[PATCH 2/2] qcam: introduce a command line argument to rotate the viewfinder output

[Laurent Pinchart]

On Thu, Jun 20, 2024 at 04:36:07PM -0500, Joel Selvaraj wrote:
> Sometimes devicetrees may not specify the rotation or incorrectly
> specify it. Introduce a command line argument to quickly test different
> rotations. This also helps in easily identifying the rotation at which
> the camera is mounted if kernel developer doesn't already know it.
> 
> Signed-off-by: Joel Selvaraj <joelselvaraj.oss at gmail.com>
> ---
>  src/apps/qcam/main.cpp        |  3 +++
>  src/apps/qcam/main_window.cpp | 19 +++++++++++++++++++
>  src/apps/qcam/main_window.h   |  1 +
>  3 files changed, 23 insertions(+)
> 
> diff --git a/src/apps/qcam/main.cpp b/src/apps/qcam/main.cpp
> index 9846fba5..9100c69d 100644
> --- a/src/apps/qcam/main.cpp
> +++ b/src/apps/qcam/main.cpp
> @@ -37,6 +37,9 @@ OptionsParser::Options parseOptions(int argc, char *argv[])
>  			 ArgumentRequired, "camera");
>  	parser.addOption(OptHelp, OptionNone, "Display this help message",
>  			 "help");
> +	parser.addOption(OptOrientation, OptionString,
> +			 "Desired image orientation (rot0, rot90, rot180, rot270)",
> +			 "orientation", ArgumentRequired, "orientation");
>  	parser.addOption(OptRenderer, OptionString,
>  			 "Choose the renderer type {qt,gles} (default: qt)",
>  			 "renderer", ArgumentRequired, "renderer");
> diff --git a/src/apps/qcam/main_window.cpp b/src/apps/qcam/main_window.cpp
> index 18c94cf3..aa4a0fa0 100644
> --- a/src/apps/qcam/main_window.cpp
> +++ b/src/apps/qcam/main_window.cpp
> @@ -399,6 +399,25 @@ int MainWindow::startCapture()
>  	if (rotation)
>  		orientation = orientationFromRotation(*rotation);
>  
> +	/* Override if user specifies orientation in command line argument */
> +	if (options_.isSet(OptOrientation)) {
> +		std::string orientOpt = options_[OptOrientation].toString();
> +		static const std::map<std::string, Orientation> possible_orientations{
> +			{ "rot0", Orientation::Rotate0 },
> +			{ "rot90", Orientation::Rotate90 },
> +			{ "rot180", Orientation::Rotate180 },
> +			{ "rot270", Orientation::Rotate270 },
> +		};
> +
> +		auto requested_orientation = possible_orientations.find(orientOpt);
> +		if (requested_orientation == possible_orientations.end()) {
> +			std::cerr << "Unsupported orientation " << orientOpt << std::endl;
> +			return -EINVAL;
> +		}
> +
> +		orientation = requested_orientation->second;

There's similar code in src/apps/cam/camera_session.cpp. Is it worth
moving it to a helper in src/apps/common/ ? options.cpp could be a
suitable candidate.

And I think it would be nice if the argument behaved the same way as in
cam, so it should be used to set config->orientation, overriding the
default Orientation::Rotate0 value.

> +	}
> +
>  	StreamConfiguration &vfConfig = config_->at(0);
>  
>  	/* Use a format supported by the viewfinder if available. */
> diff --git a/src/apps/qcam/main_window.h b/src/apps/qcam/main_window.h
> index 4cead734..6dbcd88d 100644
> --- a/src/apps/qcam/main_window.h
> +++ b/src/apps/qcam/main_window.h
> @@ -40,6 +40,7 @@ class HotplugEvent;
>  enum {
>  	OptCamera = 'c',
>  	OptHelp = 'h',
> +	OptOrientation = 'o',
>  	OptRenderer = 'r',
>  	OptStream = 's',
>  	OptVerbose = 'v',

-- 
Regards,

Laurent Pinchart