QtDeclarative-2d first code drop!

I have the pleasure to announce the first sourcecode drop of our qtdeclarative (Quick2) renderer for system without GPU's.

The sources

The first push contains the branch "asm" which is a version for ARM systems only. If you want to try it on your system, please note the following:

The screen resolution is hardcoded in QQuickItem and in alphablender.S.

The screen needs to be in 32-bit mode ( fbset -depth 32)

More branches with more generic support will follow soon.

So, instead of complaining that it is not working for you , or that it looks bad , go fork it and make pull requests. The whole idea with releasing this as a opensource project is to make it a community project. More details about how it is built up will be posted here in next week.

This work is funded by FLIR to investigate the possibilities of running a rich UI on simple devices with high performance.




The reference hardware is Freescale i.MX7, but is also tested on much smaller hardware with ARM9 cores.

If you find this effort interesting , have suggestions, want to certify it for your hardware, please tell me:

michael.grunditz@prevas.se , Prevas

i.MX6 Qt Quick2 display mirroring and scaling

This is about  screen mirroring and scaling with Qt Quick2 content on the i.MX6.


The way I did it was to use the IPU's to scale and copy out a grabbed screen image to the second display. The event mechanism was triggered by a Quick property in the Window item.

The linked file isn't the exact source code that went into production, but it shows the how  the mirror / scaling can be done. It contains a nasty goto/label thing ... useful in the context since if something breaks, the IPU tasks needs to be shutdown and not to be started again. 

The performance is quite good thanks to the high performance IPU's. There is some load on the CPU when doing the "grab", but it isn't a problem on a Quad i.MX6


 The sourcecode below can be used under the LGPL v2 or later license. The complete code package is available on request.



qsgthreadedrenderloop.cpp

Qt Declarative 2d on i.MX7

Time for some updates on the Qt Declarative 2d project.

I have recently focused on changing the rendering mechanism to a custom frame buffer hitting solution. The heart of it is a ARM assembler routine for alpha blending that composes the the graphics on to the "window" backbuffer. The assembler runs in circles around Qt's drawImage,
which was the primary composing mechanism I used before the assembler routine.

I am also lucky to have a i.MX7 board for certifying Qt Declarative 2d on. It runs very nicely.

The rssnews demo running on the i.MX7 using Qt Declarative 2d with the new rendering engine:

If you have hardware that you would like that to be certified, please contact me at:

michael.grunditz@prevas.se.

Vacation "Work"

It is vacation time this month and I have spent a lot of time with on of my passions, namely:
The Sinclair QL , or rather its operating system QDOS and its successor SMSQ/E.

The main quest has been to get a dedicated system. I don't have any original QL, they went away many years ago. SMSQ/E is available for many platforms, including Atari ST/TT. I have a Atari 1024STe so I picked that for my first test. Sadly the current builds of SMSQ/E didn't work on it. The testing resulted in more fun! I started to debug SMSQ/E using the sources and the Hatari emulator.

In the meantime I figured out a alternative. The most well known SMSQ/E capable emulators is  QPC . They recently became freeware and I encourage you to try them out. Since I wanted a machine that is dedicated to QL computing I opted for the older DOS QPC1. I found a Celeron 400Mz PC under my desk (!) that have a CF IDE adapter and runs DOS. I took the CF card and plugged it into my CF reader and extracted QPC1 to it from my Mac. It worked on first try in the DOS pc.

QPC1 doesn't multitask, it completely takes over the machine. That was exactly what I wanted.
I am currently busy with getting up a decent install of QL software, slow progress but I am getting there.

And on Atari (old smsq/e) :

Photo on Topas 910 (QtDeclarative-2d)

This shows the calculator demo running on slow and old Toshiba Topas 910.

QtDeclarative on platforms without GLES (Quick2)

We ,Prevas (http://www.prevas.com), have been working on a yet to be released project. Our goal is to have a Quick2 compatible Qt Declarative framework for targets without GLES enabled GPU's. The basic design is:

* The application is a standard Quick2 QML application that can be created with QtCreator.
* The QML code runs inside the standard unaltered QML engine.
* A QML application can be described as a tree of QQuickItems. In the GLES QtDeclarative those are tied to GLES shaders. Within this implementation we have replaced the shaders with Qt 2d drawing methods. When a QQuickItem is shown on the screen it renders itself directly to the QPA back buffer. In this way we can skip a lot of abstraction layers compared to using widgets.


 The result is that we can run many of the Quick2 examples and demos on small ARM targets at a decent speed and with a relatively small cpu usage. The performance can be compared to running Quick2  software rendered on a PC.

This implementation will be , in case of release, pushed to gitorious.org probably with the LGPL license. If someone at Digia "The Qt Company" reads this and have any questions and or objections about the license, just contact me.

 If you are interested to get this project come out of our drawers, leave a comment here and I will contact you. We can help you to adopt this to your hardware and possibly also tune QPA backends for different GPU configurations and even to GPU less targets.

Please note that this project has no connections with and was started long before anything was known about: http://blog.qt.io/blog/2015/01/22/introducing-the-qt-quick-2d-renderer/