.cpp) from the [http://exult.sf.net Exult] project, could be used as reference again.
 
 
 
== Many tasks with AGI engine ==
''Technical Contact'': [[User:Sev|Eugene Sandulenko]], [[User:Stu|Stuart George]]
 
Several tasks in [[AGI]] engine do not require to own original [[Sierra]] games. Generally,
Sierra games work better than [[AGI/Fan Games|fan made]] ones.
 
* Implement AGIPAL, AGI256 and AGI256-2 engine extensions
* Fix bugs triggered by fan made games
* Finish implementation of Apple IIgs sound
* Finish implementation of predictive input
* Amiga style (colored) menus
* Hercules mode
 
Some of above mentioned tasks will require engine knowledge, but the engine itself is tiny and well documented, so it should be doable. Additionally NAGI and DAGII could be used as a reference. Particularly, NAGI is known to be more compatible with fan made games

Latest revision as of 18:40, 29 May 2016

See GSoC Ideas if you're looking for Google Summer of Code ideas for 2014.

See Closed Tasks for a list of tasks proposed the previous years


Current Open Tasks

Below is a table of some open tasks that people may wish to consider working on and links for more information. These tasks can be considered in addition or in conjunction with anything on our TODO, any other task or your own 'Anything you can dream of' project.

They are usually NOT kept up to date. Please contact us (ideally via IRC) before you even start thinking about one of these tasks. Again, see GSoC Ideas if you're looking for Google Summer of Code ideas for 2014.


<dpl> category = Open Tasks include = {Infobox_OpenTasks} Inforow table = class="wikitable sortable" ,-, Task, (Outdated) Workload, Technical Contact(s), Subsystem </dpl>

Current TODO Lists

Below is a table of all the TODO lists currently on the wiki. These less detailed tasks can be considered in conjunction with anything from our larger open task list or your own 'Anything you can dream of' project.

A TODO list by its very nature if often made up of vague pointers or one line ideas. Please seek clarification if you are unsure of any TODO.


<dpl> category = TODO List include = {Infobox_TODO} Inforow table = class="wikitable sortable" ,-, Task, Technical Contact(s), Subsystem </dpl>

Retrieved from "https://wiki.scummvm.org/index.php?title=OpenTasks&oldid=22799"