From 9eb4a1dc89898024bbd0721fdbf59f4151c71a4c Mon Sep 17 00:00:00 2001
From: Johannes Sixt <johannes.sixt@telecom.at>
Date: Thu, 11 Aug 2005 19:27:00 +0000
Subject: [PATCH] r616: The UndoStackItem::redo() is dropped and replaced by
 UndoStackItem::undo(). The latter must reverse its state so that the next
 invocation does a redo.

---
 cinelerra/mainundo.C      | 26 ++++++++------------------
 cinelerra/mwindowedit.C   | 26 ++++++++------------------
 cinelerra/undostackitem.C |  4 ----
 cinelerra/undostackitem.h | 11 ++++++-----
 4 files changed, 22 insertions(+), 45 deletions(-)

diff --git a/cinelerra/mainundo.C b/cinelerra/mainundo.C
index 42ac6b35..dc504dd3 100644
--- a/cinelerra/mainundo.C
+++ b/cinelerra/mainundo.C
@@ -20,13 +20,12 @@
 class MainUndoStackItem : public UndoStackItem
 {
 public:
-	MainUndoStackItem(MainUndo* main_undo, char* description,
+	MainUndoStackItem(MainUndo* undo, char* description,
 			uint32_t load_flags);
 	virtual ~MainUndoStackItem();
 
 	void set_data_before(char *data);
 	virtual void undo();
-	virtual void redo();
 	virtual int get_size();
 
 private:
@@ -118,22 +117,20 @@ void MainUndo::update_undo_after()
 
 int MainUndo::undo()
 {
-	if(undo_stack.last)
-	{
-		UndoStackItem* current_entry = undo_stack.last;
+	UndoStackItem* current_entry = undo_stack.last;
 
+	if(current_entry)
+	{
 // move item to redo_stack
 		undo_stack.remove_pointer(current_entry);
+		current_entry->undo();
 		redo_stack.append(current_entry);
-
-		if(current_entry->description && mwindow->gui) 
-			mwindow->gui->mainmenu->redo->update_caption(current_entry->description);
-
-      current_entry->undo();
 		capture_state();
 
 		if(mwindow->gui)
 		{
+			mwindow->gui->mainmenu->redo->update_caption(current_entry->description);
+
 			if(undo_stack.last)
 				mwindow->gui->mainmenu->undo->update_caption(undo_stack.last->description);
 			else
@@ -149,12 +146,10 @@ int MainUndo::redo()
 	
 	if(current_entry)
 	{
-
 // move item to undo_stack
 		redo_stack.remove_pointer(current_entry);
+		current_entry->undo();
 		undo_stack.append(current_entry);
-
-      current_entry->redo();
 		capture_state();
 
 		if(mwindow->gui)
@@ -232,11 +227,6 @@ void MainUndoStackItem::undo()
 	load_from_undo(&file, load_flags);
 }
 
-void MainUndoStackItem::redo()
-{
-	undo();
-}
-
 int MainUndoStackItem::get_size()
 {
 	return data_before ? strlen(data_before) : 0;
diff --git a/cinelerra/mwindowedit.C b/cinelerra/mwindowedit.C
index 062c5a1d..279d1690 100644
--- a/cinelerra/mwindowedit.C
+++ b/cinelerra/mwindowedit.C
@@ -1652,7 +1652,6 @@ class InPointUndoItem : public UndoStackItem
 public:
 	InPointUndoItem(double old_position, double new_position, EDL *edl);
 	void undo();
-	void redo();
 	int get_size();
 private:
 	double old_position;
@@ -1672,11 +1671,10 @@ InPointUndoItem::InPointUndoItem(
 void InPointUndoItem::undo()
 {
    edl->set_inpoint(old_position);
-}
-
-void InPointUndoItem::redo()
-{
-   edl->set_inpoint(new_position);
+// prepare to undo the undo
+	double tmp = new_position;
+	new_position = old_position;
+	old_position = tmp;
 }
 
 int InPointUndoItem::get_size()
@@ -1723,7 +1721,6 @@ class OutPointUndoItem : public UndoStackItem
 public:
 	OutPointUndoItem(double old_position, double new_position, EDL *edl);
 	void undo();
-	void redo();
 	int get_size();
 private:
 	double old_position;
@@ -1743,11 +1740,10 @@ OutPointUndoItem::OutPointUndoItem(
 void OutPointUndoItem::undo()
 {
    edl->set_outpoint(old_position);
-}
-
-void OutPointUndoItem::redo()
-{
-   edl->set_outpoint(new_position);
+// prepare to undo the undo
+	double tmp = new_position;
+	new_position = old_position;
+	old_position = tmp;
 }
 
 int OutPointUndoItem::get_size()
@@ -1877,7 +1873,6 @@ class LabelUndoItem : public UndoStackItem
 public:
       LabelUndoItem(double position1, double position2, EDL *edl);
       void undo();
-      void redo();
       int get_size();
 private:
       double position1;
@@ -1899,11 +1894,6 @@ void LabelUndoItem::undo()
 	edl->labels->toggle_label(position1, position2);
 }
 
-void LabelUndoItem::redo()
-{
-	edl->labels->toggle_label(position1, position2);
-}
-
 int LabelUndoItem::get_size()
 {
    return 20;
diff --git a/cinelerra/undostackitem.C b/cinelerra/undostackitem.C
index 35b37847..991f6f9e 100644
--- a/cinelerra/undostackitem.C
+++ b/cinelerra/undostackitem.C
@@ -23,10 +23,6 @@ void UndoStackItem::undo()
 {
 }
 
-void UndoStackItem::redo()
-{
-}
-
 int UndoStackItem::get_size()
 {
 	return 0;
diff --git a/cinelerra/undostackitem.h b/cinelerra/undostackitem.h
index 669bd6ed..44eda7da 100644
--- a/cinelerra/undostackitem.h
+++ b/cinelerra/undostackitem.h
@@ -12,12 +12,13 @@ public:
 
 	void set_description(char *description);
 
-// These two virtual functions allow derived objects to be pushed
-// on to the undo stack that are more efficient in time and memory
-// usage than the default action of saving before and after copies
-// of the EDL.  
+// This function must be overridden in derived objects.
+// It is called both to undo and to redo an operation.
+// The override must do the following:
+// - change the EDL to undo an operation;
+// - change the internal information of the item so that the next invocation
+//   of undo() does a redo (i.e. undoes the undone operation).
 	virtual void undo();
-	virtual void redo();
 
 // Return the amount of memory used for the data associated with this
 // object in order to enable limiting the amount of memory used by the
-- 
2.11.4.GIT