diff --git a/src/buffer.hh b/src/buffer.hh
index e4410566..d30a125e 100644
--- a/src/buffer.hh
+++ b/src/buffer.hh
@@ -26,9 +26,7 @@ struct BufferCoord : LineAndColumn<BufferCoord>
 
     template<typename T>
     explicit BufferCoord(const LineAndColumn<T>& other)
-        : LineAndColumn(other.line, other.column)
-    {
-    }
+        : LineAndColumn(other.line, other.column) {}
 };
 
 class BufferIterator
diff --git a/src/display_buffer.cc b/src/display_buffer.cc
index f36527be..394fc0fb 100644
--- a/src/display_buffer.cc
+++ b/src/display_buffer.cc
@@ -5,6 +5,76 @@
 namespace Kakoune
 {
 
+BufferString DisplayAtom::content() const
+{
+    if (m_replacement_text.empty())
+        return m_begin.buffer().string(m_begin, m_end);
+    else
+        return m_replacement_text;
+}
+
+template<typename Iterator>
+static DisplayCoord advance_coord(const DisplayCoord& pos,
+                                  Iterator begin, Iterator end)
+{
+    DisplayCoord res = pos;
+    while (begin != end)
+    {
+        if (*begin == '\n')
+        {
+            ++res.line;
+            res.column = 0;
+        }
+        else
+            ++res.column;
+        ++begin;
+    }
+    return res;
+}
+
+DisplayCoord DisplayAtom::end_coord() const
+{
+    if (m_replacement_text.empty())
+        return advance_coord(m_coord, m_begin, m_end);
+    else
+        return advance_coord(m_coord, m_replacement_text.begin(),
+                             m_replacement_text.end());
+}
+
+BufferIterator DisplayAtom::iterator_at(const DisplayCoord& coord) const
+{
+    if (not m_replacement_text.empty() or coord <= m_coord)
+        return m_begin;
+
+    DisplayCoord pos = m_coord;
+    for (BufferIterator it = m_begin; it != m_end; ++it)
+    {
+        if (*it == '\n')
+        {
+            ++pos.line;
+            pos.column = 0;
+        }
+        else
+            ++pos.column;
+
+        if (coord == pos)
+            return it+1;
+        else if (coord < pos)
+            return it;
+    }
+    return m_end;
+}
+
+DisplayCoord DisplayAtom::line_and_column_at(const BufferIterator& iterator) const
+{
+    assert(iterator >= m_begin and iterator < m_end);
+
+    if (not m_replacement_text.empty())
+        return m_coord;
+
+    return advance_coord(m_coord, m_begin, iterator);
+}
+
 DisplayBuffer::DisplayBuffer()
 {
 }
@@ -12,22 +82,47 @@ DisplayBuffer::DisplayBuffer()
 DisplayBuffer::iterator DisplayBuffer::split(iterator atom, const BufferIterator& pos)
 {
     assert(atom < end());
-    assert(pos > atom->begin);
-    assert(pos < atom->end);
-    DisplayAtom new_atom(atom->begin, pos,
-                         atom->fg_color, atom->bg_color, atom->attribute);
+    assert(pos > atom->begin());
+    assert(pos < atom->end());
+    DisplayAtom new_atom(atom->coord(), atom->begin(), pos,
+                         atom->fg_color(), atom->bg_color(), atom->attribute());
 
-    atom->begin = pos;
-    return insert(atom, std::move(new_atom));
+    atom->m_begin = pos;
+    atom->m_coord = new_atom.end_coord();
+    iterator res = insert(atom, std::move(new_atom));
+    check_invariant();
+    return res;
 }
 
 void DisplayBuffer::check_invariant() const
 {
     for (size_t i = 0; i < m_atoms.size(); ++i)
     {
-        assert(m_atoms[i].end > m_atoms[i].begin);
+        assert(m_atoms[i].end() > m_atoms[i].begin());
         if (i > 0)
-            assert(m_atoms[i-1].end == m_atoms[i].begin);
+        {
+            assert(m_atoms[i-1].end() == m_atoms[i].begin());
+            assert(m_atoms[i-1].end_coord() == m_atoms[i].coord());
+        }
+    }
+}
+
+void DisplayBuffer::replace_atom_content(iterator atom,
+                                         const BufferString& replacement)
+{
+    assert(atom < end());
+    atom->m_replacement_text = replacement;
+
+    // update coordinates of subsequents atoms
+    DisplayCoord new_coord = atom->end_coord();
+    while (true)
+    {
+        new_coord = atom->end_coord();
+        ++atom;
+
+        if (atom == end() or new_coord == atom->m_coord)
+            break;
+        atom->m_coord = new_coord;
     }
 }
 
diff --git a/src/display_buffer.hh b/src/display_buffer.hh
index a3451c35..874276a8 100644
--- a/src/display_buffer.hh
+++ b/src/display_buffer.hh
@@ -15,6 +15,10 @@ struct DisplayCoord : LineAndColumn<DisplayCoord>
 {
     DisplayCoord(int line = 0, int column = 0)
         : LineAndColumn(line, column) {}
+
+    template<typename T>
+    explicit DisplayCoord(const LineAndColumn<T>& other)
+        : LineAndColumn(other.line, other.column) {}
 };
 
 typedef int Attribute;
@@ -43,23 +47,45 @@ enum class Color
 
 struct DisplayAtom
 {
-    BufferIterator begin;
-    BufferIterator end;
-    Color          fg_color;
-    Color          bg_color;
-    Attribute      attribute;
-    BufferString   replacement_text;
-
-    DisplayAtom(BufferIterator begin, BufferIterator end,
+    DisplayAtom(const DisplayCoord& coord,
+                const BufferIterator& begin, const BufferIterator& end,
                 Color fg_color = Color::Default,
                 Color bg_color = Color::Default,
                 Attribute attribute = Attributes::Normal)
-        : begin(begin),
-          end(end),
-          fg_color(fg_color),
-          bg_color(bg_color),
-          attribute(attribute)
+        : m_coord(coord),
+          m_begin(begin), m_end(end),
+          m_fg_color(fg_color),
+          m_bg_color(bg_color),
+          m_attribute(attribute)
     {}
+
+    const DisplayCoord&   coord()     const { return m_coord; }
+    const BufferIterator& begin()     const { return m_begin; }
+    const BufferIterator& end()       const { return m_end; }
+    const Color&          fg_color()  const { return m_fg_color; }
+    const Color&          bg_color()  const { return m_bg_color; }
+    const Attribute&      attribute() const { return m_attribute; }
+
+
+    Color&         fg_color()  { return m_fg_color; }
+    Color&         bg_color()  { return m_bg_color; }
+    Attribute&     attribute() { return m_attribute; }
+
+    BufferString   content()    const;
+    DisplayCoord   end_coord()  const;
+    BufferIterator iterator_at(const DisplayCoord& coord) const;
+    DisplayCoord   line_and_column_at(const BufferIterator& iterator) const;
+
+private:
+    friend class DisplayBuffer;
+
+    DisplayCoord   m_coord;
+    BufferIterator m_begin;
+    BufferIterator m_end;
+    Color          m_fg_color;
+    Color          m_bg_color;
+    Attribute      m_attribute;
+    BufferString   m_replacement_text;
 };
 
 class DisplayBuffer
@@ -76,12 +102,17 @@ public:
     iterator insert(iterator where, const DisplayAtom& atom) { return m_atoms.insert(where, atom); }
     iterator split(iterator atom, const BufferIterator& pos);
 
+    void replace_atom_content(iterator atom, const BufferString& replacement);
+
     iterator begin() { return m_atoms.begin(); }
     iterator end()   { return m_atoms.end(); }
 
     const_iterator begin() const { return m_atoms.begin(); }
     const_iterator end()   const { return m_atoms.end(); }
 
+    const DisplayAtom& front() const { return m_atoms.front(); }
+    const DisplayAtom& back()  const { return m_atoms.back(); }
+
     void check_invariant() const;
 private:
     AtomList m_atoms;
diff --git a/src/filters.cc b/src/filters.cc
index 5b306f2f..7e534618 100644
--- a/src/filters.cc
+++ b/src/filters.cc
@@ -10,17 +10,18 @@ void colorize_regex(DisplayBuffer& display_buffer,
          atom_it != display_buffer.end(); ++atom_it)
     {
         boost::match_results<BufferIterator> matches;
-        if (boost::regex_search(atom_it->begin, atom_it->end, matches, ex, boost::match_nosubs))
+        if (boost::regex_search(atom_it->begin(), atom_it->end(),
+                                matches, ex, boost::match_nosubs))
         {
             const BufferIterator& begin = matches.begin()->first;
-            if (begin != atom_it->begin)
+            if (begin != atom_it->begin())
                 atom_it = display_buffer.split(atom_it, begin) + 1;
 
             const BufferIterator& end = matches.begin()->second;
-            if (end != atom_it->end)
+            if (end != atom_it->end())
                 atom_it = display_buffer.split(atom_it, end);
 
-            atom_it->fg_color = color;
+            atom_it->fg_color() = color;
         }
     }
 }
@@ -58,19 +59,32 @@ void expand_tabulations(DisplayBuffer& display_buffer)
     for (auto atom_it = display_buffer.begin();
          atom_it != display_buffer.end(); ++atom_it)
     {
-        for (BufferIterator it = atom_it->begin; it != atom_it->end; ++it)
+        for (BufferIterator it = atom_it->begin(); it != atom_it->end(); ++it)
         {
             if (*it == '\t')
             {
-                if (it != atom_it->begin)
+                if (it != atom_it->begin())
                     atom_it = display_buffer.split(atom_it, it) + 1;
 
-                if (it+1 != atom_it->end)
+                if (it+1 != atom_it->end())
                     atom_it = display_buffer.split(atom_it, it+1);
 
                 BufferCoord pos = it.buffer().line_and_column_at(it);
-                int count = tabstop - (pos.column % tabstop);
-                atom_it->replacement_text = std::string(count, ' ');
+                
+                int column = 0;
+                for (auto line_it = it.buffer().iterator_at({pos.line, 0});
+                     line_it != it; ++line_it)
+                {
+                    assert(*line_it != '\n');
+                    if (*line_it == '\t')
+                        column += tabstop - (column % tabstop);
+                    else
+                       ++column;
+                }
+
+                int count = tabstop - (column % tabstop);
+                display_buffer.replace_atom_content(atom_it,
+                                                    std::string(count, ' '));
             }
         }
     }
diff --git a/src/main.cc b/src/main.cc
index 7f6902df..104721fc 100644
--- a/src/main.cc
+++ b/src/main.cc
@@ -85,15 +85,15 @@ void draw_window(Window& window)
     DisplayCoord position;
     for (const DisplayAtom& atom : window.display_buffer())
     {
-        const std::string content = atom.replacement_text.empty() ?
-            window.buffer().string(atom.begin, atom.end) : atom.replacement_text;
+        assert(position == atom.coord());
+        const std::string content = atom.content();
 
-        set_attribute(A_UNDERLINE, atom.attribute & Underline);
-        set_attribute(A_REVERSE, atom.attribute & Reverse);
-        set_attribute(A_BLINK, atom.attribute & Blink);
-        set_attribute(A_BOLD, atom.attribute & Bold);
+        set_attribute(A_UNDERLINE, atom.attribute() & Underline);
+        set_attribute(A_REVERSE, atom.attribute() & Reverse);
+        set_attribute(A_BLINK, atom.attribute() & Blink);
+        set_attribute(A_BOLD, atom.attribute() & Bold);
 
-        set_color(atom.fg_color, atom.bg_color);
+        set_color(atom.fg_color(), atom.bg_color());
 
         size_t pos = 0;
         size_t end;
diff --git a/src/window.cc b/src/window.cc
index f03bf5d5..50a5e908 100644
--- a/src/window.cc
+++ b/src/window.cc
@@ -60,40 +60,40 @@ public:
             DisplayAtom& atom = *atom_it;
 
             // [###------]
-            if (atom.begin >= sel.begin() and atom.begin < sel.end() and atom.end > sel.end())
+            if (atom.begin() >= sel.begin() and atom.begin() < sel.end() and atom.end() > sel.end())
             {
                 atom_it = display_buffer.split(atom_it, sel.end());
-                atom_it->attribute |= Attributes::Underline;
+                atom_it->attribute() |= Attributes::Underline;
                 ++atom_it;
                 ++sel_it;
             }
             // [---###---]
-            else if (atom.begin < sel.begin() and atom.end > sel.end())
+            else if (atom.begin() < sel.begin() and atom.end() > sel.end())
             {
                 atom_it = display_buffer.split(atom_it, sel.begin());
                 atom_it = display_buffer.split(atom_it + 1, sel.end());
-                atom_it->attribute |= Attributes::Underline;
+                atom_it->attribute() |= Attributes::Underline;
                 ++atom_it;
                 ++sel_it;
             }
             // [------###]
-            else if (atom.begin < sel.begin() and atom.end > sel.begin())
+            else if (atom.begin() < sel.begin() and atom.end() > sel.begin())
             {
                 atom_it = display_buffer.split(atom_it, sel.begin()) + 1;
-                atom_it->attribute |= Attributes::Underline;
+                atom_it->attribute() |= Attributes::Underline;
                 ++atom_it;
             }
             // [#########]
-            else if (atom.begin >= sel.begin() and atom.end <= sel.end())
+            else if (atom.begin() >= sel.begin() and atom.end() <= sel.end())
             {
-                atom_it->attribute |= Attributes::Underline;
+                atom_it->attribute() |= Attributes::Underline;
                 ++atom_it;
             }
             // [---------]
-            else if (atom.begin >= sel.end())
+            else if (atom.begin() >= sel.end())
                 ++sel_it;
             // [---------]
-            else if (atom.end <= sel.begin())
+            else if (atom.end() <= sel.begin())
                 ++atom_it;
             else
                 assert(false);
@@ -124,7 +124,13 @@ void Window::check_invariant() const
 DisplayCoord Window::cursor_position() const
 {
     check_invariant();
-    return line_and_column_at(m_selections.back().last());
+    return line_and_column_at(cursor_iterator());
+}
+
+BufferIterator Window::cursor_iterator() const
+{
+    check_invariant();
+    return m_selections.back().last();
 }
 
 void Window::erase()
@@ -206,26 +212,47 @@ bool Window::redo()
     return m_buffer.redo();
 }
 
-BufferCoord Window::window_to_buffer(const DisplayCoord& window_pos) const
-{
-    return BufferCoord(m_position.line + window_pos.line,
-                       m_position.column + window_pos.column);
-}
-
-DisplayCoord Window::buffer_to_window(const BufferCoord& buffer_pos) const
-{
-    return DisplayCoord(buffer_pos.line - m_position.line,
-                       buffer_pos.column - m_position.column);
-}
-
 BufferIterator Window::iterator_at(const DisplayCoord& window_pos) const
 {
-    return m_buffer.iterator_at(window_to_buffer(window_pos));
+    if (m_display_buffer.begin() == m_display_buffer.end())
+        return m_buffer.begin();
+
+    if (DisplayCoord(0,0) <= window_pos)
+    {
+        for (auto atom_it = m_display_buffer.begin();
+             atom_it != m_display_buffer.end(); ++atom_it)
+        {
+            if (window_pos < atom_it->coord())
+            {
+                const DisplayAtom& atom = *(atom_it - 1);
+                return atom.iterator_at(window_pos);
+            }
+        }
+    }
+
+    return m_buffer.iterator_at(m_position + BufferCoord(window_pos));
 }
 
 DisplayCoord Window::line_and_column_at(const BufferIterator& iterator) const
 {
-    return buffer_to_window(m_buffer.line_and_column_at(iterator));
+    if (m_display_buffer.begin() == m_display_buffer.end())
+        return DisplayCoord(0, 0);
+
+    if (iterator >= m_display_buffer.front().begin() and
+        iterator <  m_display_buffer.back().end())
+    {
+        for (auto& atom : m_display_buffer)
+        {
+            if (atom.end() > iterator)
+            {
+                assert(atom.begin() <= iterator);
+                return atom.line_and_column_at(iterator);
+            }
+        }
+    }
+    BufferCoord coord = m_buffer.line_and_column_at(iterator);
+    return DisplayCoord(coord.line - m_position.line,
+                        coord.column - m_position.column);
 }
 
 void Window::clear_selections()
@@ -268,13 +295,16 @@ BufferString Window::selection_content() const
 void Window::move_cursor(const DisplayCoord& offset, bool append)
 {
     if (not append)
-        move_cursor_to(iterator_at(cursor_position() + offset));
+    {
+        BufferCoord pos = m_buffer.line_and_column_at(cursor_iterator());
+        move_cursor_to(m_buffer.iterator_at(pos + BufferCoord(offset)));
+    }
     else
     {
         for (auto& sel : m_selections)
         {
-            DisplayCoord pos = line_and_column_at(sel.last());
-            sel = Selection(sel.first(), iterator_at(pos + offset));
+            BufferCoord pos = m_buffer.line_and_column_at(sel.last());
+            sel = Selection(sel.first(), m_buffer.iterator_at(pos + BufferCoord(offset)));
         }
         scroll_to_keep_cursor_visible_ifn();
     }
@@ -298,7 +328,7 @@ void Window::update_display_buffer()
     if (begin == end)
         return;
 
-    m_display_buffer.append(DisplayAtom(begin, end));
+    m_display_buffer.append(DisplayAtom(DisplayCoord(0,0), begin, end));
 
     for (auto& filter : m_filters)
     {
@@ -338,7 +368,7 @@ void Window::scroll_to_keep_cursor_visible_ifn()
 
 std::string Window::status_line() const
 {
-    BufferCoord cursor = window_to_buffer(cursor_position());
+    BufferCoord cursor = m_buffer.line_and_column_at(m_selections.back().end());
     std::ostringstream oss;
     oss << m_buffer.name();
     if (m_buffer.is_modified())
diff --git a/src/window.hh b/src/window.hh
index 05141fe2..9ae7862c 100644
--- a/src/window.hh
+++ b/src/window.hh
@@ -42,7 +42,8 @@ public:
     void append(const String& string);
 
     const BufferCoord& position() const { return m_position; }
-    DisplayCoord cursor_position() const;
+    DisplayCoord   cursor_position() const;
+    BufferIterator cursor_iterator() const;
 
     Buffer& buffer() const { return m_buffer; }
 
@@ -80,9 +81,6 @@ private:
     void insert_noundo(const String& string);
     void append_noundo(const String& string);
 
-    BufferCoord  window_to_buffer(const DisplayCoord& window_pos) const;
-    DisplayCoord buffer_to_window(const BufferCoord& buffer_pos) const;
-
     friend class IncrementalInserter;
     IncrementalInserter* m_current_inserter;