February 2014

WireOver - Fast, Free, Secure File Sending

WireOver is a Mac, Windows and Linux application for sending and receiving files. It's easy to use and very low friction, requiring only entry of an email address and click on a received web link to set up. Receiving an unsolicited send is even easier, as acting on the receipt of the notifying email naturally associates that email with the recipient.

Transfers (by subscribers) use perfect forward secrecy, and can be entirely asynchronous, so sender and receiver need never be online at the same time. Of course if they are, then transmission goes as fast as the physical network allows.

We built the backend and client mainly in Python, supporting Mac and Windows back to 10.5 and XP respectively. For Linux we support 32 and 64 bit Ubuntu 12 and later.

Much of my focus has been on keeping OS variations from impacting the main body of the code. To that end, we're using wxWidgets to abstract the GUI, and I've implemented such native code as needed to interface with unwrapped aspects of the OS and third-party libraries. In some cases the fluent Python bindings to OS facilities just aren't fast enough, and native code is used there also.

June 2013

Glass Ceiling

Glass Ceiling is the ultimate female revenge fantasy. In Glass Ceiling, our hero Moxie fights her way up the corporate ladder—literally. By battling fresh men, backstabbing co-workers, asinine accountants, bad bosses and other office stereotypes.

Graphic and game design by Wendy Carmical, project management and game design by Maura Sparks.

It's written in C++ using OpenGL, and thus is completely portable between iOS, Android and OSX.

March 2012

SPARKvue Augmented Reality

Working with Sally Ride Science and PASCO I extended the desktop version of SPARKvue to support augmented reality views of the experimental setup.

In this enhanced version of SPARKvue sensors are tagged with fiduciary markers. The video from a camera pointed at the experimental setup is shown beneath normal UI elements, and measurements from sensors are drawn into the video as it runs.

November 2011

MOTOACTV HTTP Proxy

The MOTOACTV communicates with servers to share and manage its user's fitness information. The device is very small and interacting with a complex network configuration UI is not viable. So, when tethered, it communicates through an HTTP proxy I wrote that runs on the user's desktop machine.

This is not my first full HTTP proxy; that was the desktop component of iMobimac Modem. In this case there were a couple of requirements that made things interesting.

Generally a proxy is a long-running system service, and it builds and evolves knowledge of what outbound paths and upstream proxies are available and usable. This proxy launches when the device connects, and shuts down when it quits, so any knowledge it can acquire is likely to be stale.

The approach I took was to try everything at once -- initiate connections on every combination of network interface, proxy name and resolved IP address, and use whichever wins the race. Thereafter it starts with the last thing that worked, and only scatterguns after a timeout. Interestingly this makes regular desktop browsing more responsive too, but it's pretty abusive to the network infrastructure and is only safe for idempotent GETs.

The other interesting feature was handling Proxy Auto Config (PAC) files. These are chunks of javascript that take a desired host name and return the name/address of the proxy that should handle the request. I'd never come across one in the wild, but they're very common in corporate networks where there's free rein inside the firewall, but all external access is via proxies. The system facilities on OS X are sufficient that the task can be handled by calling CFNetworkExecuteProxyAutoConfigurationURL. Windows on the other hand can almost do the job. The WinHTTP library can handle a PAC specified with a network URL, but not with a local file. So when we see that the PAC is a local file we fabricate an HTTP URL referencing a port we're handling, and any request on that port returns the content of the PAC file.

March 2009

ZooLib BBDaemon

The ZooLib BBDaemon lets multiple Mac applications talk to USB-connected BlackBerrys concurrently. Obviously this is something that Research in Motion could make possible, but as they haven't we're posting a pre-built installer that takes the pain out of getting things working.

If you're using Missing Sync for BlackBerry 2.0.1 and iMobimac Modem then this is what you need.

BBDaemon runs as a user-space process, not a kernel extension. The installer simply puts the executable in /Library/PrivilegedHelperTools and a launchd control file in /Library/LaunchDaemons.

RIM's own Mac applications (PocketMac for BlackBerry and BlackBerry Media Sync) take a different approach. They each install a kernel extension which grabs any USB-connected BlackBerry, and prevent any other application (including each other) from being able to talk to it.

The installer we've posted was built with revision 533 of ZooLib. You can check out the source and build it yourself:

svn export -r 533 https://zoolib.svn.sourceforge.net/svnroot/zoolib/trunk/zoolib

svn export -r 533 https://zoolib.svn.sourceforge.net/svnroot/zoolib/trunk/zoolib_samples

cd zoolib_samples/BlackBerry/BBDaemon/osxpackage

sh build.sh

The executable and launchd file must be owned by root/wheel, so the build.sh script uses sudo to change the ownership – thus you must be logged in with an administrator account and you may be prompted to enter your password.

February 2009

The Missing Sync for BlackBerry

Mark/Space has released The Missing Sync for BlackBerry 2.0. This latest version provides a rich suite of synchronization options, made possible by a device-side Java application developed by Electric Magic. The Mac application uses our ZBlackBerry Mac/Black SDK for its USB communications.

December 2008

Zorap, Web-Based Video Chat

Zorap web pages are multi-party multimedia environments. Video from your webcam and audio from your microphone, photos, music and video from your own computer are shared to tens of your friends via a Zorap Server. Web content, including YouTube and other video sites are similarly shared, all in an exciting and customizable drag-and-drop interface.

Electric Magic implemented the Mac-specific portions of the Zorap web plugin, supporting Safari, Firefox and other modern web browsers.

September 2008

SiteGrinder Photoshop Plugin

If you’re a Photoshop virtuoso, MediaLab’s SiteGrinder carries those skills over to the creation of exciting web pages. The SiteGrinder Photoshop plugin takes your document’s layers and attributes, crunches through them and generates HTML, CSS and optimized web graphics ready for the public.

SiteGrinder’s UI is beautifully implemented in Flash, and Electric Magic helped MediaLab get that UI working in older and newer versions of PhotoShop.

July 2008

OS X Accessibility from Java

Our client’s application is a scriptable form-filling engine, used by their customers to automate computer-based form submission. Their engine is written in Java, and uses the Abbot GUI testing framework to drive third-party UIs. For Mac OS X support we implemented a JNI shim that made the AX API usable from Java.

March 2008

Mac/BlackBerry SDK

The BlackBerry is a very popular mobile communications device. Official Mac support from Research in Motion is limited to providing the PocketMac utility as a free download. With no official SDK the Mac/BlackBerry ecosystem has seen very little activity.

ZBlackBerry is a suite of code that implements the BlackBerry USB communications protocol in a generic fashion. A few hundred lines of code let Macs use that protocol. A few hundred more allow multiple Mac applications to talk to a single BlackBerry simultaneously, something that has not been possible till now.

ZBlackBerry can also make a BlackBerry connected to a PC accessible via the same API as is used when it's connected directly to a Mac. This lets Mac application developers run their BlackBerry application under the Windows-based debugger and still have it communicate with their Mac application. This is a crucial capability when writing anything more than the most trivial application.

ZBlackBerry is part of ZooLib, our open source C++ library.

January 2008

iMobimac Modem

The Research In Motion BlackBerry is famous for its connectivity. iMobimac Modem runs on a BlackBerry and the Mac to which it is connected, and lets Mac applications access the Internet using the BlackBerry's connection.

The BlackBerry application is written in Java. It maintains a single communications channel with the Mac application, over which it receives requests to make, use and break network connections. The channel is multiplexed with ZooLib's Java ZStreamMUX on the BlackBerry side, and its C++ ZStreamMUX on the Mac.

Much of the Mac application's functionality is a C++ HTTP and port-forwarding proxy server, most of which is in ZHTTP. Its UI is implemented in Objective C using Cocoa Bindings.

The remainder of the Mac implementation effort was in reverse-engineering the BlackBerry/Host USB communications protocol.

May 2006

Knowledge Forum 4.6

Knowledge Forum 4.6's minor version number change belies just how different from its predecessor it really is.

Under the hood KF 4.6 has moved from using ZDBase for its backing store, instead using a tuplebase. This makes it possible to split HTML page generation into separate processes, potentially running on multiple front end machines. It also restores support for a rich client application, now written in Java, using ZTSoup to efficiently communicate changes in the tuplebase, whether made by other clients or by the web interface.

May 2004

Java Tuplebase Access

Initially I provided Java access to a tuplebase instance by implementing Java classes whose most interesting methods were marked as native, and thus invoked via JNI. This was very powerful because Java could use any tuplebase implementation simply by calling the appropriate factory function and I could expose any existing C++ functionality simply by implementing the appropriate JNI glue.

But native code can't be included with unsigned applets, so I ported ZTBRep_Client from C++ to Java. ZTBRep_Client is the most useful tuplebase implementation in that it talks to a ZTBServer instance on the end of a comms link, generally a network socket. It's also fairly large, and the async nature of the protocol makes things somewhat tricky. The normal Java synchronization model is based around monitors, which are not directly useful for implementing certain types of concurrent processing, so I implemented condition vars and mutexes to provide more appropriate tools.

August 2003

Knowledge Forum 4.5

Knowledge Forum 4.5 was a significant refinement of Knowledge Forum 4.0, with a much richer web interface, although still constrained by the need to support Netscape 4.x-era web browsers.

New features included support for upload and download of files as attachments to views and notes, headings within views, full text and attribute-based searches, and notification by email. It also supported graphs of useful metrics, implemented across platforms using ZDC_ZooLib.

On the back end, a significant change was moving from the original blockstore implementation to one based on B+Trees that uses a neat upward propagting copy-on-write of nodes to make it virtually bullet-proof - only a physical failure of the backing store can cause data loss.

November 2002

Web Browser Plugins

ZooLib's UI code requires only that there be a ZFakeWindow-derivative at the top of the enclosure hierarchy. In the distant past ZooLib included implementations of ZFakeWindow for Mac control panel cdevs, HyperCard XCMD windows, MacroMind Director XObject windows, Zoom closures, MacApp views and of course still does for ZOSWindows.

It was thus relatively straightforward to implement ZFakeWindow_NSPlugin, which translates between the Netscape browser plugin and the ZFakeWindow APIs. What was actually more difficult was finding a decent implementation of the plugin glue code and header files. In 2002 there wasn't anything that would work with current compilers and with current browsers, so most of the effort was in putting together ZNSPlugin, which is a usable implementation of the glue.

September 2002

Knowledge Forum 4.0

Knowledge Forum 4.0 took the radical direction of being web-only. We'd had some support for web access by virtue of a perl program that used the client's communications protocol to talk directly to the server, but perl wasn't pre-installed on Mac OS (Classic) or Windows, and it had some performance problems. So we ported the perl software to C++ and incorporated it into the server directly.

For a time we had native client and web access running simultaneously, but never in a released version. The 3.x client remains buildable as of May 2006, but still talks only to a 3.x server.

April 2002

Files

Most of my work till this point had not required 'interesting' operations with file systems, being restricted to creating and opening files in externally determined locations, then reading and writing the files' contents. When it became necessary to ennumerate the contents of directories, and to deal with permissions and locking I took the opportunity to define an API that would be consistent across Windows, Mac and UNIX whilst cleanly accomodating their differences.

The ZooLib file API doesn't address more esoteric file systems like VMS or IBM's MVS. It models a hierarchical system, with accomodations for special roots (like Windows' UNC paths and Mac Classic's multiple volumes with the same name). Files are byte-oriented, and as with other stream operations ZooLib's file Open and Create return a ref counted streamer object, and optionally an error enum providing more detail in the case of failure. The representation of a pointer to a node in a file system also follows ZooLib's practice of a using a smart object with value semantics.

The ZFile suite was the first place I formalized the notion of a 'trail'. This was another case where it was important to come up with a new name that was suggestive of an existing notion, but distinct enough from it that its different semantics could be defined. Picture a tree; a trail is simply the list of steps to be taken to navigate from some node to some other node. A step is either to traverse the link from the node to its parent, or to traverse the link from the node to one of its children. We represent a step as a string. An empty string indicates a 'bounce', a traversal to the parent of the node. Any other string indicates a traversal to the node with that name. Whether the name is attached to the child node, or attached to the link to the child node doesn't matter in this model.

The notion of a trail through a tree shows up in assets and in the handling of HTTP requests. Theoretically it could also be applied to tuples but I'm not quite ready to harmonize everything to that extent.

January 2000

Knowledge Forum 3.0

Knowledge Forum 3.0 took advantage of major enhancements in ZooLib that let the client be released for Windows as well as Mac OS. Much of Knowledge Forum 2.0 had been built around the Mac-only Zoom framework, and so had to be reimplemented. The parts of Knowledge Forum 2.0 built with ZooLib were simply carried forward, with refinements and enhancements.

By this time ZooLib abstracted Mac OS, Windows and UNIX, so the server could be hosted on all three OSes.
The text editing in Knowledge Forum 3.0's note windows used the PAIGE text engine, which was a fairly crusty 60,000 lines by this time, but was portable across Mac and Windows. So although the rest of the client could be built for UNIX, without the text editor it wasn't particularly useful and we never released a UNIX client, although that wasn't a big deal in 2000.
Unfortunately we also had to abandon Kevin Parichan's excellent painting implementation, as it was also Mac-specific. Instead we used ZooLib's NPainter, which used only ZooLib features and was thus completely portable.

January 1998

ZFiber: Threads At Interrupt Time

Fibers, at least in this context, are threads implemented using setjmp/longjmp to transfer control in a manner reminiscent of co-routines. They are a generalization of the stack-swapping used by NetPhone to run in the constrained environment it experienced when its deferred tasks were scheduled when an application with a tiny stack was current (yes Print Monitor, I'm talking about you).

Whereas NetPhone allocated some space for a stack to be used when invoking a stack-hungry function (the GSM codec generally), ZFiber calls setjmp to record the current stack and registers, then calls longjmp on the setjmp buffer previously initialized by the next fiber to be executed. Because we have complete control over the entire process this makes it very easy to turn async callback-based functions (like most of the Mac's IO subsystem) into blocking function calls. And the whole thing can run at deferred task time, simply by having the callback for an async function schedule a deferred task which calls longjmp to the first fiber that's marked as being both runnable and safe to be run at deferred task time. A fiber can change its deferred task time eligibility on the fly, so sections handling IO can be run at deferred task time, and thus not be subject to the latency imposed by having to wait till GetNextEvent, but sections that have to touch non interrupt-safe sections of the ToolBox can be run exclusively at normal time.

September 1997

ZOSWindow: Abstracting OS Window APIs

ZooLib had always maintained the ZFakeWindow abstract interface between user interface elements and the hosting environment. This allowed ZooLib UI widgets to be used within MacApp applications, standalone applications, Control Panels, XCMD windows and XObject windows. It worked very well.

However, when the portability axis was across platforms rather than hosting environments there was the potential for a lot of replication and ugly code in ZWindow, the standalone application derivative of ZFakeWindow.

So, I abstracted the interface to OS-windows, placing it in ZOSWindow, and modified ZWindow to use a ZOSWindow, rather than be conditionally compiled for different platforms.

August 1997

Knowledge Forum 2.0

Knowledge Forum 2.0 is a computer supported collaboration environment designed to foster the growth of knowledge building communities. It's based on the CSILE project, developed at the Ontario Institute for Studies in Education and is published by published by Learning in Motion.

CSILE was pioneering and innovative, but in May 1994 limitations in its feature set and a desire to see it in wider use led to a collaboration with Learning in Motion to redesign it. The scope of the necessary changes neccessitated a complete reimplementation and the decision was taken that it would be released as a commercial product.

Cyrus Ghalambor started work on the KF 2.0 client application in July 1995. I was busy with NetPhone till December 1995, when I started working full time on the client's data API and the server that would satisfy its requests. We looked at several existing database libraries, but they were either too limiting or could not run on Mac OS (Classic, of course). So I implemented ZDBase, a portable database engine that was built on ZooLib. Client and server communications and the server's administration UI were also built using ZooLib.

The client application's event loop, menus and windows were handled by a refinement of Berkeley Systems' Zoom framework. It had two main types of windows. The note window used Zoom for its controls, and the WASTE text engine for its text editing panel. The view window provided a two-dimensional icon-based representation of collections of content, its operation was closely modeled on that of Apple's Finder, and it was implemented using ZooLib. The note and view windows also contained pictures, in-line with the text in the note window and in a layer behind the icons in the view window. Pictures were edited in place using a nice painting implementation by Kevin Parichan.

Other dialogs and property inspectors were based on Zoom or ZooLib, depending on whether they were written by Cyrus or by me.

April 1996

DigiPhone

The publishers of Digiphone, a VOIP application for Windows, took a shortcut to getting Mac compatibility - they (indirectly) bought NetPhone from Electric Magic, and had me add support for DigiPhone's communications protocol and audio codec.

August 1995

QuickTime Conferencing Components

QuickTime Conferencing was a short-lived project that tried to bring live communications technologies under the umbrella of QuickTime. To make it usable for most people's net connections, it needed codecs that were both low bandwidth and required limited CPU power. That combination was tricky, and so Apple asked me to help them by packaging NetPhone's CVSD and modified GSM codecs as audio components that could be used by QuickTime.

January 1995

NetPhone

In 1994 the Internet was just starting to be available in people's homes and offices. NetPhone was the first application to support what's now known as VOIP (Voice Over IP) without requiring a high-speed connection.

January 1994

Measurement in Motion

Measurement in Motion is a pioneering math and science analysis and investigation tool. It lets students take measurements from real-world video footage, then tabulate, graph and derive secondary measurements from their data. Conversely, students can generate data algorithmically and superimpose it over video to provide visceral confirmation of hypothesized behavior.

June 1993

FinderHider

FinderHider was a neat hack prompted by Joe Sparks' lamentations over the occasionally unprofessional look of Macromind Director animations. At the time there were several different screen sizes in use, 512 x 384, 640 x 480, 832 x 624 and even (for the well-heeled) 1024 x 768. But the 'stage' (the playback area) of any particular Director title was always fixed in size, and the computer's desktop would be visible when using a title on a computer with a monitor larger than the stage.

FinderHider simply put a border round the stage that would dynamically size to fill the entire screen.

The code that did the work was a simple WDEF whose structure region was taken from the main screen's bounds and whose draw method filled in the extra space with a color or pattern. Director itself was completely oblivious to the change, it just saw a window with a very, very thick border. Most of the development work was actually in the installer application, which added the functionality to the standalone playback 'projector' with a simple drag-and-drop, and in the XObject that provided runtime control of the border.

I revised FinderHider a couple of times in response to customer requests, adding support for non-rectangular borders, transparency in the stage itself, and for use in HyperCard and Authorware titles.

November 1992

Marrakech

Marrakech took the hypermedia concepts I explored in WorkSpace and applied them to the problem of managing workflow and assets for multimedia development.

June 1992

Creative Whack Pack

The Creative Whack Pack was a software version of Roger von Oech's famous creativity-enhancing deck of cards. Scott Kim collaborated with Roger on the application's design, which had some neat features including a system-wide hot-key that would bring up a random card, a click on which would seamlessly invoke the application. The app's window also showed animated transitions between screens (dissolve, rotate etc).

June 1991

WorkSpace

WorkSpace was an interesting application that took user interface ideas from Andy Hertzfeld's Servant, and hypermedia ideas from all over, and combined them into a personal information manager that used the web of links between entities to represent meaning. It was never released as a product, but was where I first started creating ZooLib, and formed the basis of Marrakech and ultimately of Measurement in Motion.

June 1990

MediaMaker

MediaMaker was a ground-breaking application that provided a Finder-like interface to manage multimedia content, coupled with a timeline for assembling that content into a finished production. It controlled laserdisc players, VCRs and CD-ROM drives, managed video overlay cards, played AIFF files (no mp3s back then), MacroMind Director presentations and displayed PICT files (no JPEG either).

It was the commercialization of a project from the BBC's Interactive Television Unit called 'Future Worlds'. Future Worlds was investigating how to create video content that could be used in a traditional linear documentary and also in a hyper-linked computer-based environment. I worked at the BBC for all of three months before the ITU was spun off into an independent company, the MultiMedia Corporation. MediaMaker was published by MacroMind, and I went along with it to San Francisco.

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