framestream2 (with rigtorp/SPSCQueue)

src/content/sdl_video_frame_stream2.hpp

@@ -0,0 +1,65 @@
+#pragma once
+
+#include "./frame_stream2.hpp"
+
+#include <SDL3/SDL.h>
+
+#include <cstdint>
+#include <thread>
+
+inline void nopSurfaceDestructor(SDL_Surface*) {}
+
+// this is very sdl specific
+struct SDLVideoFrame {
+	// TODO: sequence numbering?
+	uint64_t timestampNS {0};
+
+	std::unique_ptr<SDL_Surface, decltype(&SDL_DestroySurface)> surface {nullptr, &SDL_DestroySurface};
+
+	// special non-owning constructor?
+	SDLVideoFrame(
+		uint64_t ts,
+		SDL_Surface* surf
+	) {
+		timestampNS = ts;
+		surface = {surf, &nopSurfaceDestructor};
+	}
+	// copy
+	SDLVideoFrame(const SDLVideoFrame& other) {
+		timestampNS = other.timestampNS;
+		if (static_cast<bool>(other.surface)) {
+			surface = {
+				SDL_CreateSurface(
+					other.surface->w,
+					other.surface->h,
+					SDL_PIXELFORMAT_RGBA8888 // meh
+				),
+				&SDL_DestroySurface
+			};
+			SDL_BlitSurface(other.surface.get(), nullptr, surface.get(), nullptr);
+		}
+	}
+	SDLVideoFrame& operator=(const SDLVideoFrame& other) = delete;
+};
+
+using SDLVideoFrameStream2Writer = MultiplexedQueuedFrameStream2Writer<SDLVideoFrame>;
+using SDLVideoFrameStream2Reader = SDLVideoFrameStream2Writer::ReaderType;
+
+struct SDLVideoCameraContent : protected SDLVideoFrameStream2Writer {
+	// meh, empty default
+	std::unique_ptr<SDL_Camera, decltype(&SDL_CloseCamera)> _camera {nullptr, &SDL_CloseCamera};
+	std::atomic<bool> _thread_should_quit {false};
+	std::thread _thread;
+
+	// construct source and start thread
+	// TODO: optimize so the thread is not always running
+	SDLVideoCameraContent(void);
+
+	// stops the thread and closes the camera
+	~SDLVideoCameraContent(void);
+
+	// make only some of writer public
+	using SDLVideoFrameStream2Writer::aquireReader;
+	using SDLVideoFrameStream2Writer::releaseReader;
+};
+