Re: [Interest] Qt3D Reading from a Compute Shader
Hi, I was able to build 5.9a (93b18e36e4cee7daccb24b986823360d1707c0a4), but my build can't seem to find the BufferCapture QML object. The file itself exists, i.e. /home/matt/usr/local/Qt-5.9.0/include/Qt3DRender/5.9.0/Qt3DRender/private/buffercapture_p.h And I'm able to build against Qt5.9 in that directory, everything else seems to work, but it simply won't find that QML object. I'm using CMake as my build system, is there something special I have to do to find this object? This is my first time running Qt from a build from source. Thanks, From: Interest [mailto:interest-bounces+mrussell=neptec@qt-project.org] On Behalf Of Juan José Casafranca Sent: Wednesday, March 1, 2017 6:15 PM To: interest@qt-project.org Subject: Re: [Interest] Qt3D Reading from a Compute Shader I wrote a patch for this some weeks ago. I think is already merged in Qt 5.9. Have a look at the buffercapture example (qt5/qt3d/tests/manual/buffercapture-qml). Let me know if you have any trouble. On miércoles, 1 de marzo de 2017 22:09:15 (CET) Russell, Matthew wrote: > Hi, > > Is it possible with QML to read a buffer operated on by a compute shader? > > If I understood this message properly, > http://lists.qt-project.org/pipermail/interest/2016-November/025167.html , > then this wasn't possible in 5.8, but might be available in 5.9. > > Specifically, I'm showing point data from a lidar in a multi viewport > Scene3d. My Buffer is used in a Geometry that has a Material on it that > performs a compute shader in the first pass, and then passes that data to > the vertex shaders. > > My problem is that as I receive new point data from the lidar, I need to > re-write my data, but I wanna capture the modifications the compute shader > performed. Otherwise, the compute shader translates my point data > properly, but when I re-push my buffer, all the translations are forgotten. > > Thanks. ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] Issue with expanding an environmental variable.
Are you using QString::fromUtf8 to decode the received QByteArray? On Friday, March 03, 2017 04:35:50 PM jschneider...@gog.com wrote: > In an application we’re developing, we need to expand some environmental > variables. We’re using the Qt 5.6 function qgetenv to do that. However, on > our test code when an environmental variable contains some non-ANSI > characters, e.g. Ξ♣♤ᛝᛞ๏฿Ξ , it is expanded to ?¦?? . These are the > contents we see when viewing it in the Visual Studio Debugger. Is this a > known issue or perhaps something we’re doing incorrectly? > > Thanks, > > John Schneiderman > Senior Software Engineer > GOG.com > -- Best regards, Jesus ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
[Interest] Issue with expanding an environmental variable.
In an application we’re developing, we need to expand some environmental variables. We’re using the Qt 5.6 function qgetenv to do that. However, on our test code when an environmental variable contains some non-ANSI characters, e.g. Ξ♣♤ᛝᛞ๏฿Ξ , it is expanded to ?¦?? . These are the contents we see when viewing it in the Visual Studio Debugger. Is this a known issue or perhaps something we’re doing incorrectly? Thanks, John Schneiderman Senior Software Engineer GOG.com ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] Mixing OpenGL and QPainter in QOpenGLWidget
Sounds like you're running into the
OSX-only-supports-core-profile-so-qpainter-on-opengl-widget-doesn't-work
bug. That got fixed last summer by Julian Thijssen during his
summer-of-code project and the patch has been merged for Qt 5.9.
https://codereview.qt-project.org/#/c/166202/
https://bugreports.qt.io/browse/QTBUG-33535
Boud
On Thu, 2 Mar 2017, Jan Müller wrote:
> Hello,
>
> When I use both OpenGL rendering and QPainter calls in the paintGL function
> of a QOpenGLWidget class, I get an OpenGL error code (1282) when checking
> glGetError().
>
> The painting still works, i.e. what I want to draw correctly appears on the
> screen.
>
> Also, this error code only appears on MacOSX. On Linux, it works fine.
>
> Should I be concerned about that error code? It does not feel good and I'm
> really thinking there should not be any error at all in the OpenGL
> rendering.
>
> I'm mainly concerned about this error, because I have a larger, more
> complex application where I use multiple QOpenGLWidgets and switch between
> them (through a QStackedLayout) and there the whole window 'flickers' and
> misbehaves (i.e. does not render correctly). It is hard to search for
> OpenGL errors in my larger application, because I always get this 1282
> error code, like I get it in the simple example shown below.
>
>
> I made a minimal example, just creating and showing a widget derived from
> QOpenGLWidget in main(). The code is here:
>
> https://gist.github.com/anonymous/625e69dd61f0685c1cae625bdefbac74
>
> In the widget, I reimplemented initializeGL, resizeGL, paintGL.
>
> The paintGL function looks like this:
>
> void paintGL() {
> qDebug() << "Error 1:" << glGetError();
> glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
> glBegin(GL_TRIANGLES);
> glColor3f(1.0f, 0.0, 0.0);
> glVertex3f(-0.5f, -0.5f, 0);
> glColor3f(0.0, 1.0f, 0.0);
> glVertex3f(0.5f, -0.5f, 0.0);
> glColor3f(0.0, 0.0, 1.0);
> glVertex3f(0.0, 0.5f, 0);
> glEnd();
>
> QPainter p(this);
> p.setPen(Qt::red);
> p.drawLine(rect().topLeft(), rect().bottomRight());
> qDebug() << "Error 2: " << glGetError();
> }
>
> Strangely, the output I get is this:
>
> Error 1: 0
> Error 2: 0
> Error 1: 1282
> Error 2: 0
> Error 1: 1282
> Error 2: 0
>
> So the first time, no error happens but the second time, there is an error.
> When I comment out QPainter and its two calls, the error code is "gone"
> (always 0). But when I comment out the OpenGL calls but keep the QPainter
> statements, the error is still there.
>
> Do I miss something? Any ideas how to debug? Should I be concerned about
> that error code or should I just ignore it? Could it be (one of the)
> sources of my more substantial OpenGL errors in my larger application?
>
> I'm using Qt 5.7. And as I've said, it only seem to appear on MacOSX.
>
> Thanks for any feedback!
>
>
> Best,
> Jan
>
--
Boudewijn Rempt | http://www.krita.org, http://www.valdyas.org___
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