gecko-dev/gfx/public/nsDeviceContext.h

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 * 1.1 (the "License"); you may not use this file except in compliance with
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 * for the specific language governing rights and limitations under the
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 * The Original Code is mozilla.org code.
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 * The Initial Developer of the Original Code is
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 * Portions created by the Initial Developer are Copyright (C) 1998
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 * Contributor(s):
 *   Roland Mainz <Roland.Mainz@informatik.med.uni-giessen.de>
 *
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#ifndef nsDeviceContext_h___
#define nsDeviceContext_h___

#include "nsIDeviceContext.h"
#include "nsIDeviceContextSpec.h"
#include "nsCOMPtr.h"
#include "nsIAtom.h"
#include "nsVoidArray.h"
#include "nsIObserver.h"
#include "nsIObserverService.h"
#include "nsWeakReference.h"
#include "gfxCore.h"

class nsIImageRequest;
class nsHashtable;

class NS_GFX nsFontCache
{
public:
  nsFontCache();
  virtual ~nsFontCache();

  virtual nsresult Init(nsIDeviceContext* aContext);
  virtual nsresult GetDeviceContext(nsIDeviceContext *&aContext) const;
  virtual nsresult GetMetricsFor(const nsFont& aFont, nsIAtom* aLangGroup,
                                 nsIFontMetrics *&aMetrics);

  nsresult   FontMetricsDeleted(const nsIFontMetrics* aFontMetrics);
  nsresult   Compact();
  nsresult   Flush();
  /* printer device context classes may create their own
   * subclasses of nsFontCache (and override this method) and override 
   * DeviceContextImpl::CreateFontCache (see bug 81311).
   */
  virtual nsresult CreateFontMetricsInstance(nsIFontMetrics** fm);
  
protected:
  nsVoidArray      mFontMetrics;
  nsIDeviceContext *mContext; // we do not addref this since
                              // ownership is implied. MMP.
};

#undef  IMETHOD_VISIBILITY
#define IMETHOD_VISIBILITY NS_VISIBILITY_DEFAULT

class NS_GFX DeviceContextImpl : public nsIDeviceContext,
                                 public nsIObserver,
                                 public nsSupportsWeakReference
{
public:
  DeviceContextImpl();

  NS_DECL_ISUPPORTS
  NS_DECL_NSIOBSERVER

  NS_IMETHOD  Init(nsNativeWidget aWidget);

  NS_IMETHOD  CreateRenderingContext(nsIView *aView, nsIRenderingContext *&aContext);
  NS_IMETHOD  CreateRenderingContext(nsIWidget *aWidget, nsIRenderingContext *&aContext);
  NS_IMETHOD  CreateRenderingContext(nsIRenderingContext *&aContext){return NS_ERROR_NOT_IMPLEMENTED;}
  NS_IMETHOD  CreateRenderingContext(nsIDrawingSurface* aSurface, nsIRenderingContext *&aContext);
  NS_IMETHOD  CreateRenderingContextInstance(nsIRenderingContext *&aContext);

  NS_IMETHOD  GetCanonicalPixelScale(float &aScale) const;
  NS_IMETHOD  SetCanonicalPixelScale(float aScale);

  NS_IMETHOD  GetMetricsFor(const nsFont& aFont, nsIAtom* aLangGroup,
                            nsIFontMetrics*& aMetrics);
  NS_IMETHOD  GetMetricsFor(const nsFont& aFont, nsIFontMetrics*& aMetrics);

  NS_IMETHOD  SetZoom(float aZoom);
  NS_IMETHOD  GetZoom(float &aZoom) const;

  NS_IMETHOD FirstExistingFont(const nsFont& aFont, nsString& aFaceName);

  NS_IMETHOD GetLocalFontName(const nsString& aFaceName, nsString& aLocalName,
                              PRBool& aAliased);

  NS_IMETHOD CreateFontCache();
  NS_IMETHOD FontMetricsDeleted(const nsIFontMetrics* aFontMetrics);
  NS_IMETHOD FlushFontCache(void);

  NS_IMETHOD GetDepth(PRUint32& aDepth);

  NS_IMETHOD GetPaletteInfo(nsPaletteInfo& aPaletteInfo);

  NS_IMETHOD PrepareDocument(PRUnichar * aTitle, 
                             PRUnichar*  aPrintToFileName) { return NS_OK; }
  NS_IMETHOD AbortDocument(void) { return NS_OK; }

#ifdef NS_PRINT_PREVIEW
  NS_IMETHOD SetAltDevice(nsIDeviceContext* aAltDC);
  NS_IMETHOD GetAltDevice(nsIDeviceContext** aAltDC) { *aAltDC = mAltDC.get(); NS_IF_ADDREF(*aAltDC); return NS_OK;}
  NS_IMETHOD SetUseAltDC(PRUint8 aValue, PRBool aOn);
#endif

  NS_IMETHOD PrepareNativeWidget(nsIWidget *aWidget, void **aOut);
  NS_IMETHOD ClearCachedSystemFonts();

private:
  /* Helper methods for |CreateRenderingContext|&co. */
  nsresult InitRenderingContext(nsIRenderingContext *aContext, nsIWidget *aWindow);
  nsresult InitRenderingContext(nsIRenderingContext *aContext, nsIDrawingSurface* aSurface);

protected:
  virtual ~DeviceContextImpl();

  void CommonInit(void);
  nsresult CreateIconILGroupContext();
  virtual nsresult CreateFontAliasTable();
  nsresult AliasFont(const nsString& aFont, 
                     const nsString& aAlias, const nsString& aAltAlias,
                     PRBool aForceAlias);
  void GetLocaleLangGroup(void);

  nsFontCache       *mFontCache;
  nsCOMPtr<nsIAtom> mLocaleLangGroup; // XXX temp fix for performance bug - erik
  float             mZoom;
  nsHashtable*      mFontAliasTable;
  float             mCPixelScale;

#ifdef NS_PRINT_PREVIEW
  nsCOMPtr<nsIDeviceContext> mAltDC;
  PRUint8           mUseAltDC;
#endif

public:
  nsNativeWidget    mWidget;
#ifdef NS_DEBUG
  PRBool            mInitialized;
#endif
};

#undef  IMETHOD_VISIBILITY
#define IMETHOD_VISIBILITY NS_VISIBILITY_HIDDEN

#endif /* nsDeviceContext_h___ */