Revert "Decklink separation"

This reverts commit 46f2f1ece5.

apps/LoopThroughWithOpenGLCompositing/gl/OpenGLComposite.cpp

@@ -83,7 +83,6 @@ bool OpenGLComposite::InitializeVideoIO()
 	}
 
 	const VideoIOConfiguration videoIOConfig = mRuntimeHost->GetVideoIOConfiguration();
-	const VideoIOBackendDescriptor* backendDescriptor = GetVideoIOBackendDescriptor(videoIOConfig.backendId);
 	mVideoIO = CreateVideoIODevice(videoIOConfig.backendId, initFailureReason);
 	if (!mVideoIO)
 	{
@@ -94,8 +93,8 @@ bool OpenGLComposite::InitializeVideoIO()
 
 	if (!mVideoIO->DiscoverDevicesAndModes(videoIOConfig, initFailureReason))
 	{
-		const char* title = IsVideoIOBackendUnavailableError(videoIOConfig.backendId, initFailureReason) && backendDescriptor != nullptr
+		const char* title = initFailureReason == "Please install the Blackmagic DeckLink drivers to use the features of this application."
-			? backendDescriptor->unavailableTitle
+			? "This application requires the selected video I/O drivers installed."
 			: "Video I/O initialization failed";
 		MessageBoxA(NULL, initFailureReason.c_str(), title, MB_OK | MB_ICONERROR);
 		return false;

apps/LoopThroughWithOpenGLCompositing/videoio/VideoIOBackendFactory.cpp

@@ -3,73 +3,14 @@
 #include "DeckLinkSession.h"
 #include "VideoIOTypes.h"
 
-#include <array>
-
-namespace
-{
-struct VideoIOBackendRegistration
-{
-	VideoIOBackendDescriptor descriptor;
-	VideoIODeviceFactory factory;
-};
-
-const std::array<VideoIOBackendRegistration, 1>& RegisteredBackends()
-{
-	static const std::array<VideoIOBackendRegistration, 1> backends = { {
-		{
-			{
-				VideoIOBackendId::DeckLink,
-				"decklink",
-				"Blackmagic DeckLink",
-				"Please install the Blackmagic DeckLink drivers to use the features of this application.",
-				"This application requires the selected video I/O drivers installed."
-			},
-			[]() { return std::make_unique<DeckLinkSession>(); }
-		}
-	} };
-	return backends;
-}
-}
-
-const VideoIOBackendDescriptor* GetVideoIOBackendDescriptor(VideoIOBackendId backendId)
-{
-	for (const VideoIOBackendRegistration& registration : RegisteredBackends())
-	{
-		if (registration.descriptor.backendId == backendId)
-			return &registration.descriptor;
-	}
-	return nullptr;
-}
-
-std::vector<VideoIOBackendDescriptor> ListVideoIOBackendDescriptors()
-{
-	std::vector<VideoIOBackendDescriptor> descriptors;
-	descriptors.reserve(RegisteredBackends().size());
-	for (const VideoIOBackendRegistration& registration : RegisteredBackends())
-		descriptors.push_back(registration.descriptor);
-	return descriptors;
-}
-
 std::unique_ptr<VideoIODevice> CreateVideoIODevice(VideoIOBackendId backendId, std::string& error)
 {
-	for (const VideoIOBackendRegistration& registration : RegisteredBackends())
+	switch (backendId)
 	{
-		if (registration.descriptor.backendId != backendId)
+	case VideoIOBackendId::DeckLink:
-			continue;
+		return std::make_unique<DeckLinkSession>();
-
-		error.clear();
-		return registration.factory ? registration.factory() : nullptr;
 	}
 
 	error = "Unsupported video I/O backend.";
 	return nullptr;
 }
-
-bool IsVideoIOBackendUnavailableError(VideoIOBackendId backendId, const std::string& error)
-{
-	const VideoIOBackendDescriptor* descriptor = GetVideoIOBackendDescriptor(backendId);
-	return descriptor != nullptr &&
-		descriptor->unavailableMessage != nullptr &&
-		*descriptor->unavailableMessage != '\0' &&
-		error == descriptor->unavailableMessage;
-}

apps/LoopThroughWithOpenGLCompositing/videoio/VideoIOBackendFactory.h

@@ -2,25 +2,9 @@
 
 #include "VideoIOConfig.h"
 
-#include <functional>
 #include <memory>
 #include <string>
-#include <vector>
 
 class VideoIODevice;
 
-struct VideoIOBackendDescriptor
-{
-	VideoIOBackendId backendId = VideoIOBackendId::DeckLink;
-	const char* backendName = "decklink";
-	const char* displayName = "Blackmagic DeckLink";
-	const char* unavailableMessage = "";
-	const char* unavailableTitle = "Video I/O initialization failed";
-};
-
-using VideoIODeviceFactory = std::function<std::unique_ptr<VideoIODevice>()>;
-
-const VideoIOBackendDescriptor* GetVideoIOBackendDescriptor(VideoIOBackendId backendId);
-std::vector<VideoIOBackendDescriptor> ListVideoIOBackendDescriptors();
 std::unique_ptr<VideoIODevice> CreateVideoIODevice(VideoIOBackendId backendId, std::string& error);
-bool IsVideoIOBackendUnavailableError(VideoIOBackendId backendId, const std::string& error);

tests/VideoIOBackendFactoryTests.cpp

@@ -19,18 +19,6 @@ void Expect(bool condition, const char* message)
 
 int main()
 {
-	const std::vector<VideoIOBackendDescriptor> backends = ListVideoIOBackendDescriptors();
-	Expect(!backends.empty(), "backend registry is not empty");
-	Expect(backends.front().backendId == VideoIOBackendId::DeckLink, "decklink is registered");
-	Expect(std::string(backends.front().backendName) == "decklink", "decklink registry name is stable");
-
-	const VideoIOBackendDescriptor* descriptor = GetVideoIOBackendDescriptor(VideoIOBackendId::DeckLink);
-	Expect(descriptor != nullptr, "decklink descriptor can be looked up");
-	Expect(descriptor != nullptr && std::string(descriptor->displayName) == "Blackmagic DeckLink", "decklink descriptor exposes display name");
-	Expect(descriptor != nullptr && std::string(descriptor->unavailableTitle) == "This application requires the selected video I/O drivers installed.", "decklink descriptor exposes unavailable title");
-	Expect(IsVideoIOBackendUnavailableError(VideoIOBackendId::DeckLink, "Please install the Blackmagic DeckLink drivers to use the features of this application."), "decklink unavailable message is recognized");
-	Expect(!IsVideoIOBackendUnavailableError(VideoIOBackendId::DeckLink, "some other error"), "non-driver errors are not treated as backend unavailable");
-
 	std::string error;
 	std::unique_ptr<VideoIODevice> device = CreateVideoIODevice(VideoIOBackendId::DeckLink, error);
 	Expect(device != nullptr, "decklink backend factory returns a device");