File > Export > Animation: overhaul completely

Relates to #513 .  Thank you to @hi5 for their thoughtful discussion on how to improve PD's Export menu.

PD's various `File > Export > Animated GIF/JPEG-XL/PNG/WebP` menus are now merged into a single Export > Animation menu.  This menu launches a standard Save dialog where you can choose between those formats, and the dialog has the same auto-detect-format behavior if you manually type in a file extension.

This change was more cumbersome than I expected.  To ensure smooth workflows, PhotoDemon needs to remember export details for a given image (so that, for example, if you load an animated GIF and export it to an animated WebP, when you return to the Export dialog it needs to auto-suggest WebP as the format - not GIF).  It also needs to choose intelligent defaults when it can.  These little nuances add up and lead to a lot of extra code.

Next up: writing a new `Export > Image to file` menu that allows you to export the active image to arbitrary new formats (without modifying image save state).

Forms/MainWindow.frm

@@ -150,19 +150,19 @@ Begin VB.Form FormMain
          Caption         =   "Export"
          Index           =   12
          Begin VB.Menu MnuFileExport 
-            Caption         =   "Animated GIF..."
+            Caption         =   "Image to file..."
             Index           =   0
          End
          Begin VB.Menu MnuFileExport 
-            Caption         =   "Animated JPEG XL..."
+            Caption         =   "Layers to files..."
             Index           =   1
          End
          Begin VB.Menu MnuFileExport 
-            Caption         =   "Animated PNG..."
+            Caption         =   "-"
             Index           =   2
          End
          Begin VB.Menu MnuFileExport 
-            Caption         =   "Animated WebP..."
+            Caption         =   "Animation..."
             Index           =   3
          End
          Begin VB.Menu MnuFileExport 
@@ -3089,13 +3089,13 @@ End Sub
 Private Sub MnuFileExport_Click(Index As Integer)
     Select Case Index
         Case 0
-            Actions.LaunchAction_ByName "file_export_animatedgif"
+            Actions.LaunchAction_ByName "file_export_image"
         Case 1
-            Actions.LaunchAction_ByName "file_export_animatedjxl"
+            Actions.LaunchAction_ByName "file_export_layers"
         Case 2
-            Actions.LaunchAction_ByName "file_export_animatedpng"
+            '(separator)
         Case 3
-            Actions.LaunchAction_ByName "file_export_animatedwebp"
+            Actions.LaunchAction_ByName "file_export_animation"
         Case 4
             '(separator)
         Case 5

Modules/Actions.bas

@@ -233,21 +233,17 @@ Private Function Launch_ByName_MenuFile(ByRef srcMenuName As String, Optional By
             Process "Revert", False, , UNDO_Everything
 
         Case "file_export"
-            Case "file_export_animatedgif"
+            Case "file_export_image"
                 If (Not PDImages.IsImageActive()) Then Exit Function
-                Process "Export animated GIF", True
+                Process "Export image", True
 
-            Case "file_export_animatedjxl"
+            Case "file_export_layers"
                 If (Not PDImages.IsImageActive()) Then Exit Function
-                Process "Export animated JPEG XL", True
+                Process "Export layers", True
 
-            Case "file_export_animatedpng"
+            Case "file_export_animation"
                 If (Not PDImages.IsImageActive()) Then Exit Function
-                Process "Export animated PNG", True
-
-            Case "file_export_animatedwebp"
-                If (Not PDImages.IsImageActive()) Then Exit Function
-                Process "Export animated WebP", True
+                Process "Export animation", True
 
             Case "file_export_colorlookup"
                 If (Not PDImages.IsImageActive()) Then Exit Function

Modules/Menus.bas

@@ -177,10 +177,10 @@ Public Sub InitializeMenus()
     AddMenuItem "Save as...", "file_saveas", 0, 10, , "file_saveas"
     AddMenuItem "Revert", "file_revert", 0, 11
     AddMenuItem "Export", "file_export", 0, 12
-        AddMenuItem "Animated GIF...", "file_export_animatedgif", 0, 12, 0
-        AddMenuItem "Animated JPEG XL...", "file_export_animatedjxl", 0, 12, 1
-        AddMenuItem "Animated PNG...", "file_export_animatedpng", 0, 12, 2
-        AddMenuItem "Animated WebP...", "file_export_animatedwebp", 0, 12, 3
+        AddMenuItem "Image to file...", "file_export_image", 0, 12, 0
+        AddMenuItem "Layers to files...", "file_export_layers", 0, 12, 1
+        AddMenuItem "-", "-", 0, 12, 2
+        AddMenuItem "Animation...", "file_export_animation", 0, 12, 3
         AddMenuItem "-", "-", 0, 12, 4
         AddMenuItem "Color lookup...", "file_export_colorlookup", 0, 12, 5
         AddMenuItem "Color profile...", "file_export_colorprofile", 0, 12, 6

Modules/Processor.bas

@@ -1396,20 +1396,19 @@ Private Function Process_FileMenu(ByVal processID As String, Optional raiseDialo
         End If
         Process_FileMenu = True
 
-    ElseIf Strings.StringsEqual(processID, "Export animated GIF", True) Then
-        Saving.Export_Animation PDIF_GIF, PDImages.GetActiveImage()
+    ElseIf Strings.StringsEqual(processID, "Export image", True) Then
+        'TODO:
+        'Saving.Export_Animation PDIF_GIF, PDImages.GetActiveImage()
         Process_FileMenu = True
 
-    ElseIf Strings.StringsEqual(processID, "Export animated JPEG XL", True) Then
-        Saving.Export_Animation PDIF_JXL, PDImages.GetActiveImage()
+    ElseIf Strings.StringsEqual(processID, "Export layers", True) Then
+        'TODO:
+        'Saving.Export_Animation PDIF_JXL, PDImages.GetActiveImage()
         Process_FileMenu = True
 
-    ElseIf Strings.StringsEqual(processID, "Export animated PNG", True) Then
-        Saving.Export_Animation PDIF_PNG, PDImages.GetActiveImage()
-        Process_FileMenu = True
-
-    ElseIf Strings.StringsEqual(processID, "Export animated WebP", True) Then
-        Saving.Export_Animation PDIF_WEBP, PDImages.GetActiveImage()
+    ElseIf Strings.StringsEqual(processID, "Export animation", True) Then
+        'TODO:
+        Saving.Export_Animation PDImages.GetActiveImage()
         Process_FileMenu = True
 
     ElseIf Strings.StringsEqual(processID, "Export color lookup", True) Then