Re: [PATCH 4/4] qv4l2: add OpenGL video render

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Bård,

On Tuesday 16 July 2013 14:59:04 Bard Eirik Winther wrote:
> On Tuesday, July 16, 2013 02:01:45 PM you wrote:
> > Hi Bård,
> > 
> > Thank you for the patches.
> > 
> > On Tuesday 16 July 2013 13:24:08 Bård Eirik Winther wrote:
> > > The qv4l2 test utility now supports OpenGL-accelerated display of video.
> > > This allows for using the graphics card to render the video content to
> > > screen and to performing color space conversion.
> > > 
> > > Signed-off-by: Bård Eirik Winther <bwinther@cisco.com>
> > > ---
> > > 
> > >  configure.ac                |   8 +-
> > >  utils/qv4l2/Makefile.am     |   9 +-
> > >  utils/qv4l2/capture-win.cpp | 559 +++++++++++++++++++++++++++++++++++--
> > >  utils/qv4l2/capture-win.h   |  81 ++++++-
> > >  utils/qv4l2/qv4l2.cpp       | 173 +++++++++++---
> > >  utils/qv4l2/qv4l2.h         |   8 +
> > >  6 files changed, 782 insertions(+), 56 deletions(-)
> > 
> > Is there a chance you could split the OpenGL code to separate classes, in
> > a
> > separate source file ? This would allow implementing other renderers, such
> > as KMS planes on embedded devices.
> 
> Hi.
> 
> Do you mean to separate the GL class only or all the different
> shaders/renderes as well?

Basically, what would be nice to get is an easy way to extend qv4l2 with 
different renderers. OpenGL is fine on the desktop, but for embedded devices a 
KMS planes backend would work best given the mess that the embedded GPU 
situation is. Instead of adding #ifdef ENABLE_OGL and if (use_ogl) through the 
code, abstracting the rendering code in a separate base class that renderers 
could inherit from would make the code simpler to read, maintain and extend.

I haven't looked at the details so I'm not sure how much work that would be, 
but if the effort is reasonable I think it would be a nice improvement.

-- 
Regards,

Laurent Pinchart