Planet Qt

Qt Graphical Effects in Qt Labs

2012-02-02T09:56:46+00:00

Introduction

The Qt Graphical Effects project is on its way to offer a set of design neutral visual effects for Qt Quick 2.0.

Over twenty ready-made QML graphical effect elements are currently available. The effects include code for blending, masking, blurring, coloring, and much more. There are still areas to improve and extend — all ideas, feedback, proposals and even concrete contributions are welcome!

The Effects

Using the effects

Using the graphical effect elements should be straightforward for developers and technically oriented designers as you only need to know basic Qt Quick/QML to get started.

Any QML item can be used as a source item for an effect. You can add a drop shadow to an image, for instance, as follows:

import QtQuick 2.0
import QtGraphicalEffects 1.0

Item {
    width: 300
    height: 300

    Rectangle {
        id: background
        anchors.fill: parent
    }

    Image {
        id: butterfly
        source: "images/butterfly.png"
        sourceSize: Qt.size(parent.width, parent.height)
        smooth: true
        visible: false
    }

    DropShadow {
        anchors.fill: butterfly
        horizontalOffset: 3
        verticalOffset: 3
        radius: 8.0
        samples: 16
        color: "#80000000"
        source: butterfly
    }
}

Getting started

Get and build Qt5: http://developer.qt.nokia.com/wiki/Building_Qt_5_from_Git

Make sure that qtbase/bin is in your path and QTDIR points to /qtbase

Get and build Qt Graphical Effects module: https://qt.gitorious.org/qt-labs/qtgraphicaleffects

git clone git@gitorious.org:qt-labs/qtgraphicaleffects.git
cd qtgraphicaleffects
qmake
make install

To see the effects in action, run the code examples from the graphical effects doc/src/snippets folder:

qmlscene doc/src/snippets/DropShadow-example.qml

or launch the Testbed application:

qmlscene tests/manual/testbed/testBed.qml

The Testbed application is a convenient way to browse the effects and their properties as well as to visualise the results. Select an effect from the left, adjust its properties on the right, and see the result in the center in realtime:

API and documentation

The API for each effect is a set of QML properties. The effect properties can be animated just like any other QML properties. The documention contains property descriptions and basic usage examples. To generate the documentation, execute the following commands in the qtgraphicaleffects projects folder:

qmake
make docs

Open the generated doc/html/qml-graphicaleffects-index.html in a browser to view the documentation.

Implementation details

QML ShaderEffect is a built-in element in Qt Quick 2.0. This powerful QML element allows combining OpenGL Shading Language (GLSL) and QML, and makes it easy to implement visually impressive custom effects. Under the hood, all the effects in this project are based on ShaderEffect elements. Only QML and GLSL have been used, and there are no additional C++ APIs. If you are familiar with GLSL, you can easily study how the existing effects have been implemented. You can then create custom effects by modifying and combining the basic effects.

Links to related blog posts and specifications

Qt Commercial Support Weekly #12 - To delete or not to delete

2012-02-01T21:13:09+00:00

As a great literary developer may have once said, "To delete or not to delete, that is the question." As we know, with C++ we are expected to clean up after ourselves whenever we do something new so that the memory is available and does not cause ...

New Qt SDK features updated Qt Creator, Qt 4.8 for desktop and new Qt mobility APIs

2012-02-01T10:41:51+00:00

A new Qt SDK, the Qt SDK 1.2, is now available for download, and it makes it easier than ever to create rich applications with improved performance.

The new SDK includes the latest version of Qt Creator (2.4.1) as well as Qt 4.8 for desktop and embedded developers including Windows, Mac and Linux/X11 (released as stand-alone in December).

Qt mobile app downloads continue to grow in Nokia Store, and the SDK update contains mobile improvements for the Symbian and MeeGo Harmattan 1.2 targets, new Qt mobility examples in Qt Creator and easy integration of the Qt In-App Purchasing API, which enables developers to build in-app purchasing into their Qt mobile application.

Key benefits within the updated SDK include:

Qt Creator 2.4.1

Qt Creator 2.4.1 is a patch version containing some fixes and enhancements for Qt Creator 2.4.

- Improvements in the C++ and QML editors, such as syntax highlighting in QML, and improved static QML code-checking features.

- Improvements of the code refactoring tools

- Reusable “schemes” for the coding styles (C++ and QML) between projects

Qt 4.8 for desktop and embedded Windows, Mac and Linux/X11

- Qt Platform Abstraction, which makes it easier to port QtGui to new windowing systems

- Qt Quick improvements including the possibility to embed OpenGL shader effects in Qt Quick apps with the help of a QML shader add-on.

- Qt WebKit 2.2.1 with updated version of QtWebKit from the WebKit project, including a wide range of improvements to the HTML, CSS and JavaScript technologies.

- Threaded Open GL making it easier, and more thread safe, to render OpenGL from more than one thread concurrently

More Qt mobility code examples.

The updated Qt SDK includes over 20 Qt Mobility examples.

In-App Purchasing

In-App Purchasing enables developers to seamlessly offer additional, premium content for purchase, such as new items/levels/functionality and try and buy application upgrades, within the confines of the app experience.

This enables new revenue opportunities within mobile Qt apps. The In-App Purchasing API beta has been available and manually installable, but now this component can be added and maintained in the Qt SDK configuration, simply by using the SDK maintenance tool.

Having the opportunity to include In-App Purchasing can increase revenue substantially for mobile developers. With strong, continued growth of Qt app downloads in Nokia Store, and the store itself continuing to grow – over 11 million downloads per day – Qt continues to be a good choice for developers creating mobile apps for the 155+ million Qt enabled Nokia phones currently in the market.

Congratulations to the team who worked on this release. We all hope you enjoy the new Qt SDK 1.2

Get started and download here

Daniel Kihlberg

Global Director Qt Ecosystem

Qt SDK 1.2 Released

2012-02-01T10:35:02+00:00

We are happy to announce that a new important update for Qt SDK is published.
This Qt SDK 1.2 update sets a new baseline for the developers for a longer perspective. Some of the features have already been available as online updates, but Qt SDK 1.2 now integrates the very latest tools, most recent mobile build targets for Symbian and Nokia N9, and the still fresh Qt 4.8 for desktops. We have also introduced some improvements to the SDK and its maintenance tool.

As a summary, this is what is new in the Qt SDK:

Fixes for Qt Creator 2.4 in a new 2.4.1 patch update
Qt 4.8 for desktops delivering Qt Quick 1.1, Qt platform abstraction, Qt WebKit 2.2, and threaded OpenGL. See Sinan’s blog post for more details.
More Qt Mobility examples for Nokia N9 and Symbian devices
Ability to specify network proxy setting in the SDK Maintenance Tool
Update to the Symbian Complementary Package introducing Analyze Tool plugin and new CODA 1.0.6 installation package
An update to Notifications API improving the end user experience and fixing issues in the Nokia N9 implementation of the API.

If you already have Qt SDK installed, you can update to the latest version by running Update Qt SDK from the Qt SDK application folder on your computer. If you first time are getting started with Qt SDK, you can download 1.2 from our download page.

If you encounter problems, please file a bug report at http://bugreports.qt-project.org.

Qt Creator 2.4.1 released

2012-02-01T10:34:24+00:00

Today we publish a patch release of Qt Creator 2.4, that is also included in a bigger Qt SDK 1.2 update.

Qt Creator 2.4.1 contains no new features, but fixes a few issues, most notably

finding the QMLViewer.app on case sensitive Mac file systems
building debugging helpers for universal builds, and tool chain / mkspec setting in some configurations (Mac)
automatic proxy detection on Windows systems

Also see the 2.4.1 change log.

Get the new version from our download page, or through the updated SDK here.

LibreTab… not?

2012-01-31T22:06:50+00:00

In a perfectly orchestrated marketing campaign for a 100% free-libre tablet called Spark that will run KDE Plasma Active, Aaron Seigo writes today about the problems they are facing with GPL-violations.

Apparently, every Chinese manufacturer is breaking the GPLv2 by not releasing the sources for their modified Linux kernel. Conversations and conversations with Zenithink (designers of the Spark), Synrgic (designers of the Dreambook W7), etc have arrived nowhere. To the point that CordiaTab, another similar effort using Gnome instead of KDE, has been cancelled.

I have to say I am very surprised at the lack of the kernel sources. What is the Free Software Foundation doing? Why don’t we seek ban of all imports of tablets whose manufacturers don’t release the full GPL source?

Apple got the Samsung GalaxyTab imports blocked in Germany and Australia for something as ethereal as patents covering the external frame design. We are talking about license infringement, which is easier to demonstrate in court.

China may ignore intellectual property but they cannot ignore business, and no imports means no business. Let’s get all GPL-infringing tablet imports banned and we will get more source in two weeks than we can digest in two years. Heck, I’m surprised Apple is not trying this in court to block Android!

GoingNative12 @ KDAB, Berlin

2012-01-31T15:36:26+00:00

For everyone interested in C++11, and as suggested by Herb Sutter, KDAB will show the live stream of the GoingNative12 C++ conference in it’s training facilities at Tempelhofer Ufer 11 in Berlin this Thursday and Friday (Feb 2nd and 3rd). The show is scheduled to run from 18:30 to 02:15 (CET) each day. We invite everyone to join us, but please drop us a note at berlin(at)kdab.com so we can plan ahead.

Filed under: C++0x, English, German

HTML5 for everything?

2012-01-30T01:51:57+00:00

Apparently HTML5 applications are the best thing after sliced bread.

HTML5 is the first platform any mobile vendor supports: iPhone, Android, Windows Phone, BlackBerry, Symbian. All of them.

Windows 8 is said to promote HTML5 as the preferred application development solution.

I used to look kindly at that. But about a month ago I started to get worried: is HTML5 good for everything?

Long-lived applications

In military, industrial, warehouse management, medical, etc is not rare that bespoke applications are developed and stay in use for many years (and I really mean many: 10, 20 or even more!) with barely an update. It’s not rare that those applications only receive very small updates once very 5 years. Those applications, not Angry Birds, are what keeps the world running: troops know what supplies they can count on, iPhones are manufactured, FedEx is able to deliver your package and your doctor is able to check your health.

But now that everybody seems to be moving to HTML5 webapps, what happens when my warehouse management application is a webapp and the additions in the newest browsers make the webapp no longer work?

Are vain upgrades the future?

Say my webapp is released in 2014 and it works fine with Firefox 14.0 and Chrome 26.0, the newest browsers when I release the application in 2014. Fast-forward to 2020 and Firefox 14.0 and Chrome 26.0 do not even install on Windows 10 computer! What’s the solution?

Should the customer pay for a huge update and redesign to make it work with Firefox 27.1 and Chrome 41.0 in 2020?

A virtual machine with Windows 8 and Firefox 14.0? A portable Mozilla Firefox 14.0 on Windows 10 in 2020 to be able to use that line-of-business application that only requires a small update once or twice every 5 years? How are the virtual machine and/or Portable Firefox 14.0 different from or better than a fat client? What’s the advantage? I’d say none!

Native applications usually do not have that kind of problems because APIs are much more stable. You can still run Win16 applications on Windows 7!

You don’t believe me? We may soon be developing for 76 browsers!

While HTML5 may be fine for applications which are updated very often, it makes me feel very uneasy to see it used in environments where applications will be rarely updated, such as SCADAs, warehouse management, control system, medical records, etc.

A solution is needed

It looks like that choice of technology is going to make those applications much more expensive in the medium and long term, paying for “adaptations to new browsers” (sorry, I resist to call “update” or “upgrade” to something that adds zero value other than being able to run on a newer browser).

Or maybe it’s about time to define actual “HTML5 profiles”. ACID3 seems to be too weak of a profile: two very different browsers may pass ACID3 yet a webapp would work with one browser and fail with the other due to bugs, missing features/added features, etc.

Something needs to be done.

Qt Day in Florence, Italy – live and kicking

2012-01-27T13:43:04+00:00

Day one of the Qt Day in Florence, Italy is sold out. The agenda for the day is dedicated to the use of Qt in Italy from a technical as well as business perspective.

Italian business leaders such as Alberto Ciarnello from Telecom Italia and Mario Fumagalli from Mixel have been telling us about why Qt has been a compelling choice for them. We have also heard Italian Qt developers Easy Digital present their shipping Qt based Set-Top Box, and Qt Partner M31 will be demonstrating its Qt-based automation framework.

The conference is organised by Qt Partners with Develer in the lead cooperating with M31 and Digia and Nokia. The set-up of the event is similar to Qt Developer Days and Qt Developer Conferences with its mixture of technical tracks and Qt-in-use sessions. However, this event in Florence is focused on the local developer ecosystem with over 30 sessions delivered mainly in Italian.

During the morning, Nokia’s Manuel Reverte-Castro, Head of Ecosystem Developer Experience for South Europe, took us through the Qt opportunities in the mobile space, providing various examples of developers and companies that make money with Qt on the Nokia store. Burkhard Stubert, from Nokia, also delivered an engaging keynote session about Qt 5 and the Qt Project, and how you make a good ROI from targeting multiple platforms with Qt.

Digia will present the Qt Commercial roadmap and their focus on enhancing Qt for desktop and embedded development pushing forward features and functions that benefit cross-platform development on non-mobile targets.

Developers at the event can take advantage of a real-time help desk staffed by Qt engineers, learn more about licensing, as well as how to become a Qt Ambassador or to sign up to be a Qt Partner.

Tomorrow will feature even more technical sessions, and a fully-fledged community day. We’ll be bringing highlights of both days to you in the coming days.

To learn more about the event, visit http://www.qtday.it

The event also has its own Twitter account – follow @QtDay on Twitter (event hashtag: #QtDayITA)

The Irony of the Real World

2012-01-27T11:29:58+00:00

Qt does not sell mobiles. As a consumer, Qt is a technicality. Right now, the experience and availability of apps sell phones. Qt is just a tool for us developers to implement those experiences. Despite this, it is interesting to compare the Nokia N9 and the new WP7-based Lumia handsets. The market’s reaction to both, and the irony of it all.

Sweden is a highly developed smartphone market. Almost everyone has a smartphone. Flat rate data subscriptions are cheap. Both N9 and Lumia are sold here, and are advertised.

The reviews are interesting. In mobil.se’s comparison, the N9 lose out because the platform is bound to die, thus have fewer apps. In the same organisations yearly awards, the N9 win three out of four applicable categories (the Sony Ericsson Mini Pro won the value-for-your-money-award). The N9 also went straight to the top of the selling charts at katshing.se, and in the telekomidag.se review of Lumia, the final words praise the N9 “Sister model N9 with MeeGo was a (albeit late) eye-opener, for Lumia is feeling more of oh well-character. Skilled in every way - but we have seen most things before.” (google translation of ”Systermodellen N9 med Meego var en (om än för sen) aha-upplevelse, för Lumia blir känslan mer av jaha-karaktär. Kompetent på alla sätt – men vi har ju sett det mesta förut.”)

Following this trail, the latest sad figures from Nokia report that things aren’t going that well. Telling your customers and employees that your current unique product is dead, then delivering a mainstream product later does not help improve business. Bloomberg has looked at various analysts’ estimations of sales figures, and they estimate 1.4 million N9 where sold 2011, while the Lumia is estimated to have sold 1.3 million (estimates range from 800k – 2M).

The interesting part in all these comparisons is that the N9/MeeGo platform is not being pushed by Nokia. They do not want to sell it. The Lumia, on the other hand, is being pushed by the biggest marketing budget Nokia ever has spent on a single product. The Lumia series is being expanded, apps are emerging.

I am sure that Nokia/Microsoft will succeed. I had a VHS system at home, even though Betamax was technically superior. The cost for success will be to turn Nokia from a leading brand into a mainstream supplier, no more important than HTC or Samsung. Sad for Nokia, sad for Finland, sad for what could have been for Qt. Launching N950 alongside N9 and following up with multi-core models would had been great. Also, seeing that MeeGo Harmattan more or less was Maemo with Qt, Intel’s drop-out would not have been the end of the world.

Still, from a Qt developer, this, in combination with the openly governed Qt Project means that Qt will stay a cross platform tool. The risk of seeing it being sucked into a life as a (great!) single platform is no more. Qt/iOS, Qt/Android and Qt/MeeGo give a bigger target area than WP7 has. And if the WP8 platform is to follow desktop, Nokia just jumped from one burning platform to another, since they are going HTML5.

Embedded Linux Development Just Got Easier With with Qt Commercial 4.8 SDK

2012-01-26T14:28:19+00:00

Now that the first Qt Commercial SDK is out, you can also enjoy the improvements we have been doing for embedded Linux development. The Qt Commercial SDK now contains everything you need to start Qt development on popular embedded development...

The First Qt Commercial SDK is now Available for Desktop and Embedded Development

2012-01-26T14:27:27+00:00

T hroughout the latter part of 2011, we have been working with the new Qt Commercial SDK that enables you to install the essential tools and libraries easier than before – and to keep them up to date with new versions. The SDK can be used to devel...

How to Create Qt Applications with Metro Style

2012-01-25T18:18:10+00:00

As the Deploying on Windows 8 Tablets with Qt Commercial blog post demonstrated, the Qt Commercial C++ and Qt Quick applications ran nicely without any problems or modifications on Windows 8 Developer Preview. With this post we are going to show i...

Qt Contributors Day, wikis and the contribution process

2012-01-25T12:56:46+00:00

It’s impossible to do every single thing perfectly when opening up the whole development of Qt. Hence the Qt contribution process has to be improved, helping everyone to make Qt even better. I’ll highlight some the suggestions brought up at Qt Contribution Days. Here is my take on a Troll approach on how to achieve excellence and learning how to make Qt even better than today.

“How can we do this better? Can it be done in a simpler and more elegant way?” are two key questions which have governed the people who have developed Qt from the start. The same goes for learning. We never stop learning. Trolls like to teach themselves new things and learn from each other. A well-meant error is also also key to achieving excellence. We thrive on change and achieve excellence through trying and failing. A well-meant error, on any level, should never be punished, because it is an opportunity for us to learn and improve. Being a contributor to Qt, the values on learning and excellence apply to you too!

Ideas for the contribution process

Several topics at Qt Contributors Days addressed improvements needed to the process, and how to make the contribution process easier. I’ll highlight three of the most significant ones, and urge you to add even more suggestions for improvements at this wiki: Improving The Qt Contribution Process.

The first noteworthy contribution process suggestion at Qt Contributors Day related to making better documentation on porting Qt to a new platform. Using Qt Lighthouse, porting is easier. But it’s still an expert challenge to adapt to a new operating system or platform. Having a migration overview, an architectural guidance, some experiences, would be really appreciated. The notes from the round table on porting challenges between Qt4 and Qt5 explain this idea further.

There are a lot of new contributors joining the Qt project. Having an overview of different activities, module maintainers and such can be time consuming. In some cases you might be even a detective trying to find status and were to begin. A Qt module activity overview inspired by Canonicals Launchpad could address the need for an overview. Aggregating module data from Qt commits, e-mail lists and relevant blog posts on a status page. This includes a list of who has contributed to the module, and who the maintainers are.

Cornelius Schumacher had an interesting suggestion for making a repository automation for Qt add-ons, making it really easy to use complementary libraries. Schumacker labled this as “CPAN for Qt”: a website listing available Qt-based libraries, making it easier for developers to find useful libs and for library developers to promote their work. It’s a really interesting project which can help foster an ecosystem of Qt add-ons.

These are only three humble suggestions on how to improve the Qt and the contribution process. There were of course more issues and features suggested at Qt Contributors Day. I hope also you will contribute your suggestion. Please use this wiki-page suggesting improvements.

People doing useful stuff with my toys

2012-01-25T10:33:23+00:00

About a year ago, I wrote a small web browser, called De Vicenzo just for fun.

But hey, someone went and madeit useful for something! Specifically, to provide previews when doing sphix docs

That's cool :)