On Tue, Nov 26, 2013 at 4:12 PM, Alexandros Frantzis <alexandros.frant...@canonical.com> wrote: > On Tue, Nov 26, 2013 at 01:13:28PM +0000, Gerry Boland wrote: >> Hey, >> The system compositor will probably not be using the Qt scenegraph, but >> instead Mir's own compositor. I don't know if using >> QQuickWindow::grabWindow() will work in that case (though if it just >> calls glReadPixels, it probably will). >> >> Also if hardware (non-GL) compositing is being used, reading back pixels >> via glReadPixels won't be enough as not everything on screen will be >> drawn by GL. >> >> As a result, I'm not certain we can rely on QQuickWindow::grabWindow() / >> glReadPixels, but would need something internal to Mir. >> > > In general, graphics cards and drivers don't offer access to the final > output buffer (after HW compositing), at least not through a standard > API (I don't know if Android drivers offer such functionality). Even if > we move the screenshoting functionality into Mir, it's probable that the > best we will be able to do is to recomposite everything using OpenGL and > read back the pixels. > > Perhaps what could happen is that when Unity8 wants to take a screenshot > it can tell Mir to composite everything with OpenGL for the current > frame. > > The original discussion was about autopilot being able to take > screenshots/casts of unity8 for testing and validation purposes, and we > came up with a simple solution for this use case. >
That's a fair point. As I understand it, there is the immediate requirement to support QA with screenshotting capabilities and the presented approach can be used to provide the required functionality. > However, it seems that people have more use cases for screen capturing > that require additional complexity. I think we need to discuss a bit > more about what we really need and when, check what is feasible in our > time frames and prioritize work. The upcoming sprint seems ideal for > this. > +1. Cheers, Thomas > Thanks, > Alexandros > > -- > Mir-devel mailing list > Mir-devel@lists.ubuntu.com > Modify settings or unsubscribe at: > https://lists.ubuntu.com/mailman/listinfo/mir-devel -- Mir-devel mailing list Mir-devel@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/mir-devel
