[libcamera-devel] [PATCH v4 0/4] generate and use fixed-sized Span Control types

[Kieran Bingham]

Quoting Christian Rauch via libcamera-devel (2022-05-17 23:44:31)
> Hi all,
> 
> Can you let me know what is missing to go forward with this? I think I
> resolved all comments.
> 

The outstanding investigation was not knowing if opencv could support
features from C++17.

It looks like they use C++11, and we're already using C++14 - so this
may mean that it is already not possible for open-cv to implement a
libcamera plugin directly until they update their C++ standard.

The difficulty is, as a library that could be widely used - to support
more projects would require conservative updating of the C++ standard.
So somehow we have to decide when we can use C++ 17 features on our
public API.

We could also simply choose to do so - and therefore enforce any
projects that want to use libcamera to update... For applciations that's
probably trivial - but for other libraries, like opencv, well then they
face the same issue - that they might not be able to update easily.

--
Kieran

> Best,
> Christian
> 
> 
> Am 27.04.22 um 23:30 schrieb Christian Rauch:
> > Hello,
> >
> > In version 4 of this patch set I applied minor modification from feedback that I received so far. I reorderd the commits such that the "std::optional" commit appears first and can be used without the changes related to fixed-sized Spans.
> >
> > Best,
> >
> > Christian Rauch (4):
> >   use std::optional to handle invalid control values
> >   libcamera: controls: Define size of array controls as a shape vector
> >   generate fixed- and variable-sized Span Controls
> >   apply explicit fixed-sized Span type casts
> >
> >  include/libcamera/controls.h                  |  7 ++--
> >  src/cam/main.cpp                              |  4 +--
> >  src/ipa/raspberrypi/raspberrypi.cpp           | 21 ++++++------
> >  src/libcamera/control_ids.yaml                |  2 +-
> >  src/libcamera/pipeline/ipu3/ipu3.cpp          |  9 +++---
> >  .../pipeline/raspberrypi/raspberrypi.cpp      | 10 +++---
> >  src/libcamera/property_ids.yaml               |  4 +--
> >  src/qcam/dng_writer.cpp                       | 15 +++++----
> >  utils/gen-controls.py                         | 32 +++++++++++++------
> >  9 files changed, 61 insertions(+), 43 deletions(-)
> >
> > --
> > 2.34.1