extract sdl cameras creation/deletion to service

and handle events

src/frame_streams/sdl/sdl_video_input_service.cpp

@@ -0,0 +1,114 @@
+#include "./sdl_video_input_service.hpp"
+
+#include <solanaceae/object_store/object_store.hpp>
+
+#include "../stream_manager.hpp"
+#include "./sdl_video_frame_stream2.hpp"
+
+#include <iostream>
+
+namespace Components {
+
+	struct SDLVideoDevice {
+		SDL_CameraID device;
+	};
+
+} // Components
+
+bool SDLVideoInputService::addDevice(SDL_CameraID device) {
+	const char *name = SDL_GetCameraName(device);
+	std::cout << "  - Camera #" << device << ": " << name << "\n";
+
+	int speccount {0};
+	SDL_CameraSpec** specs = SDL_GetCameraSupportedFormats(device, &speccount);
+	if (specs == nullptr) {
+		std::cout << "    - no supported spec\n";
+		return false;
+	} else {
+		for (int spec_i = 0; spec_i < speccount; spec_i++) {
+			std::cout << "    - " << specs[spec_i]->width << "x" << specs[spec_i]->height << "@" << float(specs[spec_i]->framerate_numerator)/specs[spec_i]->framerate_denominator << "fps " << SDL_GetPixelFormatName(specs[spec_i]->format) << "\n";
+
+		}
+		SDL_free(specs);
+
+		// create sink for device
+		ObjectHandle vsrc {_os.registry(), _os.registry().create()};
+		try {
+			vsrc.emplace<Components::SDLVideoDevice>(device);
+
+			vsrc.emplace<Components::FrameStream2Source<SDLVideoFrame>>(
+				std::make_unique<SDLVideo2InputDevice>(device)
+			);
+
+			vsrc.emplace<Components::StreamSource>(Components::StreamSource::create<SDLVideoFrame>("SDL Video '" + std::string(name) + "'"));
+			//vsrc.emplace<Components::TagDefaultTarget>();
+
+			_os.throwEventConstruct(vsrc);
+			//last_src = vsrc;
+		} catch (...) {
+			std::cerr << "SDLVIS error: failed constructing video input source\n";
+			_os.registry().destroy(vsrc);
+			return false;
+		}
+	}
+	return true;
+}
+
+bool SDLVideoInputService::removeDevice(SDL_CameraID device) {
+	for (const auto&& [ov, svd] : _os.registry().view<Components::SDLVideoDevice>().each()) {
+		if (svd.device == device) {
+			_os.throwEventDestroy(ov);
+			_os.registry().destroy(ov);
+			return true;
+		}
+	}
+	return false; // not found ??
+}
+
+SDLVideoInputService::SDLVideoInputService(ObjectStore2& os) :
+	_os(os)
+{
+	if (!SDL_InitSubSystem(SDL_INIT_CAMERA)) {
+		std::cerr << "SDLVIS warning: no sdl camera: " << SDL_GetError() << "\n";
+		return;
+	}
+	_subsystem_init = true;
+	std::cout << "SDLVIS: SDL Camera Driver: " << SDL_GetCurrentCameraDriver() << "\n";
+
+	// sdl throws all cameras as added events anyway
+#if 0
+	int devcount {0};
+	SDL_CameraID *devices = SDL_GetCameras(&devcount);
+
+	std::cout << "SDLVIS: found cameras:\n";
+	if (devices != nullptr) {
+		ObjectHandle last_src{};
+		for (int i = 0; i < devcount; i++) {
+			addDevice(devices[i]);
+		}
+
+		SDL_free(devices);
+	} else {
+		std::cout << "  none\n";
+	}
+#endif
+}
+
+SDLVideoInputService::~SDLVideoInputService(void) {
+	if (_subsystem_init) {
+		SDL_QuitSubSystem(SDL_INIT_CAMERA);
+	}
+}
+
+bool SDLVideoInputService::handleEvent(SDL_Event& e) {
+	if (e.type == SDL_EVENT_CAMERA_DEVICE_ADDED) {
+		std::cout << "SDLVIS: camera added:\n";
+		return addDevice(e.cdevice.which);
+	} else if (e.type == SDL_EVENT_CAMERA_DEVICE_REMOVED) {
+		std::cout << "SDLVIS: camera removed\n";
+		return removeDevice(e.cdevice.which);
+	}
+
+	return false;
+}
+