Fixed locked-in, fixed aspect ratio

Author: angeldeejay

obs-zoom-to-mouse.lua

@@ -51,8 +51,6 @@ local osx_mouse_location = nil
 local use_auto_follow_mouse = true
 local use_follow_outside_bounds = false
 local is_following_mouse = false
-local force_16_9 = true
-local lock_in = false
 local follow_speed = 0.1
 local follow_border = 0
 local follow_safezone_sensitivity = 10
@@ -89,7 +87,11 @@ local m1, m2 = version:match("(%d+%.%d+)%.(%d+)")
 local major = tonumber(m1) or 0
 local minor = tonumber(m2) or 0
 
-local __ar16_9__ = 16 / 9
+local keep_shape = false
+local auto_start = false
+local auto_start_running = false
+local aspect_ratio_w = 1
+local aspect_ratio_h = 1
 
 -- Define the mouse cursor functions for each platform
 if ffi.os == "Windows" then
@@ -300,6 +302,33 @@ function clamp(min, max, value)
     return math.max(min, math.min(max, value))
 end
 
+---
+-- Function to calculate GCD (Greatest Common Divisor)
+--- @param a number
+--- @param b number
+function gcd(a, b)
+    while b ~= 0 do
+        local temp = b
+        b = a % b
+        a = temp
+    end
+    return a
+end
+
+---
+-- Function to convert resolution to aspect ratio
+--- @param width number the width of the resolution
+--- @param height number the height of the resolution
+--- @return number aspect_width, number aspect_height the simplified aspect ratio as two numbers
+function resolution_to_aspect_ratio(width, height)
+    -- Calculate GCD of width and height
+    local divisor = gcd(width, height)
+    -- Simplify width and height using GCD
+    local aspect_width = width / divisor
+    local aspect_height = height / divisor
+    return aspect_width, aspect_height
+end
+
 ---
 -- Get the size and position of the monitor so that we know the top-left mouse point
 ---@param source any The OBS source
@@ -462,6 +491,7 @@ function release_sceneitem()
             sceneitem_crop_orig = nil
         end
 
+        toggle_sceneitem_change_listener(false)
         obs.obs_sceneitem_release(sceneitem)
         sceneitem = nil
     end
@@ -545,13 +575,15 @@ function refresh_sceneitem(find_newest)
                     -- We start at the current scene and use a BFS to look into any nested scenes
                     local current = obs.obs_scene_from_source(scene_source)
                     sceneitem = find_scene_item_by_name(current)
+                    toggle_sceneitem_change_listener(true)
 
                     obs.obs_source_release(scene_source)
                 end
 
                 if not sceneitem then
                     log("WARNING: Source not part of the current scene hierarchy.\n" ..
                         "         Try selecting a different zoom source or switching scenes.")
+                    toggle_sceneitem_change_listener(false)
                     obs.obs_sceneitem_release(sceneitem)
                     obs.obs_source_release(source)
 
@@ -788,8 +820,12 @@ function get_target_position(zoom)
     -- Remember that because we are using a crop/pad filter making the size smaller (dividing by zoom) means that we see less of the image
     -- in the same amount of space making it look bigger (aka zoomed in)
     local new_size = {
-        -- if aspect ratio should be fixed to 16:9, compute width from height instead of getting directly from display size
-        width = (force_16_9 and (zoom.source_size.height * __ar16_9__) or zoom.source_size.width) / zoom.zoom_to,
+        width = (
+            --  if should keep shape, use aspect ratio to get new width
+            keep_shape and (zoom.source_size.height * (aspect_ratio_w / aspect_ratio_h))
+            --  else use source resolution
+            or  zoom.source_size.width
+        ) / zoom.zoom_to,
         height = zoom.source_size.height / zoom.zoom_to
     }
 
@@ -831,26 +867,11 @@ function on_toggle_follow(pressed)
 end
 
 function on_toggle_zoom(pressed, force_value)
-    if force_value or pressed then
+    if pressed or force_value then
         -- Check if we are in a safe state to zoom
-        if force_value or zoom_state == ZoomState.ZoomedIn or zoom_state == ZoomState.None then
-            local should_zoom
-            if force_value == nil then
-                should_zoom = zoom_state == ZoomState.ZoomedIn or zoom_state == ZoomState.None
-            else
-                should_zoom = force_value
-            end
-
-            if should_zoom then
-                log("Zooming in")
-                -- To zoom in, we get a new target based on where the mouse was when zoom was clicked
-                zoom_state = ZoomState.ZoomingIn
-                zoom_info.zoom_to = zoom_value
-                zoom_time = 0
-                locked_center = nil
-                locked_last_pos = nil
-                zoom_target = get_target_position(zoom_info)
-            else
+        if zoom_state == ZoomState.ZoomedIn or zoom_state == ZoomState.None or force_value then
+            local should_zoom = (force_value ~= nil) and force_value or (zoom_state ~= ZoomState.ZoomedIn)
+            if not should_zoom then
                 log("Zooming out")
                 -- To zoom out, we set the target back to whatever it was originally
                 zoom_state = ZoomState.ZoomingOut
@@ -862,6 +883,18 @@ function on_toggle_zoom(pressed, force_value)
                     is_following_mouse = false
                     log("Tracking mouse is off (due to zoom out)")
                 end
+            else
+                log("Zooming in")
+                -- To zoom in, we get a new target based on where the mouse was when zoom was clicked
+                if keep_shape then
+                    update_aspect_ratio()
+                end
+                zoom_state = ZoomState.ZoomingIn
+                zoom_info.zoom_to = zoom_value
+                zoom_time = 0
+                locked_center = nil
+                locked_last_pos = nil
+                zoom_target = get_target_position(zoom_info)
             end
 
             -- Since we are zooming we need to start the timer for the animation and tracking
@@ -1083,6 +1116,43 @@ function on_transition_start(t)
     release_sceneitem()
 end
 
+function update_aspect_ratio()
+    if keep_shape == nil or not keep_shape or sceneitem == nil then
+        return
+    end
+
+    sceneitem_info_current = obs.obs_transform_info()
+    obs.obs_sceneitem_get_info(sceneitem, sceneitem_info_current)
+    aspect_ratio_w, aspect_ratio_h = resolution_to_aspect_ratio(
+        sceneitem_info_current.bounds.x, sceneitem_info_current.bounds.y
+    )
+end
+
+function on_transform_update()
+    update_aspect_ratio()
+    if keep_shape then
+        if zoom_state == ZoomState.ZoomedIn then
+            -- Perform zoom again
+            zoom_state = ZoomState.ZoomingIn
+            zoom_info.zoom_to = zoom_value
+            zoom_time = 0
+            zoom_target = get_target_position(zoom_info)
+        end
+    end
+end
+
+function toggle_sceneitem_change_listener(value)
+    local scene = obs.obs_sceneitem_get_scene(sceneitem)
+    local scene_source = obs.obs_scene_get_source(scene)
+    local handler = obs.obs_source_get_signal_handler(scene_source)
+    if value then
+        update_aspect_ratio()
+        obs.signal_handler_connect(handler, "item_transform", on_transform_update)
+    else
+        obs.signal_handler_disconnect(handler, on_transform_update)
+    end
+end
+
 function on_frontend_event(event)
     if event == obs.OBS_FRONTEND_EVENT_SCENE_CHANGED then
         log("OBS Scene changed")
@@ -1142,15 +1212,14 @@ function on_settings_modified(props, prop, settings)
         local sources_list = obs.obs_properties_get(props, "source")
         populate_zoom_sources(sources_list)
         return true
+    elseif name == "keep_shape" then
+        on_transform_update()
     elseif name == "debug_logs" then
         if obs.obs_data_get_bool(settings, "debug_logs") then
             log_current_settings()
         end
     end
 
-    if lock_in ~= nil then
-        on_toggle_zoom(true, lock_in)
-    end
     return false
 end
 
@@ -1160,6 +1229,8 @@ function log_current_settings()
     local settings = {
         zoom_value = zoom_value,
         zoom_speed = zoom_speed,
+        auto_start = auto_start,
+        keep_shape = keep_shape,
         use_auto_follow_mouse = use_auto_follow_mouse,
         use_follow_outside_bounds = use_follow_outside_bounds,
         follow_speed = follow_speed,
@@ -1179,8 +1250,6 @@ function log_current_settings()
         socket_port = socket_port,
         socket_poll = socket_poll,
         debug_logs = debug_logs,
-        force_16_9 = force_16_9,
-        lock_in = lock_in,
         version = VERSION
     }
 
@@ -1199,8 +1268,9 @@ function on_print_help()
         "Zoom Source: The display capture in the current scene to use for zooming\n" ..
         "Zoom Factor: How much to zoom in by\n" ..
         "Zoom Speed: The speed of the zoom in/out animation\n" ..
+        "Zoomed at OBS startup: Start OBS with source zoomed\n" ..
+        "Dynamic Aspect Ratio: Adjusst zoom aspect ratio to canvas source size\n" ..
         "Auto follow mouse: True to track the cursor while you are zoomed in\n" ..
-        "Force 16:9: True to get zoomed window as 16:9 (fixes problems with wide resolutions)\n" ..
         "Follow outside bounds: True to track the cursor even when it is outside the bounds of the source\n" ..
         "Follow Speed: The speed at which the zoomed area will follow the mouse when tracking\n" ..
         "Follow Border: The %distance from the edge of the source that will re-enable mouse tracking\n" ..
@@ -1256,10 +1326,15 @@ function script_properties()
     -- Add the rest of the settings UI
     local zoom = obs.obs_properties_add_float(props, "zoom_value", "Zoom Factor", 1, 5, 0.5)
     local zoom_speed = obs.obs_properties_add_float_slider(props, "zoom_speed", "Zoom Speed", 0.01, 1, 0.01)
-    local lock_in = obs.obs_properties_add_bool(props, "lock_in", "Lock-In ")
-    obs.obs_property_set_long_description(lock_in,
-        "When enabled, auto zoom feature cannot be disabled manually, and auto zoom restarts with OBS too")
-    local force_16_9 = obs.obs_properties_add_bool(props, "force_16_9", "Force 16:9 aspect ratio ")
+
+    local auto_start = obs.obs_properties_add_bool(props, "auto_start", "Zoomed at OBS startup ")
+    obs.obs_property_set_long_description(auto_start,
+        "When enabled, auto zoom is activated on OBS start up as soon as possible")
+
+    local keep_shape = obs.obs_properties_add_bool(props, "keep_shape", "Dynamic Aspect Ratio ")
+    obs.obs_property_set_long_description(keep_shape,
+        "When enabled, zoom will follow he aspect ratio of source in canvas")
+
     local follow = obs.obs_properties_add_bool(props, "follow", "Auto follow mouse ")
     obs.obs_property_set_long_description(follow,
         "When enabled mouse traking will auto-start when zoomed in without waiting for tracking toggle hotkey")
@@ -1375,7 +1450,6 @@ function script_load(settings)
     -- Load any other settings
     zoom_value = obs.obs_data_get_double(settings, "zoom_value")
     zoom_speed = obs.obs_data_get_double(settings, "zoom_speed")
-    use_auto_follow_mouse = obs.obs_data_get_bool(settings, "follow")
     use_follow_outside_bounds = obs.obs_data_get_bool(settings, "follow_outside_bounds")
     follow_speed = obs.obs_data_get_double(settings, "follow_speed")
     follow_border = obs.obs_data_get_int(settings, "follow_border")
@@ -1395,8 +1469,8 @@ function script_load(settings)
     socket_port = obs.obs_data_get_int(settings, "socket_port")
     socket_poll = obs.obs_data_get_int(settings, "socket_poll")
     debug_logs = obs.obs_data_get_bool(settings, "debug_logs")
-    lock_in = obs.obs_data_get_bool(settings, "lock_in")
-    force_16_9 = obs.obs_data_get_bool(settings, "force_16_9")
+    auto_start = obs.obs_data_get_bool(settings, "auto_start")
+    keep_shape = obs.obs_data_get_bool(settings, "keep_shape")
 
     obs.obs_frontend_add_event_callback(on_frontend_event)
 
@@ -1424,6 +1498,13 @@ function script_load(settings)
     source_name = ""
     use_socket = false
     is_script_loaded = true
+
+    if source_name ~= "obs-zoom-to-mouse-none" and auto_start and not auto_start_running then
+        log("Auto starting")
+        auto_start_running = true
+        local timer_interval = math.floor(obs.obs_get_frame_interval_ns() / 100000)
+        obs.timer_add(wait_for_auto_start, timer_interval)
+    end
 end
 
 function script_unload()
@@ -1455,10 +1536,6 @@ function script_unload()
     if socket_server ~= nil then
         stop_server()
     end
-
-    if lock_in then
-        on_toggle_zoom(true, false)
-    end
 end
 
 function script_defaults(settings)
@@ -1485,8 +1562,8 @@ function script_defaults(settings)
     obs.obs_data_set_default_int(settings, "socket_port", 12345)
     obs.obs_data_set_default_int(settings, "socket_poll", 10)
     obs.obs_data_set_default_bool(settings, "debug_logs", false)
-    obs.obs_data_set_default_bool(settings, "force_16_9", true)
-    obs.obs_data_set_default_bool(settings, "lock_in", false)
+    obs.obs_data_set_default_bool(settings, "auto_start", false)
+    obs.obs_data_set_default_bool(settings, "keep_shape", false)
 end
 
 function script_save(settings)
@@ -1543,8 +1620,8 @@ function script_update(settings)
     socket_port = obs.obs_data_get_int(settings, "socket_port")
     socket_poll = obs.obs_data_get_int(settings, "socket_poll")
     debug_logs = obs.obs_data_get_bool(settings, "debug_logs")
-    force_16_9 = obs.obs_data_get_bool(settings, "force_16_9")
-    lock_in = obs.obs_data_get_bool(settings, "lock_in")
+    auto_start = obs.obs_data_get_bool(settings, "auto_start")
+    keep_shape = obs.obs_data_get_bool(settings, "keep_shape")
 
     -- Only do the expensive refresh if the user selected a new source
     if source_name ~= old_source_name and is_obs_loaded then
@@ -1578,20 +1655,30 @@ function script_update(settings)
         start_server()
     end
 
-    if lock_in ~= nil and source == nil then
+    if source_name ~= "obs-zoom-to-mouse-none" and auto_start and not auto_start_running then
+        log("Auto starting")
+        auto_start_running = true
         local timer_interval = math.floor(obs.obs_get_frame_interval_ns() / 100000)
         obs.timer_add(wait_for_auto_start, timer_interval)
-    elseif lock_in ~= nil and source ~= nil then
-        on_toggle_zoom(true, lock_in)
     end
 end
 
 function wait_for_auto_start()
-    local found_source = obs.obs_get_source_by_name(source_name)
-    if found_source ~= nil then
-        source = found_source
-        on_toggle_zoom(true, lock_in)
+    if source_name == "obs-zoom-to-mouse-none" or not auto_start then
         obs.remove_current_callback()
+        auto_start_running = false
+        log("Auto start cancelled")
+    else
+        auto_start_running = true
+        local found_source = obs.obs_get_source_by_name(source_name)
+        if found_source ~= nil then
+            -- zoom_state = ZoomState.ZoomingIn
+            source = found_source
+            on_toggle_zoom(true, true)
+            obs.remove_current_callback()
+            auto_start_running = false
+            log("Auto start done")
+        end
     end
 end