aspect: add video margin options

Semantics a bit questionable. This is done for the OSC (next commit),
and a comment added the manpage explicitly states this. Meaning this is
probably garbage and needs to revisit when the OSC changes and/or
someone wants to use this margin feature for something else.

Not sure about the subtitle thing. It's imaginable that someone uses
these options to create empty borders for subtitles on the bottom, so
subtitles should be located there. On the other hand, this gives a
rather unpolished user experience when using the (later added) OSC
feature to not overlap with the video. There's not much of a point if
the OSC still overlaps the video. However, I'm too lazy to think about
this, so it stays like it is.

1 files changed, 2 insertions, 0 deletions

diff --git a/options/options.h b/options/options.h
index 182b901cd4..1f78dd9303 100644
--- a/options/options.h
+++ b/options/options.h
@@ -29,6 +29,8 @@ typedef struct mp_vo_opts {
     float zoom;
     float pan_x, pan_y;
     float align_x, align_y;
+    float margin_x[2];
+    float margin_y[2];
     int unscaled;
 
     struct m_geometry geometry;