songflow don't stop now during song scrolling and seems to be more "flowy"

hopefully the last hack to this old and dirty code, should be rewritten for 1.2
UScreenSongJumpTo may need some changes

git-svn-id: svn://svn.code.sf.net/p/ultrastardx/svn/trunk@2147 b956fd51-792f-4845-bead-9b4dfca2ff2c

1 files changed, 61 insertions, 47 deletions

diff --git a/src/screens/UScreenSong.pas b/src/screens/UScreenSong.pas
index 8c4c1608..b127c296 100644
--- a/src/screens/UScreenSong.pas
+++ b/src/screens/UScreenSong.pas
@@ -60,6 +60,8 @@ type
       PreviewOpened: Integer; // interaction of the Song that is loaded for preview music
                               // -1 if nothing is opened
 
+      isScrolling: boolean;   // true if song flow is about to move
+
       procedure StartMusicPreview();
       procedure StopMusicPreview();
     public
@@ -148,6 +150,9 @@ type
       procedure DoJoker(Team: integer);
       procedure SelectPlayers;
 
+      procedure OnSongSelect;   // called when song flows movement stops at a song
+      procedure OnSongDeSelect; // called before current song is deselected
+
       procedure UnloadDetailedCover;
 
       //Extensions
@@ -299,7 +304,6 @@ begin
 
                 AudioPlayback.PlaySound(SoundLib.Change);
 
-                ChangeMusic;
                 SetScroll4;
                 //Break and Exit
                 Exit;
@@ -322,7 +326,6 @@ begin
 
                 AudioPlayback.PlaySound(SoundLib.Change);
 
-                ChangeMusic;
                 SetScroll4;
 
                 //Break and Exit
@@ -476,7 +479,6 @@ begin
             end;
             AudioPlayback.PlaySound(SoundLib.Change);
 
-            ChangeMusic;
             SetScroll4;
           end;
           Exit;
@@ -536,8 +538,6 @@ begin
                 //Show Wrong Song when Tabs on Fix
                 SelectNext(true);
                 FixSelected;
-
-                ChangeMusic;
               end
               else
               begin
@@ -576,9 +576,6 @@ begin
               //Show Wrong Song when Tabs on Fix
               SelectNext(true);
               FixSelected;
-
-              //Play Music:
-              ChangeMusic;
             end
             else
             begin // clicked on song
@@ -639,8 +636,6 @@ begin
 
                 //Play Music:
                 AudioPlayback.PlaySound(SoundLib.Change);
-                ChangeMusic;
-
               end;
 
             //
@@ -683,7 +678,6 @@ begin
 
                 //Play Music:
                 AudioPlayback.PlaySound(SoundLib.Change);
-                ChangeMusic;
               end;
             end;
             //Cat Change Hack End}
@@ -696,9 +690,6 @@ begin
           begin
             AudioPlayback.PlaySound(SoundLib.Change);
             SelectNext(true);
-            //InteractNext;
-            //SongTarget := Interaction;
-            ChangeMusic;
             SetScroll4;
           end;
         end;
@@ -709,7 +700,6 @@ begin
           begin
             AudioPlayback.PlaySound(SoundLib.Change);
             SelectPrev(true);
-            ChangeMusic;
             SetScroll4;
           end;
         end;
@@ -889,6 +879,7 @@ begin
   Equalizer := Tms_Equalizer.Create(AudioPlayback, Theme.Song.Equalizer);
 
   PreviewOpened := -1;
+  isScrolling := false;
 end;
 
 procedure TScreenSong.GenerateThumbnails();
@@ -957,6 +948,28 @@ begin
     Interaction := 0;
 end;
 
+{ called when song flows movement stops at a song }
+procedure TScreenSong.OnSongSelect;
+begin
+  if (Ini.PreviewVolume <> 0) then
+  begin
+    StartMusicPreview;
+  end;
+
+  // fade in detailed cover
+  CoverTime := 0;
+end;
+
+{ called before current song is deselected }
+procedure TScreenSong.OnSongDeSelect;
+begin
+  CoverTime := 10;
+  UnLoadDetailedCover;
+
+  StopMusicPreview();
+  PreviewOpened := -1;
+end;
+
 procedure TScreenSong.SetScroll;
 var
   VS, B: integer;
@@ -1474,6 +1487,7 @@ begin
   SoundLib.PauseBgMusic;
 
   AudioPlayback.Stop;
+  PreviewOpened := -1;
 
   if Ini.Players <= 3 then PlayersPlay := Ini.Players + 1;
   if Ini.Players  = 4 then PlayersPlay := 6;
@@ -1489,12 +1503,6 @@ begin
 
   if Length(CatSongs.Song) > 0 then
   begin
-    //Load Music only when Song Preview is activated
-    if ( Ini.PreviewVolume <> 0 ) then
-      StartMusicPreview()
-    else
-      PreviewOpened := -1;
-
     SetScroll;
   end;
 
@@ -1505,7 +1513,6 @@ begin
     if (CatSongs.CatNumShow = -3) then
     begin
       SelectNext(true);
-      ChangeMusic;
     end;
   end
   //Party Mode
@@ -1520,6 +1527,7 @@ begin
     end;
   end;
 
+  isScrolling := true;
   SetJoker;
   SetStatics;
 end;
@@ -1560,13 +1568,23 @@ var
   dt: real;
   I:  integer;
 begin
-  dx := SongTarget-SongCurrent;
-  dt := TimeSkip * 7;
+  if isScrolling then
+  begin
+    dx := SongTarget-SongCurrent;
+    dt := TimeSkip * 7;
 
-  if dt > 1 then
-    dt := 1;
-    
-  SongCurrent := SongCurrent + dx*dt;
+    if dt > 1 then
+      dt := 1;
+
+    SongCurrent := SongCurrent + dx*dt;
+
+    if SameValue(SongCurrent, SongTarget, 0.002) and (CatSongs.VisibleSongs > 0) then
+    begin
+      isScrolling := false;
+      SongCurrent := SongTarget;
+      OnSongSelect;
+    end;
+  end;
 
   {
   if SongCurrent > Catsongs.VisibleSongs then
@@ -1643,8 +1661,11 @@ begin
 
   if VS > 0 then
   begin
-    if UnloadCover then      //that should fix the performance problem on scrolling
-      UnLoadDetailedCover;
+    if (not isScrolling) and (VS > 1) then
+    begin
+      isScrolling := true;
+      OnSongDeselect;
+    end;
 
     Skip := 1;
 
@@ -1677,10 +1698,13 @@ var
 begin
   VS := CatSongs.VisibleSongs;
 
-  if VS > 0 then
+  if VS > 1 then
   begin
-    if UnloadCover then
-      UnLoadDetailedCover;    //that should fix the performance problem on scrolling
+    if (not isScrolling) and (VS > 1) then
+    begin
+      isScrolling := true;
+      OnSongDeselect;
+    end;
 
     Skip := 1;
 
@@ -1708,6 +1732,9 @@ var
 begin
   AudioPlayback.Close();
 
+  if CatSongs.VisibleSongs = 0 then
+    Exit;
+    
   Song := CatSongs.Song[Interaction];
   if not assigned(Song) then
     Exit;
@@ -1768,23 +1795,13 @@ procedure TScreenSong.ChangeMusic;
 begin
   StopMusicPreview();
   PreviewOpened := -1;
-
-  // Preview song if activated and current selection is not a category cover
-  if (CatSongs.VisibleSongs > 0) and
-     (not CatSongs.Song[Interaction].Main) and
-     (Ini.PreviewVolume <> 0) then
-  begin
-    // Delay song fading to prevent the song from being played while scrolling
-    MusicPreviewTimer := SDL_AddTimer(200, MusicPreviewTimerCallback, Self);
-  end;
+  StartMusicPreview();
 end;
 
 procedure TScreenSong.SkipTo(Target: cardinal);
 var
   i: integer;
 begin
-  UnLoadDetailedCover;
-
   Interaction := High(CatSongs.Song);
   SongTarget  := 0;
 
@@ -1853,7 +1870,6 @@ begin
   end;
 
   AudioPlayback.PlaySound(SoundLib.Change);
-  ChangeMusic;
   SetScroll;
 end;
 
@@ -2016,8 +2032,6 @@ end;
 //Detailed Cover Unloading. Unloads the Detailed, uncached Cover of the cur. Song
 procedure TScreenSong.UnloadDetailedCover;
 begin
-  CoverTime := 0;
-
   // show cached texture
   Button[Interaction].Texture := Texture.GetTexture(Button[Interaction].Texture.Name, TEXTURE_TYPE_PLAIN, true);
   Button[Interaction].Texture2.Alpha := 0;