osc.lua: add osd-margin option

Fixes: #17539

DOCS/interface-changes/osc-margins.txt

@@ -1,2 +1,3 @@
 add `osc-dynamic_margins` option
 add `osc-sub-margin` option
+add `osc-osd-margin` option

DOCS/man/osc.rst

@@ -420,6 +420,15 @@ Configurable Options
     already confined to the video area and this option has no additional
     effect.
 
+``osd_margins``
+    Default: yes
+
+    Whether to adjust ``--osd-margin-y`` so that OSD text does not overlap
+    with the OSC. The offset is derived from the top OSC margin (including
+    window controls when present) and added on top of the current
+    ``--osd-margin-y`` value. Requires ``dynamic_margins`` or
+    ``visibility=always`` to take effect.
+
 ``windowcontrols``
     Default: auto (Show window controls if there is no window border)
 

player/lua/osc.lua

@@ -50,6 +50,7 @@ local user_opts = {
     boxvideo = false,           -- apply osc_param.video_margins to video
     dynamic_margins = false,    -- update margins dynamically with OSC visibility
     sub_margins = true,         -- adjust sub-margin-y to not overlap with OSC
+    osd_margins = true,         -- adjust osd-margin-y to not overlap with OSC
     windowcontrols = "auto",    -- whether to show window controls
     windowcontrols_alignment = "right", -- which side to show window controls on
     windowcontrols_title = "${media-title}", -- same as title but for windowcontrols
@@ -562,6 +563,7 @@ local function reset_margins()
         state.using_video_margins = false
     end
     set_margin_offset("sub-margin-y", 0)
+    set_margin_offset("osd-margin-y", 0)
 end
 
 local function update_margins()
@@ -616,6 +618,7 @@ local function update_margins()
         return margin * osc_param.playresy
     end
     set_margin_offset("sub-margin-y", get_margin("sub"))
+    set_margin_offset("osd-margin-y", get_margin("osd"))
 
     mp.set_property_native("user-data/osc/margins", margins)
 end