libobs: Make obs_source_default_render exported

Allows directly rendering a non-async source without going through
filters.

libobs/obs-source.c

@@ -1695,7 +1695,7 @@ static inline void obs_source_render_filters(obs_source_t *source)
 	source->rendering_filter = false;
 }
 
-static void obs_source_default_render(obs_source_t *source)
+void obs_source_default_render(obs_source_t *source)
 {
 	gs_effect_t    *effect     = obs->video.default_effect;
 	gs_technique_t *tech       = gs_effect_get_technique(effect, "Draw");

libobs/obs.h

@@ -771,6 +771,9 @@ EXPORT obs_source_t *obs_filter_get_parent(const obs_source_t *filter);
  */
 EXPORT obs_source_t *obs_filter_get_target(const obs_source_t *filter);
 
+/** Used to directly render a non-async source without any filter processing */
+EXPORT void obs_source_default_render(obs_source_t *source);
+
 /** Adds a filter to the source (which is used whenever the source is used) */
 EXPORT void obs_source_filter_add(obs_source_t *source, obs_source_t *filter);