c_gst_video_overlay_set_render_rectangle

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
__gshared extern (C)
gboolean function(GstVideoOverlay* overlay, gint x, gint y, gint width, gint height) c_gst_video_overlay_set_render_rectangle;

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