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diff --git a/chart2/source/view/inc/ScaleAutomatism.hxx b/chart2/source/view/inc/ScaleAutomatism.hxx
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+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+#pragma once
+
+#include <com/sun/star/chart2/ScaleData.hpp>
+
+#include <tools/date.hxx>
+
+namespace chart { struct ExplicitIncrementData; }
+namespace chart { struct ExplicitScaleData; }
+
+namespace chart
+{
+
+/** This class implements the calculation of automatic axis limits.
+ *
+ *  This class is used for calculating axis scales and increments in the form
+ *  of instances of `ExplicitScaleData` and `ExplicitIncrementData` classes.
+ *  When a `ScaleAutomatism` instance is created a `ScaleData` object is passed
+ *  to the constructor. Objects of `ScaleData` type are initialized by
+ *  the `createCoordinateSystem` method of some chart type (e.g.
+ *  the `PieChartType` class) and belong to some `Axis` object, they can be
+ *  accessed through the `XAxis` interface (`XAxis::getScaleData`).
+ */
+class ScaleAutomatism
+{
+public:
+    explicit            ScaleAutomatism(
+                            const css::chart2::ScaleData& rSourceScale, const Date& rNullDate );
+
+    /** Expands own value range with the passed minimum and maximum.
+     *
+     *  It allows to set up the `m_fValueMinimum` and the `m_fValueMaximum`
+     *  parameters which are used by the `calculateExplicitScaleAndIncrement`
+     *  method for initializing the `Minimum` and `Maximum` properties of the
+     *  explicit scale when the same properties of the `ScaleData` object are
+     *  undefined (that is empty `uno::Any` objects).
+     */
+    void                expandValueRange( double fMinimum, double fMaximum );
+    void                resetValueRange();
+
+    /** Sets additional auto scaling options.
+        @param bExpandBorderToIncrementRhythm  If true, expands automatic
+            borders to the fixed or calculated increment rhythm.
+        @param bExpandIfValuesCloseToBorder  If true, expands automatic borders
+            if values are too close (closer than 1/21 of visible area).
+        @param bExpandWideValuesToZero  If true, expands automatic border to
+            zero, if source values are positive only or negative only, and if
+            the absolute values are wide spread (at least one value is less
+            than 5/6 of absolute maximum), or if all values are equal.
+        @param bExpandNarrowValuesTowardZero  If true, expands automatic border
+            toward zero (50% of the visible range), if source values are
+            positive only or negative only, and if the absolute values are
+            close to the absolute maximum (no value is less than 5/6 of
+            absolute maximum). */
+    void                setAutoScalingOptions(
+                            bool bExpandBorderToIncrementRhythm,
+                            bool bExpandIfValuesCloseToBorder,
+                            bool bExpandWideValuesToZero,
+                            bool bExpandNarrowValuesTowardZero );
+
+    /** Sets the maximum allowed number of automatic main increments.
+        @descr  The number of main increments may be limited e.g. by the length
+                of the axis and the font size of the axis caption text. */
+    void                setMaximumAutoMainIncrementCount( sal_Int32 nMaximumAutoMainIncrementCount );
+
+    /** Sets the time resolution to be used in case it is not set explicitly within the scale
+    */
+    void setAutomaticTimeResolution( sal_Int32 nTimeResolution );
+
+    /** Fills the passed scale data and increment data according to the own settings.
+     *
+     *  It performs the initialization of the passed explicit scale and
+     *  explicit increment parameters, mainly the initialization is achieved by
+     *  using the `ScaleData` object as data source. However other parameters
+     *  which affect the behavior of this method can be set through
+     *  the `setAutoScalingOptions` and the `expandValueRange` methods.
+     */
+    void                calculateExplicitScaleAndIncrement(
+                            ExplicitScaleData& rExplicitScale,
+                            ExplicitIncrementData& rExplicitIncrement ) const;
+
+    const css::chart2::ScaleData& getScale() const { return m_aSourceScale;}
+    const Date& getNullDate() const { return m_aNullDate;}
+
+private:
+    /** Fills the passed scale data and increment data for category scaling. */
+    void                calculateExplicitIncrementAndScaleForCategory(
+                            ExplicitScaleData& rExplicitScale,
+                            ExplicitIncrementData& rExplicitIncrement,
+                            bool bAutoMinimum, bool bAutoMaximum ) const;
+
+    /** Fills the passed scale data and increment data for logarithmic scaling. */
+    void                calculateExplicitIncrementAndScaleForLogarithmic(
+                            ExplicitScaleData& rExplicitScale,
+                            ExplicitIncrementData& rExplicitIncrement,
+                            bool bAutoMinimum, bool bAutoMaximum ) const;
+
+    /** Fills the passed scale data and increment data for linear scaling. */
+    void                calculateExplicitIncrementAndScaleForLinear(
+                            ExplicitScaleData& rExplicitScale,
+                            ExplicitIncrementData& rExplicitIncrement,
+                            bool bAutoMinimum, bool bAutoMaximum ) const;
+
+    /** Fills the passed scale data and increment data for date-time axis. */
+    void                calculateExplicitIncrementAndScaleForDateTimeAxis(
+                            ExplicitScaleData& rExplicitScale,
+                            ExplicitIncrementData& rExplicitIncrement,
+                            bool bAutoMinimum, bool bAutoMaximum ) const;
+
+private:
+    css::chart2::ScaleData             m_aSourceScale;
+
+    double              m_fValueMinimum;                    /// Minimum of all source values.
+    double              m_fValueMaximum;                    /// Maximum of all source values.
+    sal_Int32           m_nMaximumAutoMainIncrementCount;   /// Maximum number of automatic main increments.
+    bool                m_bExpandBorderToIncrementRhythm;   /// true = Expand to main increments.
+    bool                m_bExpandIfValuesCloseToBorder;     /// true = Expand if values are too close to the borders.
+    bool                m_bExpandWideValuesToZero;          /// true = Expand wide spread values to zero.
+    bool                m_bExpandNarrowValuesTowardZero;    /// true = Expand narrow range toward zero (add half of range).
+    sal_Int32           m_nTimeResolution;// a constant out of css::chart::TimeUnit
+
+    Date                m_aNullDate;
+};
+
+} //namespace chart
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */