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 * 
 * 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
 * 
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
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#ifndef _SD_ACCESSIBILITY_ACCESSIBLE_VIEW_FORWARDER_HXX
#define _SD_ACCESSIBILITY_ACCESSIBLE_VIEW_FORWARDER_HXX

#include <svx/IAccessibleViewForwarder.hxx>

class SdrPaintView;
class OutputDevice;

namespace accessibility {


/**	<p>This class provides the means to transform between internal coordinates
    and screen coordinates without giving direct access to the underlying
    view.  It represents a certain window.  A call to
    <method>GetVisArea</method> returns the corresponding visible
    rectangle.</p>

    @attention
        Note, that modifications of the underlying view that lead to
        different transformations between internal and screen coordinates or
        change the validity of the forwarder have to be signaled seperately.
*/
class AccessibleViewForwarder
    :	public IAccessibleViewForwarder
{
public:
    //=====  internal  ========================================================

    AccessibleViewForwarder (SdrPaintView* pView, OutputDevice& rDevice);

	virtual ~AccessibleViewForwarder (void);
    
    //=====  IAccessibleViewforwarder  ========================================

    /** This method informs you about the state of the forwarder.  Do not
        use it when the returned value is <false/>.

    	@return
            Return <true/> if the view forwarder is valid and <false/> else.
     */
	virtual sal_Bool IsValid (void) const;

    /** Returns the area of the underlying document that is visible in the
    * corresponding window.

    	@return 
            The rectangle of the visible part of the document.
     */
    virtual Rectangle GetVisibleArea() const;

    /** Transform the specified point from internal coordinates to an
        absolute screen position.

    	@param rPoint
            Point in internal coordinates.

        @return 
            The same point but in screen coordinates relative to the upper
            left corner of the (current) screen.
     */
    virtual Point LogicToPixel (const Point& rPoint) const;

    /** Transform the specified size from internal coordinates to a screen
    * position.

    	@param rSize
            Size in internal coordinates.

        @return 
            The same size but in screen coordinates.
     */
    virtual Size LogicToPixel (const Size& rSize) const;

    /** Transform the specified point from absolute screen coordinates to
        internal coordinates.

    	@param rPoint
            Point in screen coordinates relative to the upper left corner of
            the (current) screen.

        @return 
            The same point but in internal coordinates.
     */
    virtual Point PixelToLogic (const Point& rPoint) const;

    /** Transform the specified Size from screen coordinates to internal
        coordinates.

    	@param rSize
            Size in screen coordinates.

        @return 
            The same size but in internal coordinates.
     */
    virtual Size PixelToLogic (const Size& rSize) const;

protected:
    SdrPaintView* mpView;
    sal_uInt16 mnWindowId;
    OutputDevice& mrDevice;

private:
    AccessibleViewForwarder (AccessibleViewForwarder&);
    AccessibleViewForwarder& operator= (AccessibleViewForwarder&);
};

} // end of namespace accessibility

#endif