diff --git a/.gitattributes b/.gitattributes
index 14f58ea004..79bfcd81a7 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -5404,6 +5404,7 @@ components/tachart/fpdoc/descr.lst svneol=native#text/plain
 components/tachart/fpdoc/input.lst svneol=native#text/plain
 components/tachart/fpdoc/tachartaxis.xml svneol=native#text/plain
 components/tachart/fpdoc/tachartaxisutils.xml svneol=native#text/xml
+components/tachart/fpdoc/tachartliveview.xml svneol=native#text/xml
 components/tachart/fpdoc/tachartutils.xml svneol=native#text/plain
 components/tachart/fpdoc/tacustomseries.xml svneol=native#text/plain
 components/tachart/fpdoc/tacustomsource.xml svneol=native#text/xml
@@ -5415,6 +5416,7 @@ components/tachart/fpdoc/talegend.xml svneol=native#text/plain
 components/tachart/fpdoc/tamath.xml svneol=native#text/xml
 components/tachart/fpdoc/taseries.xml svneol=native#text/plain
 components/tachart/fpdoc/tasources.xml svneol=native#text/plain
+components/tachart/fpdoc/tatools.xml svneol=native#text/xml
 components/tachart/fpdoc/tatypes.xml svneol=native#text/plain
 components/tachart/fpvectorial/tachartfpvectorial.lpk svneol=native#text/plain
 components/tachart/fpvectorial/tachartfpvectorial.pas svneol=native#text/pascal
diff --git a/components/tachart/demo/charteditor/ceaxisdlg.lfm b/components/tachart/demo/charteditor/ceaxisdlg.lfm
index 59b7ccc6d4..645ab6aab0 100644
--- a/components/tachart/demo/charteditor/ceaxisdlg.lfm
+++ b/components/tachart/demo/charteditor/ceaxisdlg.lfm
@@ -11,7 +11,7 @@ object ChartAxisEditor: TChartAxisEditor
   OnCreate = FormCreate
   OnShow = FormShow
   Position = poScreenCenter
-  LCLVersion = '2.1.0.0'
+  LCLVersion = '2.3.0.0'
   object ButtonPanel: TButtonPanel
     Left = 6
     Height = 34
diff --git a/components/tachart/demo/charteditor/ceaxisdlg.pas b/components/tachart/demo/charteditor/ceaxisdlg.pas
index 50537b7070..18c5a3cf78 100644
--- a/components/tachart/demo/charteditor/ceaxisdlg.pas
+++ b/components/tachart/demo/charteditor/ceaxisdlg.pas
@@ -179,8 +179,17 @@ begin
 end;
 
 procedure TChartAxisEditor.OKButtonClick(Sender: TObject);
+var
+  msg: String;
+  C: TWinControl;
 begin
-  FOKClicked := true;
+  if not FAxisFrame.Validate(msg, C) then
+  begin
+    C.SetFocus;
+    MessageDlg(msg, mtError, [mbOK], 0);
+    ModalResult := mrNone;
+  end else
+    FOKClicked := true;
 end;
 
 procedure TChartAxisEditor.Prepare(Axis: TChartAxis;
diff --git a/components/tachart/demo/charteditor/ceaxisframe.lfm b/components/tachart/demo/charteditor/ceaxisframe.lfm
index 45d613caa0..629ff4b53c 100644
--- a/components/tachart/demo/charteditor/ceaxisframe.lfm
+++ b/components/tachart/demo/charteditor/ceaxisframe.lfm
@@ -40,23 +40,24 @@ object ChartAxisFrame: TChartAxisFrame
     Height = 446
     Top = 25
     Width = 646
-    ActivePage = pgLabels
+    ActivePage = pgGrid
     Align = alClient
-    TabIndex = 1
+    TabIndex = 2
     TabOrder = 1
+    OnChanging = PageControlChanging
     object pgTitle: TTabSheet
       Caption = 'Title'
-      ClientHeight = 378
+      ClientHeight = 418
       ClientWidth = 638
       object TitleMemoPanel: TPanel
         Left = 8
-        Height = 151
+        Height = 191
         Top = 8
         Width = 622
         Align = alClient
         BorderSpacing.Around = 8
         BevelOuter = bvNone
-        ClientHeight = 151
+        ClientHeight = 191
         ClientWidth = 622
         TabOrder = 0
         object lblTitle: TLabel
@@ -68,7 +69,6 @@ object ChartAxisFrame: TChartAxisFrame
           Width = 21
           BorderSpacing.Top = 2
           Caption = 'Text'
-          ParentColor = False
         end
         object mmoTitle: TMemo
           AnchorSideLeft.Control = lblTitle
@@ -79,7 +79,7 @@ object ChartAxisFrame: TChartAxisFrame
           AnchorSideBottom.Control = TitleMemoPanel
           AnchorSideBottom.Side = asrBottom
           Left = 0
-          Height = 130
+          Height = 170
           Top = 21
           Width = 622
           Anchors = [akTop, akLeft, akRight, akBottom]
@@ -109,7 +109,7 @@ object ChartAxisFrame: TChartAxisFrame
       object TitleParamsPanel: TPanel
         Left = 8
         Height = 203
-        Top = 167
+        Top = 207
         Width = 622
         Align = alBottom
         BorderSpacing.Around = 8
@@ -199,7 +199,6 @@ object ChartAxisFrame: TChartAxisFrame
           Width = 45
           Caption = 'Distance'
           FocusControl = seTitleDistance
-          ParentColor = False
         end
         object seTitleDistance: TSpinEdit
           AnchorSideLeft.Control = lblTitleDistance
@@ -248,7 +247,6 @@ object ChartAxisFrame: TChartAxisFrame
           BorderSpacing.Left = 16
           BorderSpacing.Top = 6
           Caption = 'Automatic'
-          ParentColor = False
         end
         object cbAutoMax: TCheckBox
           AnchorSideLeft.Control = lblAutomatic
@@ -427,7 +425,6 @@ object ChartAxisFrame: TChartAxisFrame
           Top = 31
           Width = 38
           Caption = 'Format'
-          ParentColor = False
         end
         object seLabelDistance: TSpinEdit
           AnchorSideLeft.Control = edLabelFormat
@@ -453,7 +450,6 @@ object ChartAxisFrame: TChartAxisFrame
           Width = 45
           Caption = 'Distance'
           FocusControl = seLabelDistance
-          ParentColor = False
         end
       end
       object Bevel2: TBevel
@@ -524,7 +520,6 @@ object ChartAxisFrame: TChartAxisFrame
           Width = 67
           BorderSpacing.Left = 16
           Caption = 'Outer length'
-          ParentColor = False
         end
         object lblTickInnerLength: TLabel
           AnchorSideLeft.Control = lblTickLength
@@ -535,7 +530,6 @@ object ChartAxisFrame: TChartAxisFrame
           Top = 37
           Width = 64
           Caption = 'Inner length'
-          ParentColor = False
         end
         object cbTickColor: TColorButton
           AnchorSideTop.Side = asrCenter
@@ -555,8 +549,8 @@ object ChartAxisFrame: TChartAxisFrame
     end
     object pgGrid: TTabSheet
       Caption = 'Grid'
-      ClientHeight = 378
-      ClientWidth = 513
+      ClientHeight = 418
+      ClientWidth = 638
       object gbGrid: TGroupBox
         AnchorSideLeft.Control = pgGrid
         AnchorSideTop.Control = pgGrid
@@ -584,14 +578,15 @@ object ChartAxisFrame: TChartAxisFrame
           BorderSpacing.Right = 16
           BorderSpacing.Bottom = 8
           Caption = 'Visible'
+          OnChange = cbGridVisibleChange
           TabOrder = 0
         end
       end
     end
     object pgLine: TTabSheet
       Caption = 'Line'
-      ClientHeight = 378
-      ClientWidth = 513
+      ClientHeight = 418
+      ClientWidth = 638
       object gbFrame: TGroupBox
         AnchorSideLeft.Control = pgLine
         AnchorSideTop.Control = pgLine
@@ -599,19 +594,19 @@ object ChartAxisFrame: TChartAxisFrame
         Left = 8
         Height = 119
         Top = 8
-        Width = 275
+        Width = 400
         Anchors = [akTop, akLeft, akRight]
         BorderSpacing.Left = 8
         BorderSpacing.Top = 8
         Caption = 'gbFrame'
         ClientHeight = 99
-        ClientWidth = 271
+        ClientWidth = 396
         TabOrder = 0
         object cbFrameVisible: TCheckBox
           Left = 16
           Height = 19
           Top = 8
-          Width = 239
+          Width = 364
           Align = alTop
           BorderSpacing.Left = 16
           BorderSpacing.Top = 8
@@ -631,18 +626,18 @@ object ChartAxisFrame: TChartAxisFrame
         Left = 8
         Height = 137
         Top = 143
-        Width = 275
+        Width = 400
         Anchors = [akTop, akLeft, akRight]
         BorderSpacing.Top = 16
         Caption = 'gbAxisLine'
         ClientHeight = 117
-        ClientWidth = 271
+        ClientWidth = 396
         TabOrder = 1
         object cbAxisLineVisible: TCheckBox
           Left = 16
           Height = 19
           Top = 8
-          Width = 239
+          Width = 364
           Align = alTop
           BorderSpacing.Left = 16
           BorderSpacing.Top = 8
@@ -659,7 +654,7 @@ object ChartAxisFrame: TChartAxisFrame
         AnchorSideTop.Control = gbFrame
         AnchorSideRight.Control = pgLine
         AnchorSideRight.Side = asrBottom
-        Left = 307
+        Left = 432
         Height = 156
         Top = 8
         Width = 200
@@ -693,7 +688,6 @@ object ChartAxisFrame: TChartAxisFrame
           Top = 39
           Width = 61
           Caption = 'Base length'
-          ParentColor = False
         end
         object lblArrowLength: TLabel
           AnchorSideLeft.Control = cbArrowVisible
@@ -704,7 +698,6 @@ object ChartAxisFrame: TChartAxisFrame
           Top = 70
           Width = 37
           Caption = 'Length'
-          ParentColor = False
         end
         object lblArrowWidth: TLabel
           AnchorSideLeft.Control = cbArrowVisible
@@ -715,7 +708,6 @@ object ChartAxisFrame: TChartAxisFrame
           Top = 101
           Width = 32
           Caption = 'Width'
-          ParentColor = False
         end
         object seArrowBaseLength: TSpinEdit
           AnchorSideLeft.Control = lblArrowBaseLength
diff --git a/components/tachart/demo/charteditor/ceaxisframe.pas b/components/tachart/demo/charteditor/ceaxisframe.pas
index 2b5834ecfe..f8eed86eb7 100644
--- a/components/tachart/demo/charteditor/ceaxisframe.pas
+++ b/components/tachart/demo/charteditor/ceaxisframe.pas
@@ -76,6 +76,7 @@ type
     procedure cbAutoMinChange(Sender: TObject);
     procedure cbAxisLineVisibleChange(Sender: TObject);
     procedure cbFrameVisibleChange(Sender: TObject);
+    procedure cbGridVisibleChange(Sender: TObject);
     procedure cbInvertedChange(Sender: TObject);
     procedure cbLabelsVisibleChange(Sender: TObject);
     procedure cbShowChange(Sender: TObject);
@@ -83,6 +84,7 @@ type
     procedure cbTitleVisibleChange(Sender: TObject);
     procedure edLabelFormatEditingDone(Sender: TObject);
     procedure mmoTitleChange(Sender: TObject);
+    procedure PageControlChanging(Sender: TObject; var AllowChange: Boolean);
     procedure rgTitleAlignmentClick(Sender: TObject);
     procedure seArrowBaseLengthChange(Sender: TObject);
     procedure seArrowLengthChange(Sender: TObject);
@@ -95,6 +97,7 @@ type
     procedure seTitleDistanceChange(Sender: TObject);
   private
     FAxis: TChartAxis;
+    FAxisMin, FAxisMax: Double;
     FTitleFontFrame: TChartFontFrame;
     FTitleShapeBrushPenMarginsFrame: TChartShapeBrushPenMarginsFrame;
     FLabelFontFrame: TChartFontFrame;
@@ -119,9 +122,12 @@ type
     procedure CalculatePreferredSize(var PreferredWidth, PreferredHeight: integer;
       {%H-}WithThemeSpace: Boolean); override;
     function GetChart: TChart;
+    function GetRealAxisMax: Double;
+    function GetRealAxisMin: Double;
   public
     constructor Create(AOwner: TComponent); override;
     procedure Prepare(Axis: TChartAxis);
+    function Validate(out AMsg: String; out AControl: TWinControl): Boolean;
     property Page: TChartAxisEditorPage read GetPage write SetPage;
   end;
 
@@ -266,7 +272,7 @@ end;
 
 procedure TChartAxisFrame.cbAxisLineVisibleChange(Sender: TObject);
 begin
-  FAxis.Grid.Visible := cbGridVisible.Checked;
+  FAxis.AxisPen.Visible := cbAxisLineVisible.Checked;
 end;
 
 procedure TChartAxisFrame.cbFrameVisibleChange(Sender: TObject);
@@ -274,9 +280,14 @@ begin
   GetChart.Frame.Visible := cbFrameVisible.Checked;
 end;
 
+procedure TChartAxisFrame.cbGridVisibleChange(Sender: TObject);
+begin
+  FAxis.Grid.Visible := cbGridVisible.Checked;
+end;
+
 procedure TChartAxisFrame.cbInvertedChange(Sender: TObject);
 begin
-  FAxis.Inverted := not FAxis.Inverted;
+  FAxis.Inverted := cbInverted.Checked;
 end;
 
 procedure TChartAxisFrame.cbLabelsVisibleChange(Sender: TObject);
@@ -336,6 +347,22 @@ begin
   Result := TChartAxisEditorPage(PageControl.ActivePageIndex);
 end;
 
+function TChartAxisFrame.GetRealAxisMax: Double;
+begin
+  if cbAutoMax.Checked then
+    Result := FAxisMax
+  else
+    Result := seMaximum.Value;
+end;
+
+function TChartAxisFrame.GetRealAxisMin: Double;
+begin
+  if cbAutoMin.Checked then
+    Result := FAxisMin
+  else
+    Result := seMinimum.Value;
+end;
+
 procedure TChartAxisFrame.LabelChangedHandler(Sender: TObject);
 begin
   GetChart.Invalidate;
@@ -356,6 +383,20 @@ begin
   FAxis.Title.Caption := mmoTitle.Lines.Text;
 end;
 
+procedure TChartAxisFrame.PageControlChanging(Sender: TObject;
+  var AllowChange: Boolean);
+var
+  msg: String;
+  C: TWinControl;
+begin
+  if not Validate(msg, C) then
+  begin
+    C.SetFocus;
+    MessageDlg(msg, mtError, [mbOK], 0);
+    AllowChange := false;
+  end;
+end;
+
 procedure TChartAxisFrame.Prepare(Axis: TChartAxis);
 begin
   FAxis := Axis;
@@ -379,8 +420,9 @@ begin
   end;
 
   // Page "Labels"
-  seMaximum.Value := Axis.Range.Max;
-  seMinimum.Value := Axis.Range.Min;
+  GetChart.GetAllSeriesAxisLimits(Axis, FAxisMin, FAxisMax);
+  seMaximum.Value := IfThen(Axis.Range.UseMax, Axis.Range.Max, FAxisMax);
+  seMinimum.Value := IfThen(Axis.Range.UseMin, Axis.Range.Min, FAxisMin);
   cbAutoMax.Checked := not Axis.Range.UseMax;
   cbAutoMin.Checked := not Axis.Range.UseMin;
   cbInverted.Checked := Axis.Inverted;
@@ -491,6 +533,23 @@ begin
   FAxis.Title.Shape := AShape;
 end;
 
+function TChartAxisFrame.Validate(out AMsg: String; out AControl: TWinControl): Boolean;
+begin
+  Result := false;
+  if GetRealAxisMin >= GetRealAxisMax then
+  begin
+    AMsg := 'The axis minimum must be smaller than the axis maximum.';
+    if seMaximum.Visible then
+      AControl := seMaximum
+    else if seMinimum.Visible then
+      AControl := seMinimum
+    else
+      AControl := cbAutoMax;
+    exit;
+  end;
+  Result := true;
+end;
+
 
 end.
 
diff --git a/components/tachart/demo/charteditor/cecharteditor.lfm b/components/tachart/demo/charteditor/cecharteditor.lfm
index 4711fa6c11..a35e70f8bb 100644
--- a/components/tachart/demo/charteditor/cecharteditor.lfm
+++ b/components/tachart/demo/charteditor/cecharteditor.lfm
@@ -10,7 +10,7 @@ object ChartEditorForm: TChartEditorForm
   OnCloseQuery = FormCloseQuery
   OnCreate = FormCreate
   OnDestroy = FormDestroy
-  LCLVersion = '2.1.0.0'
+  LCLVersion = '2.3.0.0'
   object ButtonPanel: TButtonPanel
     Left = 6
     Height = 34
@@ -41,6 +41,7 @@ object ChartEditorForm: TChartEditorForm
     Constraints.MinWidth = 120
     Images = ChartImagesDM.ChartImages
     TabOrder = 1
+    OnChanging = TreeChanging
     OnDeletion = TreeDeletion
     OnSelectionChanged = TreeSelectionChanged
   end
@@ -110,7 +111,6 @@ object ChartEditorForm: TChartEditorForm
       Font.Color = clWindow
       Font.Height = -16
       Font.Style = [fsBold]
-      ParentColor = False
       ParentFont = False
     end
     object Image1: TImage
diff --git a/components/tachart/demo/charteditor/cecharteditor.pas b/components/tachart/demo/charteditor/cecharteditor.pas
index ea4011646c..ad411709bd 100644
--- a/components/tachart/demo/charteditor/cecharteditor.pas
+++ b/components/tachart/demo/charteditor/cecharteditor.pas
@@ -29,6 +29,8 @@ type
     procedure FormCreate(Sender: TObject);
     procedure FormDestroy(Sender: TObject);
     procedure OKButtonClick(Sender: TObject);
+    procedure TreeChanging(Sender: TObject; Node: TTreeNode;
+      var AllowChange: Boolean);
     procedure TreeDeletion(Sender: TObject; Node: TTreeNode);
     procedure TreeSelectionChanged(Sender: TObject);
   private
@@ -57,6 +59,7 @@ type
     procedure SaveChartToStream;
     procedure SelectNode(ANode: TTreeNode);
     procedure RestoreChartFromStream;
+    function Validate(ANode: TTreeNode; out AMsg: String; out AControl: TWinControl): boolean;
   public
     procedure SelectAxis(AxisIndex: Integer; APage: TChartAxisEditorPage);
     procedure SelectFooter;
@@ -210,8 +213,17 @@ begin
 end;
 
 procedure TChartEditorForm.ApplyButtonClick(Sender: TObject);
+var
+  msg: String;
+  C: TWinControl;
 begin
-  RestoreChartFromStream;
+  if not Validate(Tree.Selected, msg, C) then
+  begin
+    C.SetFocus;
+    MessageDlg(msg, mtError, [mbOK], 0);
+    ModalResult := mrNone;
+  end else
+    RestoreChartFromStream;
 end;
 
 procedure TChartEditorForm.FormActivate(Sender: TObject);
@@ -338,8 +350,31 @@ begin
 end;
 
 procedure TChartEditorForm.OKButtonClick(Sender: TObject);
+var
+  msg: String;
+  C: TWinControl;
 begin
-  FOKClicked := true;
+  if not Validate(Tree.selected, msg, C) then
+  begin
+    C.SetFocus;
+    MessageDlg(msg, mtError, [mbOK], 0);
+    ModalResult := mrNone;
+  end else
+    FOKClicked := true;
+end;
+
+procedure TChartEditorForm.TreeChanging(Sender: TObject; Node: TTreeNode;
+  var AllowChange: Boolean);
+var
+  msg: String;
+  C: TWinControl;
+begin
+  if not Validate(Tree.Selected, msg, C) then
+  begin
+    C.SetFocus;
+    MessageDlg(msg, mtError, [mbOk], 0);
+    AllowChange := false;
+  end;
 end;
 
 procedure TChartEditorForm.PopulateAxes(AChart: TChart);
@@ -559,5 +594,19 @@ begin
   ChartImagesDM.ChartImages.GetBitmap(Tree.Selected.ImageIndex, Image1.Picture.Bitmap);
 end;
 
+function TChartEditorForm.Validate(ANode: TTreeNode; out AMsg: String;
+  out AControl: TWinControl): Boolean;
+begin
+  if ANode = nil then
+    exit(true);
+
+  if TObject(ANode.Data) is TChartAxisFrame then
+  begin
+    Result := TChartAxisFrame(ANode.Data).Validate(AMsg, AControl);
+    if not Result then exit;
+  end;
+  Result := true;
+end;
+
 end.
 
diff --git a/components/tachart/demo/charteditor/charteditordemo.lpi b/components/tachart/demo/charteditor/charteditordemo.lpi
index b1ef559ef0..f3897f390d 100644
--- a/components/tachart/demo/charteditor/charteditordemo.lpi
+++ b/components/tachart/demo/charteditor/charteditordemo.lpi
@@ -198,6 +198,7 @@
     </CodeGeneration>
     <Linking>
       <Debugging>
+        <DebugInfoType Value="dsDwarf2Set"/>
         <TrashVariables Value="True"/>
       </Debugging>
       <Options>
diff --git a/components/tachart/fpdoc/tachartliveview.xml b/components/tachart/fpdoc/tachartliveview.xml
new file mode 100644
index 0000000000..fb4ce8bbc9
--- /dev/null
+++ b/components/tachart/fpdoc/tachartliveview.xml
@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<fpdoc-descriptions><package name="TAChartLazarusPkg"><module name="TAChartLiveView"><element name="TChartLiveView"><short><var>TChartLiveView</var> is a component optimized for displaying a long array of incoming data in a viewport with only the most recent data while older data are flowing to the left out of the vewport.</short><descr>The viewport is updated whenever the full extent of the associated chart changes. However, when property <var>Active</var> is set to <var>false</var> the viewport is fixed -- this is a setting which allows the user to review older data, or change the extent while still new data are coming at the same time.
+</descr>
+      </element><element name="TChartLiveView.Chart"><short>Chart on which the LiveView operates</short>
+      </element><element name="TChartLiveView.ViewportSize"><short>Width of the visible viewport on the x axis, in graph units</short><descr>If set to 0, the width of the current <var>LogicalExtent</var> is used instead.
+</descr>
+      </element><element name="TChartLiveView.Active"><short>Allows to turn the scrolling controlled by the component ON and OFF.</short>
+      </element><element name="TChartLiveView.ExtentY"><short>Mode determining how the vertical y axis is displayed in the scrolling viewport</short>
+      <descr><p><var>lveAuto</var>: adjusts the height to the visible data range automatically. This works also when the chart contains several y axes.
+</p><p><var>lveFull</var>: freezes the height to the full extent of the chart.</p><p><var>lveLogical</var>: freezes the height to the logical extent of the chart.</p><p><var>lveMultiAxisRange</var> tries to use a predefined <var>Range</var> of the y axes in case of a multi-axis chart. Use the <var>Range.Min</var>, <var>Range.Max</var>, <var>Range.UseMin</var> and <var>Range.UseMax</var> properties to set up the axis range. Note that the range is extended automatically when a series attached to this axis contains out-of-range y values. When no range is specified (i.e., <var>axis.Range.UseMin=false</var> and <var>axis.Range.UseMax=false</var>) the behaviour is similar to <var>lveAuto</var>.</p>
+        </descr>
+      </element><element name="TChartLiveView.Create"><short>Constructor of the <var>TChartLiveView</var>
+        </short>
+      </element><element name="TChartLiveView.Destroy"><short>Destructor of the <var>TChartLiveView</var>
+        </short>
+      </element>
+    </module>
+  </package>
+</fpdoc-descriptions>
diff --git a/components/tachart/fpdoc/tacustomseries.xml b/components/tachart/fpdoc/tacustomseries.xml
index 2f3a816bbf..1183591dde 100644
--- a/components/tachart/fpdoc/tacustomseries.xml
+++ b/components/tachart/fpdoc/tacustomseries.xml
@@ -7,7 +7,7 @@
       </element>
       <element name="TChartGetMarkEvent"/>
       <element name="TChartSeries.Count">
-        <short>Return number of points in the series.</short>
+        <short>Returns the number of points in the series.</short>
       </element>
       <element name="TChartSeries.Add">
         <short>Add new point to the right of the series.</short>
@@ -32,7 +32,7 @@
       <element name="TChartSeries.ListSource">
         <errors><link id="TASources.EEditableSourceRequired">EEditableSourceRequired</link>
         </errors>
-        <short>Verify that the data source is editable and return it.</short>
+        <short>Verifies that the data source is editable and returns it (or <var>nil</var> if the source is not a <var>TListChartSource</var>)</short>
       </element>
       <element name="TChartSeries.Clear">
         <short>Remove all points from the series.</short>
@@ -40,12 +40,10 @@
         </descr>
       </element>
       <element name="TChartSeries.Delete">
-        <errors>
-          <link id="TASources.EEditableSourceRequired">EEditableSourceRequired</link>
+        <errors><link id="TASources.EEditableSourceRequired">EEditableSourceRequired</link>
         </errors>
-        <short>Remove point by index.</short>
-        <descr>
-          <p>Requires <link id="TChartSeries.ListSource">editable data source</link>.</p>
+        <short>Removes  a data point by index.</short>
+        <descr><p>Requires <link id="TChartSeries.ListSource">editable data source</link>.</p>
         </descr>
       </element>
       <element name="TChartSeries.SetXValue"/>
@@ -55,6 +53,8 @@
       </element>
       <element name="TChartSeries.Marks">
         <short>Mark parameters.</short>
+      <descr>Marks are the text labels drawn for each data point.
+</descr>
       </element>
       <element name="TChartSeries.OnGetMark">
         <short>Called before the drawing of each mark.</short>
@@ -81,7 +81,7 @@ from a <link id="TACustomSource.TCustomChartSource"><var>chart source</var>
         <short>Return the label for the point number <var>AIndex</var> formatted as per <var>Marks</var> property</short>
       </element>
       <element name="TChartSeries.Extent">
-        <short>Return the bounding rectangle for all points in the serie.</short>
+        <short>Returns the bounding rectangle for all points in the serie.</short>
         <seealso><link id="TASources.TCustomChartSource.Extent">TCustomChartSource.Extent</link>
         </seealso>
       </element>
@@ -192,6 +192,20 @@ per data points than specified by <link id="TChartSeriesGetXYCountNeeded"><var>G
 By default, i.e. <var>DepthBrightnessDelta=0</var>, the series sides have the same color as the series itself.
 </descr>
       </element>
+    <element name="TChartSeries.FindYRange"><short>Finds the y maximum and minimum of the series data having an x between AXMin and AXMax</short>
+      </element><element name="TChartSeries.IsEmpty"><short>Returns true when the series contains no data.</short>
+      </element><element name="TChartSeries.LastValueIndex"><short>Returns the index of the last data point.</short>
+      </element><element name="TChartSeries.MaxXValue"><short>Returns the largest x value</short>
+      </element><element name="TChartSeries.MinXValue"><short>Returns the smallest x value</short>
+      </element><element name="TChartSeries.MaxYValue"><short>Returns the largest y value</short>
+      </element><element name="TChartSeries.MinYValue"><short>Returns the smallest y value</short>
+      </element><element name="TChartSeries.XValue"><short>Returns the x value of the data point with the given index</short>
+      </element><element name="TChartSeries.YValue"><short>Returns the y value of the data point with the given index</short>
+      </element><element name="TChartSeries.XValues"><short>If a source provides data points with multiple x values, the x value with the index <var>AXIndex</var> is returned for the data point at index <var>AIndex</var>
+        </short>
+      </element><element name="TChartSeries.YValues"><short>If a source provides data points with multiple y values, the y value with the index <var>AYIndex</var> is returned for the data point at index <var>AIndex</var>
+        </short>
+      </element>
     </module>
   </package>
 </fpdoc-descriptions>
diff --git a/components/tachart/fpdoc/tagraph.xml b/components/tachart/fpdoc/tagraph.xml
index 9970c1193b..7039ce2153 100644
--- a/components/tachart/fpdoc/tagraph.xml
+++ b/components/tachart/fpdoc/tagraph.xml
@@ -268,10 +268,7 @@ For example, <link id="TASeries.TPieSeries">pie series</link> displays a separat
       </element>
       <element name="TChart.YImageToGraph">
         <short>Converts the Y coordinate of a point from image units to graph units.</short>
-        <seealso>
-          <link id="TChart.YGraphToImage"/>
-          <link id="TChart.XImageToGraph"/>
-          <link id="TChart.ImageToGraph"/>
+        <seealso><link id="TChart.YGraphToImage"/><link id="TChart.XImageToGraph"/><link id="TChart.ImageToGraph"/>
         </seealso>
       </element>
       <element name="TChart.CurrentExtent">
@@ -316,7 +313,9 @@ chart margin and the space reserved for series marks.
       </element>
       <element name="Register" skip="1"/>
       <element name="RegisterSeriesClass" skip="1"/>
-      <element name="TChart.EraseBackground" skip="1"/>
+      <element name="TChart.EraseBackground" skip="1"><short>This overridden background painting method does nothing because the background will be painted over anyway.</short><descr>The inherited behaviour is ignored.
+</descr>
+      </element>
       <element name="TChart.GetChildren" skip="1"/>
       <element name="TChart.Paint" skip="1"/>
       <element name="TChart.SetChildOrder" skip="1"/>
@@ -326,10 +325,10 @@ chart margin and the space reserved for series marks.
       </element>
       <element name="TChart.PaintOnCanvas.Draw"/>
       <element name="TChart.Draw">
-        <short>Draws the chart usung the given drawing back-end</short>
+        <short>Draws the chart using the given drawing back-end</short>
         <descr>This method draws the chart by means of the given drawing back-end, 
 <var>Drawer</var>. Unlike 
-<var>PaintOnCanvas</var> the chart can be drawn on non-canvas devices, such as a svg file.
+<var>PaintOnCanvas</var> the chart can be drawn on non-canvas devices, such as a svg file or OpenGL context.
 </descr>
         <seealso><link id=""/>
         </seealso>
@@ -659,6 +658,15 @@ as a replacement.
 </descr>
       </element><element name="TChart.Proportional"><short><var>Proportional</var>, when set to <var>true</var>, applies the same scaling factor to the x and y axis.</short>
       </element>
+    <element name="TChart.ScalingValid"><short>Indicates whether the scaling parameters for the conversion between graph and image coordinates have valid values.</short>
+      </element><element name="TChart.ActiveToolIndex"><short>Returns the index of the currently active chart tool in the toolset attached to the chart.</short>
+      </element>
+    <element name="TChart.MouseDown"><short>The inherited handler for MouseDown events is overridden to dispatch the event to the ChartToolset assigned to the chart.</short>
+      </element><element name="TChart.MouseMove"><short>The inherited handler for MouseMove events is overridden to dispatch the event to the ChartToolset assigned to the chart.</short>
+      </element><element name="TChart.MouseUp"><short>The inherited handler for MouseUp events is overridden to dispatch the event to the ChartToolset assigned to the chart.</short>
+      </element>
+      <element name="TChart.GetAllSeriesAxisLimits"><short>Determines the data range covered by all series assigned to the specified axis. Minimum and maximum are returned in axis units.</short>
+      </element>
     </module>
   </package>
 </fpdoc-descriptions>
diff --git a/components/tachart/fpdoc/tatools.xml b/components/tachart/fpdoc/tatools.xml
new file mode 100644
index 0000000000..f1f69ad4ae
--- /dev/null
+++ b/components/tachart/fpdoc/tatools.xml
@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<fpdoc-descriptions><package name="TAChartLazarusPkg"><module name="TATools"><element name="TZoomDragTool"><short>Tool for zooming while dragging the mouse over the area to be magnified</short>
+      </element><element name="TZoomDragTool.EscapeCancels"/><element name="TChartTool.EscapeCancels"><short>Cancels the current operation of the chart tool by pressing the ESC key</short><descr>When the property <var>EscapeCancels</var> is true the current operation of the currently active chart tool, e.g. dragging the mouse for zooming, can be aborted by pressing the ESC key.
+</descr>
+      </element>
+    </module>
+  </package>
+</fpdoc-descriptions>
diff --git a/components/tachart/tachartliveview.pas b/components/tachart/tachartliveview.pas
index 7d31a3cc01..3247326d22 100644
--- a/components/tachart/tachartliveview.pas
+++ b/components/tachart/tachartliveview.pas
@@ -1,3 +1,24 @@
+{
+ /***************************************************************************
+                              TAChartLiveView.pas
+                              -------------------
+
+ TChartLiveView is a component optimized for displaying a long array of incoming
+ data in a viewport with only the most recent data while older data are flowing
+ to the left out of the viewport.
+
+ It was created based on the following forum discussions:
+ - https://forum.lazarus.freepascal.org/index.php/topic,15037.html
+ - https://forum.lazarus.freepascal.org/index.php/topic,50759.0.html
+ - https://forum.lazarus.freepascal.org/index.php/topic,55266.html
+
+ See the file COPYING.modifiedLGPL.txt, included in this distribution,
+ for details about the license.
+ *****************************************************************************
+
+  Author: Werner Pamler
+}
+
 unit TAChartLiveView;
 
 {$mode objfpc}{$H+}
@@ -8,21 +29,33 @@ uses
   Classes, SysUtils, TAGraph, TAChartUtils;
 
 type
-  TChartLiveViewExtentY = (lveAuto, lveFull, lveLogical);
+  TChartLiveViewExtentY = (lveAuto, lveFull, lveLogical, lveMultiAxisRange);
+
+  { TChartLiveView }
 
   TChartLiveView = class(TComponent)
+  private
+    type
+      TLVAxisRange = record
+        Min, Max: double;
+        UseMin, UseMax: Boolean;
+      end;
   private
     FActive: Boolean;
     FChart: TChart;
     FExtentY: TChartLiveViewExtentY;
     FListener: TListener;
     FViewportSize: Double;
+    FAxisRanges: Array of TLVAxisRange;
     procedure FullExtentChanged(Sender: TObject);
     procedure SetActive(const AValue: Boolean);
     procedure SetChart(const AValue: TChart);
     procedure SetExtentY(const AValue: TChartLiveViewExtentY);
     procedure SetViewportSize(const AValue: Double);
     procedure UpdateViewport;
+  protected
+    procedure RestoreAxisRanges;
+    procedure StoreAxisRanges;
   public
     constructor Create(AOwner: TComponent); override;
     destructor Destroy; override;
@@ -39,7 +72,7 @@ procedure Register;
 implementation
 
 uses
-  Math, TACustomSeries;
+  Math, TAChartAxis, TAChartAxisUtils, TACustomSeries;
 
 constructor TChartLiveView.Create(AOwner: TComponent);
 begin
@@ -53,6 +86,8 @@ begin
   inherited;
 end;
 
+{ A new data point has been added to the chart so that the full extent changes.
+  As a consequence the viewport of the live view must be updated. }
 procedure TChartLiveView.FullExtentChanged(Sender: TObject);
 begin
   if (not FActive) or (FChart = nil) then
@@ -60,14 +95,46 @@ begin
   UpdateViewport;
 end;
 
+procedure TChartLiveView.RestoreAxisRanges;
+var
+  i: Integer;
+  ax: TChartAxis;
+begin
+  if FChart = nil then
+    exit;
+
+  for i := 0 to FChart.AxisList.Count-1 do
+  begin
+    ax := FChart.AxisList[i];
+    ax.Range.Max := FAxisRanges[i].Max;
+    ax.Range.Min := FAxisRanges[i].Min;
+    ax.Range.UseMax := FAxisRanges[i].UseMax;
+    ax.Range.UseMin := FAxisRanges[i].UseMin;
+  end;
+end;
+
+{ Activates the live view mode. Because the Range of the y axes can be changed
+  their current Range is stored before activating, and restored after
+  deactivating the mode. }
 procedure TChartLiveView.SetActive(const AValue: Boolean);
 begin
   if FActive = AValue then exit;
 
   FActive := AValue;
+  if FChart <> nil then
+  begin
+    if FActive then
+      StoreAxisRanges
+    else
+      RestoreAxisRanges;
+  end;
+
   FullExtentChanged(nil);
 end;
 
+{ Attaches the chart on which the liveview operates. Installs a "listener"
+  object so that the liveview can be notified of a change in the chart's full
+  extent when a new data point has been added (method FullExtentChanged). }
 procedure TChartLiveView.SetChart(const AValue: TChart);
 begin
   if FChart = AValue then exit;
@@ -77,6 +144,7 @@ begin
   FChart := AValue;
   if FChart <> nil then
     FChart.FullExtentBroadcaster.Subscribe(FListener);
+  StoreAxisRanges;
   FullExtentChanged(Self);
 end;
 
@@ -84,30 +152,54 @@ procedure TChartLiveview.SetExtentY(const AValue: TChartLiveViewExtentY);
 begin
   if FExtentY = AValue then exit;
   FExtentY := AValue;
+  RestoreAxisRanges;
   FullExtentChanged(nil);
 end;
 
 procedure TChartLiveView.SetViewportSize(const AValue: Double);
 begin
   if FViewportSize = AValue then exit;
-
   FViewportSize := AValue;
   FullExtentChanged(nil);
 end;
 
+procedure TChartLiveView.StoreAxisRanges;
+var
+  i: Integer;
+  ax: TChartAxis;
+begin
+  SetLength(FAxisRanges, FChart.AxisList.Count);
+  for i := 0 to FChart.AxisList.Count-1 do
+  begin
+    ax := FChart.AxisList[i];
+    FAxisRanges[i].Max := ax.Range.Max;
+    FAxisRanges[i].Min := ax.Range.Min;
+    FAxisRanges[i].UseMax := ax.Range.UseMax;
+    FAxisRanges[i].UseMin := ax.Range.UseMin;
+  end;
+end;
+
+{ "Workhorse" method of the component. It calculates the logical extent and
+  the axis ranges needed to display only the recent data values in the
+  given viewport. }
 procedure TChartLiveView.UpdateViewport;
 var
-  fext, lext: TDoubleRect;
+  fext, lext: TDoubleRect;    // "full extent", "logical extent" variables
   w: double;
-  i: Integer;
+  i, j: Integer;
   ymin, ymax: Double;
+  ygmin, ygmax: Double;
+  ser: TChartSeries;
+  ax: TChartAxis;
 begin
   if not FChart.ScalingValid then
     exit;
 
+  if Length(FAxisRanges) = 0 then
+    StoreAxisRanges;
+
   fext := FChart.GetFullExtent();
   lext := FChart.LogicalExtent;
-  w := lext.b.x - lext.a.x;
   if FViewportSize = 0 then
     w := lext.b.x - lext.a.x
   else
@@ -119,19 +211,6 @@ begin
     lext.b.x := lext.a.x + w;
   end;
   case FExtentY of
-    lveAuto:
-      begin
-        ymin := Infinity;
-        ymax := -Infinity;
-        for i := 0 to FChart.SeriesCount-1 do
-          if FChart.Series[i] is TChartSeries then
-            TChartSeries(FChart.Series[i]).FindYRange(lext.a.x, lext.b.x, ymin, ymax);
-        if (ymin <> Infinity) and (ymax <> -Infinity) then
-        begin
-          lext.a.y := ymin;
-          lext.b.y := ymax;
-        end;
-      end;
     lveFull:
       begin
         lext.a.y := fext.a.y;
@@ -139,6 +218,57 @@ begin
       end;
     lveLogical:
       ;
+    lveAuto,
+    lveMultiAxisRange:
+      begin
+        lext.a.y := Infinity;
+        lext.b.y := -Infinity;
+        for i := 0 to FChart.AxisList.Count-1 do
+        begin
+          ax := FChart.AxisList[i];
+          // we only support scrolling along x, i.e. ax must be a y axis.
+          if not (ax.Alignment in [calLeft, calRight]) then
+            Continue;
+          ymin := Infinity;
+          ymax := -Infinity;
+          for j := 0 to FChart.SeriesCount-1 do
+            if FChart.Series[j] is TChartSeries then
+            begin
+              ser := TChartSeries(FChart.Series[j]);
+              if (not ser.Active) or (ser.GetAxisY <> ax) or ser.IsRotated then
+                continue;
+              ser.FindYRange(lext.a.x, lext.b.x, ymin, ymax);
+            end;
+          if (ymin = Infinity) then
+          begin
+            ymin := -1;
+            ymax := +1;
+          end else
+          if (ymin = ymax) then
+          begin
+            if ymin = 0 then
+            begin
+              ymin := -1;
+              ymax := +1;
+            end else
+            begin
+              ymin := abs(ymin) * 0.9;
+              ymax := abs(ymax) * 1.1;
+            end;
+          end;
+          ax.Range.Min := ymin;
+          ax.Range.Max := ymax;
+          if (FExtentY = lveMultiAxisRange) then
+          begin
+            if FAxisRanges[i].UseMin then ax.Range.Min := FAxisRanges[i].Min;
+            if FAxisRanges[i].UseMax then ax.Range.Max := FAxisRanges[i].Max;
+          end;
+          ax.Range.UseMin := true;
+          ax.Range.UseMax := true;
+          lext.a.y := Min(lext.a.y, ax.GetTransform.AxisToGraph(ymin));
+          lext.b.y := Max(lext.b.y, ax.GetTransform.AxisToGraph(ymax));
+        end;  // for i
+      end;
   end;
   FChart.LogicalExtent := lext;
 end;
diff --git a/components/tachart/tacustomseries.pas b/components/tachart/tacustomseries.pas
index e006c81c03..b9bd90b4f9 100644
--- a/components/tachart/tacustomseries.pas
+++ b/components/tachart/tacustomseries.pas
@@ -441,13 +441,17 @@ function TCustomChartSeries.GetAxisBounds(AAxis: TChartAxis;
   out AMin, AMax: Double): Boolean;
 var
   ex: TDoubleRect;
+  axIndexX, axIndexY: Integer;
 begin
-  if (AAxis.Index = AxisIndexX) or (AAxis.Index = AxisIndexY) then begin
+  axIndexX := GetAxisX.Index;
+  axIndexY := GetAxisY.Index;
+
+  if (AAxis.Index = axIndexX) or (AAxis.Index = axIndexY) then begin
     ex := EmptyExtent;
     GetBounds(ex);
     with ex do begin
-      UpdateBoundsByAxisRange(FChart.AxisList, AxisIndexX, a.X, b.X);
-      UpdateBoundsByAxisRange(FChart.AxisList, AxisIndexY, a.Y, b.Y);
+      UpdateBoundsByAxisRange(FChart.AxisList, axIndexX, a.X, b.X);
+      UpdateBoundsByAxisRange(FChart.AxisList, axIndexY, a.Y, b.Y);
       if IsRotated then begin
         Exchange(a.X, a.Y);
         Exchange(b.X, b.Y);
diff --git a/components/tachart/tagraph.pas b/components/tachart/tagraph.pas
index ab77eaab67..59992d38fb 100644
--- a/components/tachart/tagraph.pas
+++ b/components/tachart/tagraph.pas
@@ -352,6 +352,7 @@ type
     procedure Draw(ADrawer: IChartDrawer; const ARect: TRect);
     procedure DrawLegendOn(ACanvas: TCanvas; var ARect: TRect);
     procedure EnableRedrawing;
+    procedure GetAllSeriesAxisLimits(AAxis: TChartAxis; out AMin, AMax: Double);
     function GetFullExtent: TDoubleRect;
     function GetLegendItems(AIncludeHidden: Boolean = false): TChartLegendItems;
     procedure Notify(ACommand: Integer; AParam1, AParam2: Pointer; var AData); override;
@@ -1140,6 +1141,15 @@ begin
   AClass := nil;
 end;
 
+procedure TChart.GetAllSeriesAxisLimits(AAxis: TChartAxis; out AMin, AMax: Double);
+var
+  interval: TDoubleInterval;
+begin
+  interval := GetAxisBounds(AAxis);
+  AMin := interval.FStart;
+  AMax := interval.FEnd;
+end;
+
 function TChart.GetAxisBounds(AAxis: TChartAxis): TDoubleInterval;
 var
   s: TBasicChartSeries;
diff --git a/components/tachart/tatextelements.pas b/components/tachart/tatextelements.pas
index 2410703923..600f9ceb3a 100644
--- a/components/tachart/tatextelements.pas
+++ b/components/tachart/tatextelements.pas
@@ -365,7 +365,8 @@ begin
     ADrawer.ClippingStop;
 
   DrawLink(ADrawer, ADataPoint, ALabelCenter);
-  ADrawer.Brush := GetLabelBrush;
+  with GetLabelBrush do
+    ADrawer.SetBrushParams(Style, ColorToRGB(Color));
   if IsMarginRequired then begin
     if GetFrame.Visible then
       ADrawer.Pen := GetFrame
diff --git a/components/tachart/tatypes.pas b/components/tachart/tatypes.pas
index ec9d1b86ef..082c815b08 100644
--- a/components/tachart/tatypes.pas
+++ b/components/tachart/tatypes.pas
@@ -751,6 +751,7 @@ begin
   diag := -ADrawer.Scale(Round(Sqrt(Sqr(Length) + Sqr(Width))));
   pt1 := AEndPos + RotatePointX(diag, AAngle - da)*sgn;
   pt2 := AEndPos + RotatePointX(diag, AAngle + da)*sgn;
+  ADrawer.SetPenParams(psSolid, FPColorToTColor(APen.FPColor), APen.Width);
   if BaseLength > 0 then begin
     ptBase := AEndPos + RotatePointX(-ADrawer.Scale(BaseLength), AAngle)*sgn;
     ADrawer.SetBrushParams(bsSolid, FPColorToChartColor(APen.FPColor));