4PointCutting: Make SWS extension neccessary for script. Abort if not present.

4PointCutting/4Pcut_execute.lua

@@ -129,6 +129,9 @@ elseif (edit_mode == 1 or edit_mode == 2 or edit_mode == 5) and (mark_srcin_pos
 elseif (edit_mode == 3 or edit_mode == 4 or edit_mode == 5) and (mark_dstin_pos >= mark_dstout_pos) then
     msg('DST-IN Marker must be set left of DST-OUT marker! Aborting.')
     return
+elseif not sws_present then
+    msg('SWS extensions are not installed but needed! Aborting.')
+    return
 end
 
 -- Do stuff before actual edits...
@@ -178,22 +181,21 @@ reaper.GoToMarker(0, mark_dstin_id, false)
 select_dst_track_only()
 --reaper.Main_OnCommand(40058, 0) -- paste item 
 reaper.Main_OnCommand( reaper.NamedCommandLookup('_SWS_AWPASTE'), 0 ) -- SWS Paste
--- Crossfade (only with SWS extensions, "fill gaps")
-if sws_present then
-    -- select track with selected items
-    local selected_items_count = reaper.CountSelectedMediaItems(0)
-    for i = 0, selected_items_count - 1  do
-        local item = reaper.GetSelectedMediaItem(0, i)
-        local track = reaper.GetMediaItem_Track(item)
-        reaper.SetTrackSelected(track, true)   
-    end
-    reaper.Main_OnCommand( 40290, 0 ) -- set time selection to selected items 
-    reaper.Main_OnCommand( 40320, 0 ) -- nudge left edge of time selection left
-    reaper.Main_OnCommand( 40323, 0 ) -- nudge right edge of time selection right
-    reaper.Main_OnCommand( 40718, 0 ) -- select items on selected tracks and in time selection
-    reaper.Main_OnCommand( reaper.NamedCommandLookup('_SWS_CROSSFADE'), 0 )  --  fill gaps between selected items and crossfade
+
+-- Crossfade
+local selected_items_count = reaper.CountSelectedMediaItems(0)
+for i = 0, selected_items_count - 1  do -- select tracks with selected items...
+    local item = reaper.GetSelectedMediaItem(0, i)
+    local track = reaper.GetMediaItem_Track(item)
+    reaper.SetTrackSelected(track, true)   
 end
-    -- Move dstin marker according to edit mode
+reaper.Main_OnCommand( 40290, 0 ) -- set time selection to selected items 
+reaper.Main_OnCommand( 40320, 0 ) -- nudge left edge of time selection left
+reaper.Main_OnCommand( 40323, 0 ) -- nudge right edge of time selection right
+reaper.Main_OnCommand( 40718, 0 ) -- select items on selected tracks and in time selection
+reaper.Main_OnCommand( reaper.NamedCommandLookup('_SWS_CROSSFADE'), 0 )  --  Crossfade adjacent selected items
+
+-- Move dstin marker according to edit mode
 if edit_mode == 1 then 
     reaper.SetProjectMarker(mark_dstin_id, false, mark_dstin_pos + (mark_srcout_pos - mark_srcin_pos), 0, 'DST-IN_4Pcut')
 elseif edit_mode == 2 then