Fix loading and exporting of Theora and WebM video streams

Theora and WebM video streams were mistakenly imported with a ResourceImporter,
but those imported ogvstr and webmstr were simply links to the local resource.
While that works fine in the editor, it no longer works when exporting a game
as the "source" ogv and webm files are ommitted and only the ogvstr and webmstr
references were exported.

As discussed with @reduz, it doesn't make sense to import videos, as we only
intend to play them back and not modify them/access their raw data. As such we
use a ResourceFormatLoader instead of an importer, to load the file on the fly.
ogv and webm files linked to this loader are now considered as resources, and
thus exported.

Note: The Theora and WebM loaders lack any kind of validity check beyond the
existence of the target file, but it was already the case with the importer.
Better checks and error reports could be added, but those loaders will eventually
be obsoleted by GDNative plugins anyway.

Fixes godotengine#14954.

modules/theora/register_types.cpp

@@ -29,18 +29,22 @@
 /*************************************************************************/
 
 #include "register_types.h"
-#include "resource_importer_theora.h"
+
 #include "video_stream_theora.h"
 
+static ResourceFormatLoaderTheora *resource_loader_theora = NULL;
+
 void register_theora_types() {
 
-#ifdef TOOLS_ENABLED
-	Ref<ResourceImporterTheora> theora_import;
-	theora_import.instance();
-	ResourceFormatImporter::get_singleton()->add_importer(theora_import);
-#endif
+	resource_loader_theora = memnew(ResourceFormatLoaderTheora);
+	ResourceLoader::add_resource_format_loader(resource_loader_theora, true);
+
 	ClassDB::register_class<VideoStreamTheora>();
 }
 
 void unregister_theora_types() {
+
+	if (resource_loader_theora) {
+		memdelete(resource_loader_theora);
+	}
 }

modules/theora/video_stream_theora.cpp

@@ -730,3 +730,46 @@ void VideoStreamTheora::_bind_methods() {
 
 	ADD_PROPERTY(PropertyInfo(Variant::STRING, "file", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_NOEDITOR | PROPERTY_USAGE_INTERNAL), "set_file", "get_file");
 }
+
+////////////
+
+RES ResourceFormatLoaderTheora::load(const String &p_path, const String &p_original_path, Error *r_error) {
+
+	FileAccess *f = FileAccess::open(p_path, FileAccess::READ);
+	if (!f) {
+		if (r_error) {
+			*r_error = ERR_CANT_OPEN;
+		}
+		memdelete(f);
+		return RES();
+	}
+
+	VideoStreamTheora *stream = memnew(VideoStreamTheora);
+	stream->set_file(p_path);
+
+	Ref<VideoStreamTheora> ogv_stream = Ref<VideoStreamTheora>(stream);
+
+	if (r_error) {
+		*r_error = OK;
+	}
+
+	return ogv_stream;
+}
+
+void ResourceFormatLoaderTheora::get_recognized_extensions(List<String> *p_extensions) const {
+
+	p_extensions->push_back("ogv");
+}
+
+bool ResourceFormatLoaderTheora::handles_type(const String &p_type) const {
+
+	return ClassDB::is_parent_class(p_type, "VideoStream");
+}
+
+String ResourceFormatLoaderTheora::get_resource_type(const String &p_path) const {
+
+	String el = p_path.get_extension().to_lower();
+	if (el == "ogv")
+		return "VideoStreamTheora";
+	return "";
+}

modules/theora/video_stream_theora.h

@@ -163,7 +163,7 @@ class VideoStreamPlaybackTheora : public VideoStreamPlayback {
 class VideoStreamTheora : public VideoStream {
 
 	GDCLASS(VideoStreamTheora, VideoStream);
-	RES_BASE_EXTENSION("ogvstr");
+	RES_BASE_EXTENSION("ogv");
 
 	String file;
 	int audio_track;
@@ -186,4 +186,12 @@ class VideoStreamTheora : public VideoStream {
 	VideoStreamTheora() { audio_track = 0; }
 };
 
+class ResourceFormatLoaderTheora : public ResourceFormatLoader {
+public:
+	virtual RES load(const String &p_path, const String &p_original_path = "", Error *r_error = NULL);
+	virtual void get_recognized_extensions(List<String> *p_extensions) const;
+	virtual bool handles_type(const String &p_type) const;
+	virtual String get_resource_type(const String &p_path) const;
+};
+
 #endif

modules/webm/register_types.cpp

@@ -29,18 +29,22 @@
 /*************************************************************************/
 
 #include "register_types.h"
-#include "resource_importer_webm.h"
+
 #include "video_stream_webm.h"
 
+static ResourceFormatLoaderWebm *resource_loader_webm = NULL;
+
 void register_webm_types() {
 
-#ifdef TOOLS_ENABLED
-	Ref<ResourceImporterWebm> webm_import;
-	webm_import.instance();
-	ResourceFormatImporter::get_singleton()->add_importer(webm_import);
-#endif
+	resource_loader_webm = memnew(ResourceFormatLoaderWebm);
+	ResourceLoader::add_resource_format_loader(resource_loader_webm, true);
+
 	ClassDB::register_class<VideoStreamWebm>();
 }
 
 void unregister_webm_types() {
+
+	if (resource_loader_webm) {
+		memdelete(resource_loader_webm);
+	}
 }