QtQuick/QML in a growing project

Some time ago at Open CASCADE we have started a new project called CAD Assistant, which become a small but still powerful 3D viewer and convertor for CAD models (STEP, IGES, BREP) as well as Mesh files (STL, OBJ, PLY, glTF) available on many platforms (Windows, OS X, Android, iOS).

cad_assistant_0-7

Although in Open CASCADE we have developed a plenty of desktop applications before, mobile platforms and touch screen user interface were something new for most of us at that time – and making a new application for Android platform was a challenging but inspiring task. One of the reasons for starting CAD Assistant development was actually porting and testing open-source Open CASCADE Technology framework onto Android platform – including its own 3D visualization toolkit.

After some investigations, we have decided using Qt5/QML framework for the user interface. This decision was not a strong choice, but rather an opportunity to learn more about QtQuick and QML so that to have experience with this technology.

After a couple of years, I have decided writing a small article representing my personal impressions about this technology. This article might be useful for developers deciding upon technologies for starting a new project – there is no direct comparison with other frameworks, but several important aspects good to know at the very beginning.

Go to the article – QtQuick/QML in a growing project.

 

sView and OpenVR

sView 17.01 has been released recently introducing OpenVR support and various improvements for viewing VR360 panoramas.

OpenVR support allows viewing videos and images in HMD devices like HTC Vive – with head tracking support within VR360 panoramas.

New version also introduces support for audio tracking within panoramic videos – a very nice feature for watching video in HMD. This feature requires multi-channel audio streams (it will work with stereo stream, but spatial effect will be very poor in this case). sView now also supports a 4-channel Ambisonic B-Format audio streams – as it supported by OpenAL Soft library through AL_EXT_BFORMAT extension. Ambisonic audio is actually a requirement for uploading videos with spatial audio onto YouTube. Using external tools it is also possible to download VR360 videos with spatial audio from YouTube and play it in sView.

User Ulf Brusquini has prepared a small tutorial for configuring spatial audio playback in sView:

One curious thing about OpenVR is that right now it is not very “open” as it can be deduced from name. In fact it is only SteamVR which can be used with it (and thus requires Steam client to be installed), and OpenVR itself is a draft for open API with only one implementation having no source code.

OpenVR is a Valve initiative for making VR open to everybody (HTC Vive has been developed by HTC and Valve in partnership). And now future of open VR standard in hands of Khronos group – well known consortium developing open standards (like OpenGL). So developers might expect a really open standard which will be accepted by many VR vendors, instead of mess of vendor-locked APIs currently available.

About this blog

Hi, I’m Kirill Gavrilov, software developer and manager currently employed by Open CASCADE (Datavision NN, Nizhny Novgorod).

I’ve decided to start a personal blog, because as many others – I would like to share my personal ideas and experience with others.

3D is an important part of my life – from hobby projects to everyday job. I’ve created and still working on an open-source project sView since ‘2007. sView is a stereoscopic media player and image viewer for 3d stereo and VR. So the main focus of this blog will be on 3D – hence it was named “Unlimited 3D”. Anyway, don’t blame for posing notes not related to this subject directly ;).

I’m also participating in development of Open CASCADE Technology since ‘2009 – both as part of my regular job in Open CASCADE, as well as personal contributions prepared in a spare time. My expertise is focused on 3D here – evolution of 3D Viewer based on OpenGL / OpenGL ES technology.

Since ‘2014 I’m also a one of developers of great freeware 3D Viewer for CAD models – Open CASCADE CAD Assistant available for free on Windows, OS X, Android and iOS platforms.