Add a button to change the tempo of the project without changing the positions of each note (in seconds)

OpenUtau/Strings/Strings.axaml

@@ -48,6 +48,10 @@
   <system:String x:Key="dialogs.messagebox.yes">Yes</system:String>
   <system:String x:Key="dialogs.noresampler.caption">No resampler</system:String>
   <system:String x:Key="dialogs.noresampler.message">No resampler! Put your favourite resampler exe or dll in the Resamplers folder and choose it in Preferences!</system:String>
+  <system:String x:Key="dialogs.remaptimeaxis.message">This tool will change the tempo of the project without changing the actual positions and durations (in seconds) of notes.
+  New BPM:</system:String>
+  <system:String x:Key="dialogs.unsupportedfile.caption">Unsupported file format</system:String>
+  <system:String x:Key="dialogs.unsupportedfile.message">Unsupported file format: </system:String>
   <system:String x:Key="dialogs.timesig.caption">Time Signature</system:String>
   <system:String x:Key="dialogs.tracksettings.caption">Track Settings</system:String>
   <system:String x:Key="dialogs.tracksettings.location">Location</system:String>
@@ -154,6 +158,9 @@
   <system:String x:Key="menu.help.logslocation">Open Logs Location</system:String>
   <system:String x:Key="menu.help.reportissue">Report Issue</system:String>
   <system:String x:Key="menu.help.wiki">OpenUtau Wiki</system:String>
+  <system:String x:Key="menu.project">Project</system:String>
+  <system:String x:Key="menu.project.expressions">Expressions...</system:String>
+  <system:String x:Key="menu.project.remaptimeaxis">Adjust Tempo (Preserve Timing)</system:String>
   <system:String x:Key="menu.tools">Tools</system:String>
   <system:String x:Key="menu.tools.clearcache">Clear Cache</system:String>
   <system:String x:Key="menu.tools.debugwindow">Debug Window</system:String>
@@ -166,7 +173,6 @@
   <system:String x:Key="menu.tools.layout.vsplit12">Vertical 1:2</system:String>
   <system:String x:Key="menu.tools.layout.vsplit13">Vertical 1:3</system:String>
   <system:String x:Key="menu.tools.prefs">Preferences...</system:String>
-  <system:String x:Key="menu.tools.project.expressions">Expressions...</system:String>
   <system:String x:Key="menu.tools.singer.install">Install Singer...</system:String>
   <system:String x:Key="menu.tools.singer.installadv">Install Singer (Advanced)...</system:String>
   <system:String x:Key="menu.tools.singers">Singers...</system:String>

OpenUtau/ViewModels/MainWindowViewModel.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using System.Reactive;
@@ -262,6 +263,60 @@ public void RefreshTimelineContextMenu(int tick) {
             }
         }
 
+        /// <summary>
+        /// Remap a tick position from the old time axis to the new time axis without changing its absolute position (in ms).
+        /// Note that this can only be used on positions, not durations.
+        /// </summary>
+        private int RemapTickPos(int tickPos, TimeAxis oldTimeAxis, TimeAxis newTimeAxis){
+            double msPos = oldTimeAxis.TickPosToMsPos(tickPos);
+            return newTimeAxis.MsPosToTickPos(msPos);
+        }
+
+        /// <summary>
+        /// Remap the starting and ending positions of all the notes and parts in the whole project 
+        /// from the old time axis to the new time axis, without changing their absolute positions in ms.
+        /// </summary>
+        public void RemapTimeAxis(TimeAxis oldTimeAxis, TimeAxis newTimeAxis){
+            var project = DocManager.Inst.Project;
+            foreach(var part in project.parts){
+                var partOldStartTick = part.position;
+                var partNewStartTick = RemapTickPos(part.position, oldTimeAxis, newTimeAxis);
+                if(partNewStartTick != partOldStartTick){
+                    DocManager.Inst.ExecuteCmd(new MovePartCommand(
+                        project, part, partNewStartTick, part.trackNo));
+                }
+                if(part is UVoicePart voicePart){
+                    var partOldEndTick = voicePart.End;
+                    var partNewEndTick = RemapTickPos(voicePart.End, oldTimeAxis, newTimeAxis);
+                    if(partNewEndTick - partNewStartTick != voicePart.Duration){
+                        DocManager.Inst.ExecuteCmd(new ResizePartCommand(
+                            project, voicePart, partNewEndTick - partNewStartTick));
+                    }
+                    var noteCommands = new List<UCommand>();
+                    foreach(var note in voicePart.notes){
+                        var noteOldStartTick = note.position + partOldStartTick;
+                        var noteOldEndTick = note.End + partOldStartTick;
+                        var noteOldDuration = note.duration;
+                        var noteNewStartTick = RemapTickPos(noteOldStartTick, oldTimeAxis, newTimeAxis);
+                        var noteNewEndTick = RemapTickPos(noteOldEndTick, oldTimeAxis, newTimeAxis);
+                        var deltaPosTickInPart = (noteNewStartTick - partNewStartTick) - (noteOldStartTick - partOldStartTick);
+                        if(deltaPosTickInPart != 0){
+                            noteCommands.Add(new MoveNoteCommand(voicePart, note, deltaPosTickInPart, 0));
+                        }
+                        var noteNewDuration = noteNewEndTick - noteNewStartTick;
+                        var deltaDur = noteNewDuration - noteOldDuration;
+                        if(deltaDur != 0){
+                            noteCommands.Add(new ResizeNoteCommand(voicePart, note, deltaDur));
+                        }
+                        //TODO: expression curve remapping, phoneme timing remapping
+                    }
+                    foreach(var command in noteCommands){
+                        DocManager.Inst.ExecuteCmd(command);
+                    }
+                }
+            }
+        }
+
         #region ICmdSubscriber
 
         public void OnNext(UCommand cmd, bool isUndo) {

OpenUtau/Views/MainWindow.axaml

@@ -67,6 +67,10 @@
             </MenuItem>
             <MenuItem Header="{DynamicResource menu.file.openexportlocation}" Click="OnMenuOpenProjectLocation"/>
           </MenuItem>
+          <MenuItem Header="{DynamicResource menu.project}">
+            <MenuItem Header="{DynamicResource menu.project.expressions}" Click="OnMenuExpressionss"/>
+            <MenuItem Header="{DynamicResource menu.project.remaptimeaxis}" Click="OnMenuRemapTimeaxis"/>
+          </MenuItem>
           <MenuItem Header="{DynamicResource menu.tools}">
             <MenuItem Header="{DynamicResource menu.tools.layout}">
               <MenuItem Header="{DynamicResource menu.tools.layout.vsplit11}" Click="OnMenuLayoutVSplit11"/>
@@ -79,7 +83,6 @@
             <MenuItem Header="{Binding ClearCacheHeader}" Click="OnMenuClearCache"/>
             <MenuItem Header="{DynamicResource menu.tools.debugwindow}" Click="OnMenuDebugWindow"/>
             <MenuItem Header="{DynamicResource phoneticassistant.caption}" Click="OnMenuPhoneticAssistant"/>
-            <MenuItem Header="{DynamicResource menu.tools.project.expressions}" Click="OnMenuExpressionss"/>
             <MenuItem Header="{DynamicResource menu.tools.singers}" Click="OnMenuSingers"/>
             <MenuItem Header="{DynamicResource menu.tools.singer.install}" Click="OnMenuInstallSinger"/>
             <MenuItem Header="{DynamicResource menu.tools.dependency.install}" Click="OnMenuInstallDependency"/>

OpenUtau/Views/MainWindow.axaml.cs

@@ -149,6 +149,38 @@ private void DelTempoChange(int tick) {
             DocManager.Inst.EndUndoGroup();
         }
 
+
+
+        void OnMenuRemapTimeaxis(object sender, RoutedEventArgs e){
+            var project = DocManager.Inst.Project;
+            var dialog = new TypeInDialog {
+                Title = ThemeManager.GetString("menu.project.remaptimeaxis")
+            };
+            dialog.Height = 200;
+            dialog.SetPrompt(ThemeManager.GetString("dialogs.remaptimeaxis.message"));
+            dialog.SetText(project.tempos[0].bpm.ToString());
+            dialog.onFinish = s => {
+                try{
+                    if (double.TryParse(s, out double bpm)) {
+                        DocManager.Inst.StartUndoGroup();
+                        var oldTimeAxis = project.timeAxis.Clone();
+                        DocManager.Inst.ExecuteCmd(new BpmCommand(
+                            project, bpm));
+                        foreach(var tempo in project.tempos.Skip(1)){
+                            DocManager.Inst.ExecuteCmd(new DelTempoChangeCommand(
+                                project, tempo.position));
+                        }
+                        viewModel.RemapTimeAxis(oldTimeAxis, project.timeAxis.Clone());
+                        DocManager.Inst.EndUndoGroup();
+                    }
+                } catch (Exception e) {
+                    Log.Error(e, "Failed to open project location.");
+                    MessageBox.ShowError(this, e);
+                }
+            };
+            dialog.ShowDialog(this);
+        }
+
         private void AddTimeSigChange(int bar) {
             var project = DocManager.Inst.Project;
             var timeSig = project.timeAxis.TimeSignatureAtBar(bar);

OpenUtau/Views/TypeInDialog.axaml

@@ -8,6 +8,7 @@
         Title="TypeInDialog" Height="120" Width="320" WindowStartupLocation="CenterOwner"
         ExtendClientAreaToDecorationsHint="False">
   <StackPanel VerticalAlignment="Center" Margin="{Binding $parent.WindowDecorationMargin}">
+    <TextBlock Margin="20" Name="Prompt" IsVisible="False" TextWrapping="Wrap" MaxWidth="560"/>
     <TextBox Name="TextBox" Margin="4"/>
     <Button Name="OkButton" Content="OK" Margin="4" HorizontalAlignment="Stretch"/>
   </StackPanel>

OpenUtau/Views/TypeInDialog.axaml.cs

@@ -12,6 +12,11 @@ public TypeInDialog() {
             OkButton.Click += OkButtonClick;
         }
 
+        public void SetPrompt(string prompt) {
+            Prompt.IsVisible = true;
+            Prompt.Text = prompt;
+        }
+
         public void SetText(string text) {
             TextBox.Text = text;
         }