osc.lua: cache observed properties

For properties that were already being observed but still retrieved over
and over, cache their values using the new observe_cached().

osd-dimensions observer said that if cached we may have to worry about
property ordering but it seems to work fine. It is nice to cache it
because it was the property retrieved the most frequently, in 5
different places.

Author: guidocella

player/lua/osc.lua

@@ -312,6 +312,13 @@ local state = {
     sub_track_count = 0,
     current_tracks = {},
     no_video = false,
+    playlist_count = 0,
+    playlist_pos_1 = 0,
+    pause = false,
+    volume = 0,
+    mute = false,
+    osd_dimensions = {w = 0, h = 0, aspect = 0},
+    osd_scale_by_window = false,
     file_loaded = false,
     enabled = true,
     input_enabled = true,
@@ -400,11 +407,11 @@ end
 
 -- scale factor for translating between real and virtual ASS coordinates
 local function get_virt_scale_factor()
-    local w, h = mp.get_osd_size()
-    if w <= 0 or h <= 0 then
+    if state.osd_dimensions.w == 0 or state.osd_dimensions.h == 0 then
         return 0, 0
     end
-    return osc_param.playresx / w, osc_param.playresy / h
+    return osc_param.playresx / state.osd_dimensions.w,
+           osc_param.playresy / state.osd_dimensions.h
 end
 
 local function recently_touched()
@@ -1189,13 +1196,12 @@ local function render_elements(master_ass)
                     mp.set_property_number("user-data/osc/hover-sec", hover_sec)
 
                     -- thumbnail
-                    local osd_w, osd_h = mp.get_osd_size()
                     local vop = mp.get_property_native("video-out-params")
-                    local draw_thumbnail = osd_w > 0 and vop
+                    local draw_thumbnail = state.osd_dimensions.w > 0 and vop
                     if draw_thumbnail then
                         local r_w, r_h = get_virt_scale_factor()
                         local thumb_max = math.min(user_opts.max_thumb_size,
-                            math.min(osd_w, osd_h) * 0.25)
+                            math.min(state.osd_dimensions.w, state.osd_dimensions.h) * 0.25)
                         local scale = thumb_max / math.max(vop.dw, vop.dh)
                         local thumb_w = math.floor(vop.dw * scale + 0.5)
                         local thumb_h = math.floor(vop.dh * scale + 0.5)
@@ -1207,7 +1213,7 @@ local function render_elements(master_ass)
                         local thumb_pad = 4
                         local thumb_margin_x = 20 / r_w
                         local thumb_margin_y = (4 + user_opts.tooltipborder) / r_h + thumb_pad
-                        local thumb_x = math.min(osd_w - thumb_w - thumb_margin_x,
+                        local thumb_x = math.min(state.osd_dimensions.w - thumb_w - thumb_margin_x,
                             math.max(thumb_margin_x, thumb_tx / r_w - thumb_w / 2))
                         local thumb_y = thumb_ty / r_h + (user_opts.layout ~= "topbar" and
                             -(thumb_h + tooltip_font_size / r_h + thumb_margin_y) or
@@ -2299,7 +2305,6 @@ local function osc_init()
 
     -- set canvas resolution according to display aspect and scaling setting
     local baseResY = 720
-    local _, display_h, display_aspect = mp.get_osd_size()
     local scale
 
     if state.fullscreen then
@@ -2310,19 +2315,19 @@ local function osc_init()
 
     local scale_with_video
     if user_opts.vidscale == "auto" then
-        scale_with_video = mp.get_property_native("osd-scale-by-window")
+        scale_with_video = state.osd_scale_by_window
     else
         scale_with_video = user_opts.vidscale == "yes"
     end
 
     if scale_with_video then
         osc_param.unscaled_y = baseResY
     else
-        osc_param.unscaled_y = display_h
+        osc_param.unscaled_y = state.osd_dimensions.h
     end
     osc_param.playresy = osc_param.unscaled_y / scale
-    if display_aspect > 0 then
-        osc_param.display_aspect = display_aspect
+    if state.osd_dimensions.aspect > 0 then
+        osc_param.display_aspect = state.osd_dimensions.aspect
     end
     osc_param.playresx = osc_param.playresy * osc_param.display_aspect
 
@@ -2334,9 +2339,6 @@ local function osc_init()
     elements = {}
 
     -- some often needed stuff
-    local pl_count = mp.get_property_number("playlist-count", 0)
-    local have_pl = (pl_count > 1)
-    local pl_pos = mp.get_property_number("playlist-pos", 0) + 1
     local have_ch = (mp.get_property_number("chapters", 0) > 0)
     local loop = mp.get_property("loop-playlist", "no")
 
@@ -2364,14 +2366,15 @@ local function osc_init()
     ne = new_element("playlist_prev", "button")
 
     ne.content = icons.prev
-    ne.enabled = (pl_pos > 1) or (loop ~= "no")
+    ne.enabled = state.playlist_pos_1 > 1 or loop ~= "no"
     bind_mouse_buttons("playlist_prev")
 
     --next
     ne = new_element("playlist_next", "button")
 
     ne.content = icons.next
-    ne.enabled = (have_pl and (pl_pos < pl_count)) or (loop ~= "no")
+    ne.enabled = (state.playlist_count > 1 and state.playlist_pos_1 < state.playlist_count)
+                 or loop ~= "no"
     bind_mouse_buttons("playlist_next")
 
 
@@ -2385,7 +2388,7 @@ local function osc_init()
             return icons.clock
         end
 
-        if not mp.get_property_native("pause") then
+        if not state.pause then
             return icons.pause
         end
 
@@ -2643,12 +2646,11 @@ local function osc_init()
     ne = new_element("volume", "button")
 
     ne.content = function()
-        local volume = mp.get_property_number("volume")
-        if volume == 0 or mp.get_property_native("mute") then
+        if state.volume == 0 or state.mute then
             return icons.mute
         end
 
-        return icons.volume[math.min(4, math.ceil(volume / (100/3)))]
+        return icons.volume[math.min(4, math.ceil(state.volume / (100/3)))]
     end
     bind_mouse_buttons("volume")
 
@@ -2897,18 +2899,17 @@ end
 
 local function render()
     msg.trace("rendering")
-    local current_screen_sizeX, current_screen_sizeY = mp.get_osd_size()
     local mouseX, mouseY = get_virt_mouse_pos()
     local now = mp.get_time()
 
     -- check if display changed, if so request reinit
-    if state.screen_sizeX ~= current_screen_sizeX
-        or state.screen_sizeY ~= current_screen_sizeY then
+    if state.screen_sizeX ~= state.osd_dimensions.w
+        or state.screen_sizeY ~= state.osd_dimensions.h then
 
         request_init_resize()
 
-        state.screen_sizeX = current_screen_sizeX
-        state.screen_sizeY = current_screen_sizeY
+        state.screen_sizeX = state.osd_dimensions.w
+        state.screen_sizeY = state.osd_dimensions.h
     end
 
     -- init management
@@ -3044,12 +3045,11 @@ local function render()
 end
 
 local function render_logo()
-    local _, _, display_aspect = mp.get_osd_size()
-    if display_aspect == 0 then
+    if state.osd_dimensions.aspect == 0 then
         return
     end
     local display_h = 360
-    local display_w = display_h * display_aspect
+    local display_w = display_h * state.osd_dimensions.aspect
     -- logo is rendered at 2^(6-1) = 32 times resolution with size 1800x1800
     local icon_x, icon_y = (display_w - 1800 / 32) / 2, (display_h - 1800 / 32) / 2
     local line_prefix = ("{\\rDefault\\an7\\1a&H00&\\bord0\\shad0\\pos(%f,%f)}"):format(icon_x,
@@ -3185,8 +3185,8 @@ end
 mp.register_event("shutdown", shutdown)
 mp.register_event("start-file", request_init)
 mp.observe_property("track-list", "native", update_tracklist)
-mp.observe_property("playlist-count", "native", request_init)
-mp.observe_property("playlist-pos", "native", request_init)
+observe_cached("playlist-count", request_init)
+observe_cached("playlist-pos-1", request_init)
 observe_cached("chapter-list", function ()
     table.sort(state.chapter_list, function(a, b) return a.time < b.time end)
     update_duration_watch()
@@ -3249,18 +3249,14 @@ mp.add_hook("on_unload", 50, function()
 end)
 
 mp.observe_property("display-fps", "number", set_tick_delay)
-mp.observe_property("pause", "bool", request_tick)
-mp.observe_property("volume", "number", request_tick)
-mp.observe_property("mute", "bool", request_tick)
+observe_cached("pause", request_tick)
+observe_cached("volume", request_tick)
+observe_cached("mute", request_tick)
 observe_cached("demuxer-cache-state", request_tick)
 mp.observe_property("vo-configured", "bool", request_tick)
 mp.observe_property("playback-time", "number", request_tick)
-mp.observe_property("osd-dimensions", "native", function()
-    -- (we could use the value instead of re-querying it all the time, but then
-    --  we might have to worry about property update ordering)
-    request_init_resize()
-end)
-mp.observe_property('osd-scale-by-window', 'native', request_init_resize)
+observe_cached("osd-dimensions", request_init_resize)
+observe_cached("osd-scale-by-window", request_init_resize)
 mp.observe_property('touch-pos', 'native', handle_touch)
 
 -- mouse show/hide bindings