Embedded Development on the Qt

By: Robert McMillan
Thursday, February 13, 2003 09:03:29 AM EST
URL: http://www.linuxplanet.com/linuxplanet/interviews/4673/1/

An Interview with Trolltech CEO Haavard Nord

If you were at LinuxWorld Conference & Expo in New York last month, you may have caught IBM's demo of its PowerPC 405LP-based PDA reference design. Though IBM has deigned Linux-based routers and set-top controllers, the 405LP design was IBM's first Linux-based PDA.

On February 12, Norway's Trolltech AS formally announced its relationship with IBM, which is using Trolltech's ATopia office application suite as part of its 405LP design. LinuxPlanet caught up with the nine-year-old company's CEO Haavard Nord to ask him about the IBM deal, the latest on Trolltech's Qt libraries, the embedded device market, and about what Sun could learn from Trolltech's dual-licensing scheme.

LinuxPlanet: What is Trolltech's relationship with IBM?

Havaard Nord: We have for a long time been working closely with IBM. We have both seen the need for coming up with a well-defined platform for embedded Linux devices. With this announcement, we formalized the cooperation with IBM. The device demonstrated at Linuxworld was the first reference device using a combination of IBM software and TrollTech software.

LP: So right now, the deal you have is only for this one reference platform?

Nord: It is the start of a long-term relationship between TrollTech and IBM.

LP: Did you have any relationship with IBM before this?

Nord: We had actually worked previously with IBM. We helped IBM port ViaVoice, and create a voice-enabled interface to the KDE desktop almost two years ago.

LP: Is IBM contributing any technology to Qt?

Nord: IBM isn't contributing to the Qt codebase, but they are adding technology on the platform, but I do not think IBM is really ready to speak about this before they make a press release about this. But they are definitely adding technology.

LP: Does this mean that any reference platform coming out of IBM that involves a GUI will now include Qtopia?

Nord: Qtopia will be part of any Linux-based platform IBM creates. Qtopia has also been chosen as the standard for Sharp's line of PDAs.

LP: But do you think that Qtopia and Qt/Embedded will have applications beyond the PDA?

Nord: I think applications are one of the very strong points of Qtopia. When Sharp released Qtopia on the PDA, there were no more than 600 applications. I met Sharp a few days ago in Japan, and their community person said they were closer to 1,000 applications, including commercial software. Some of these applications are types of instant messaging applications, some are games; we have also seen that applications have been developed for a coming smart phone. We're seeing a trend that embedded Linux and Qtopia are moving into the phone space.

With the GPL and commercial licensing of Qtopia, it's attractive to both the open source community, and also to companies.

LP: IBM is also a big supporter of Java, but I'm unsure how that plays into their embedded products. Is Qt/Embedded basically the alternative to Java?

Nord: That's a very good question. Actually, Qt and Java are not competitors. They are very complimentary. For instance on the Sharp PDA, you have both Qt and Java running side-by-side in seamless integration where Java applications have the native look and feel, so they look exactly like Qt applications.

Qt is used to write all the types of applications that you would use Java to write. When it comes to email clients, instant messaging clients, and any application that requires a sophisticated user interface, Qt is the right choice for that. When it comes to the enterprise applications and also some downloadable applets, Java is the best choice for that.

When we came up with Qt/Embedded, we saw the need for integrating Java with the platform, and we created a layer called QtAWT, which made it possible to integrate Java seamlessly together with QT Embedded.

LP: I assume that this is related to the AWT libraries

Nord: The way it works is, if a Java application makes an AWT call, it is interpreted by QtAWT and instead of the Xlib, it is sent to Qt.

LP: What if it's a Swing call?

Nord: Swing is a rather large and slow library on top of Java, and I have not seen any use of Swing in embedded products at all. You need at least a one gigahertz CPU to run Swing applications. Swing is more or less abandoned as a GUI layer for Java. There has been much criticism of Swing. We think that Swing is actually very little used, even on the desktop.

LP: There's something I've always wanted to ask you about Java. A lot of people have suggested that an open source license for Java would strengthen the platform, but it's always seemed to me that Sun could learn something from TrollTech and adopt the kind of dual-track licensing that you have with the Qt libraries. Do you think that that would be an appropriate approach for Java.

Nord: I think it could perhaps be that. That is, of course, up to Sun.

LP: So are there reasons why this dual approach to licensing would not work for Java?

Nord: You know, in terms of licensing, Qt and Java are fairly comparable, and applying dual license for Java, in my view, would probably make sense. We have had a dual licensing scheme for five or six years now. It has been extremely good for the company. Over the last four years we have actually doubled sales every year -- also in the recent downturn. The dual licensing really works. It gives the open source community the best tool available, and it gives the commercial developers a tool that is widely used -- it is very easy to recruit Qt developers. The tool is very robust, and there are so many developers using it.

Qt and the GPL

LP: Within your dual licensing scheme, you guys switched to the GPL about three years ago, right?

Nord: I think it was about two and a half years ago.

LP: It seems that before you adopted the GPL, you had some of the same concerns as Sun.

Nord: What we were concerned about was if we did a GPL version of Qt, that someone would take this GPL version and make an alternative incompatible version of Qt.

LP: Which is Sun's concern with Java. So how has the GPL worked out for you?

Nord: Our experience with the GPL has been simply tremendous. We have not seen any such thing as a fork. The open source community has been extremely supportive of our GPL licensing. We get lots of good bug reports; we get contributions; sometimes major contributions such as Unicode support, from one developer. But I've never seen any attempt to do any fork.

LP: Why is that?

Nord: First of all, because we have such a staff of engineers developing Qt, that if there's a need to implement new features in Qt, we do it. If we had stopped developing Qt, then there would have certainly been a fork. But this is a good thing for the community, because if we were to stop developing the product, there is an insurance that somebody else could take over.

LP: With additions like the recent SQL module, it seems like Qt is becoming more than a GUI toolkit. Where do you see Qt going over the next five years.

Nord: We have a number of customers who have already said that they don't think of Qt as a GUI toolkit; they think of it as a development framework. One developer named Rainer Goebel in Holland has built an application called <a href=" http://www.brainvoyager.de/">Brain Voyager</a> for displaying real time MRI data. It takes a lot more than just a library of widgets to build that software, and so the fact that there are file access classes, networking classes, database APIs that are platform independent, these are things that are clearly moving Qt out of what was a very useful niche, and into something that's even bigger.

LP: So what would be Qt 4.0 features?

Nord: First, we are not trying to bloat Qt with features. What we first try to do is see if there are parts within Qt we can rewrite to make it smaller and even more efficient. We think that this may be our most important job. Secondly, we're looking at what are the trends in the software development industry. Over the next few years we will continue adding functionality to Qt, but we will do it in loadable modules.

LP: Right, but do you have any examples of the kind of loadable modules you'd like to have in 4.0.

Nord: I don't really have that, no.

LP: There were Qtopia-enabled PDAs based on the AMD and PowerPC processors at LinuxWorld Expo this year. What about Intel? Are you doing anything with them?

Nord: We're also working closely with Intel. One thing that is a tremendous benefit of embedded Linux is that it's very easy to target your reference platform to different types of hardware, when it comes to CPUs or types of display or input devices.

LP: So Intel has a reference platform that includes Qt Embedded and Qtopia right now?

Nord: I'm not sure of the status of this, so I'm not sure I can comment right now.

LP: So you're working with Intel, but there's nothing that's been announced?

Nord: I wouldn't say so.

LP: What about the port of Mozilla to the Qt Toolkit, QT Scope? What's happening with that? Is Trolltech committing any resources to this?

Nord: I was actually one of the seven people on the initial team creating that port. The reason we did that was to demonstrate the capabilities of the Qt toolkit, and also to give the community some code.

LP: So are you maintaining it now?

Nord: No we are not involved in that.

LP: Why not?

Nord: Because our job is really to focus on the framework, and also to focus on Qtopia. We think that Qtopia together with the IBM reference platform is very important for the embedded or consumer device industry. That's really our focus.

Nord: The phone is probably the most important area, but you will also see it in cars, in home appliances -- you know, kitchen devices -- you will continue to see it in PDAs. But the phone is probably the largest area where embedded Linux and Qt will make an impact.

I expect that you'll see some use from Japan. The industry in Japan is in transition. Previously they had been working with a proprietary operating system from µITRON, but going forward, their devices need more sophisticated functionality. They need to Web browse, they need Internet connectivity, and µITRONis not really up to delivering that. And this is where embedded Linux will play a major role. Not only in Japan. We are also seeing the same trend in China and India, and Europe -- basically a who's who in the consumer electronics industry.