libobs: Add obs_source_reset_settings()

Allows the ability to reset (erase) a source's existing settings and
replace them with new settings. This is useful for things such as
reverting to older settings.

docs/sphinx/reference-sources.rst

@@ -818,6 +818,13 @@ General Source Functions
 
 ---------------------
 
+.. function:: void obs_source_reset_settings(obs_source_t *source, obs_data_t *settings)
+
+   Same as :c:func:`obs_source_update`, but clears existing settings
+   first.
+
+---------------------
+
 .. function:: void obs_source_video_render(obs_source_t *source)
 
    Renders a video source.  This will call the

libobs/obs-source.c

@@ -941,6 +941,15 @@ void obs_source_update(obs_source_t *source, obs_data_t *settings)
 	}
 }
 
+void obs_source_reset_settings(obs_source_t *source, obs_data_t *settings)
+{
+	if (!obs_source_valid(source, "obs_source_reset_settings"))
+		return;
+
+	obs_data_clear(source->context.settings);
+	obs_source_update(source, settings);
+}
+
 void obs_source_update_properties(obs_source_t *source)
 {
 	if (!obs_source_valid(source, "obs_source_update_properties"))

libobs/obs.h

@@ -942,6 +942,8 @@ EXPORT obs_properties_t *obs_source_properties(const obs_source_t *source);
 
 /** Updates settings for this source */
 EXPORT void obs_source_update(obs_source_t *source, obs_data_t *settings);
+EXPORT void obs_source_reset_settings(obs_source_t *source,
+				      obs_data_t *settings);
 
 /** Renders a video source. */
 EXPORT void obs_source_video_render(obs_source_t *source);