console.lua: improve the hovered item calculation

Currently determine_hovered_item() assumes that each item is
opts.font_size pixels tall, which usually works well. This breaks with
fonts that get drawn taller than that, such as Japanese text, which
makes the calculation inaccurate for the top items and clips the
counter. A couple of users reported that it is inaccurate for them for
the top items even with ASCII characters in track selectors, presumably
because the circles are taken from a different font and make all lines
taller.

To fix this place each selectable item in its own ASS event positioned
like determine_hovered_item() expects.

Unfortunately this breaks --profile=box, so keep placing every item in
one ASS event with it.

player/lua/console.lua

@@ -601,9 +601,24 @@ local function update()
 
     local log_ass = ''
     local log_buffer = log_buffers[id]
+    local box = mp.get_property('osd-border-style') == 'background-box'
+
     for i = #log_buffer - math.min(max_lines, #log_buffer) + 1, #log_buffer do
-        log_ass = log_ass .. style .. log_buffer[i].style ..
-                  ass_escape(log_buffer[i].text) .. '\\N'
+        local log_item = style .. log_buffer[i].style .. ass_escape(log_buffer[i].text)
+
+        -- Put every selectable item in its own event to prevent libass from
+        -- drawing them taller than opts.font_size with taller fonts, which
+        -- makes the hovered item calculation inaccurate and clips the counter.
+        -- But not with background-box, because it makes it look bad by
+        -- overlapping the semitransparent backgrounds of every line.
+        if selectable_items and not box then
+            ass:new_event()
+            ass:an(1)
+            ass:pos(x, y - (1.5 + #log_buffer - i) * opts.font_size)
+            ass:append(log_item)
+        else
+            log_ass = log_ass .. log_item .. '\\N'
+        end
     end
 
     ass:new_event()