dox/Rendering/vtkFreeTypeUtilities.h

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/*=========================================================================

  Program:   Visualization Toolkit
  Module:    $RCSfile: vtkFreeTypeUtilities.h,v $

  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
  All rights reserved.
  See Copyright.txt or http://www.kitware.com/Copyright.htm for details.

     This software is distributed WITHOUT ANY WARRANTY; without even
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
     PURPOSE.  See the above copyright notice for more information.

=========================================================================*/
#ifndef __vtkFreeTypeUtilities_h
#define __vtkFreeTypeUtilities_h

#define VTK_FTFC_CACHE_CAPACITY 150

#include "vtkObject.h"

class vtkImageData;
class vtkTextProperty;

// FreeType

#include "vtk_freetype.h"  //since ft2build.h could be in the path
#include FT_FREETYPE_H
#include FT_GLYPH_H

#if (FREETYPE_MAJOR >2 ||(FREETYPE_MAJOR == 2 && ( FREETYPE_MINOR > 1 || (FREETYPE_MINOR == 1 && FREETYPE_PATCH >= 9))))
# include FT_CACHE_H
// This flag will be used to check if Caching support is to be compiled.
# define VTK_FREETYPE_CACHING_SUPPORTED
#endif

class FTFont;

//----------------------------------------------------------------------------
// Singleton cleanup

class VTK_RENDERING_EXPORT vtkFreeTypeUtilitiesCleanup
{
public:
  vtkFreeTypeUtilitiesCleanup();
  ~vtkFreeTypeUtilitiesCleanup();
};

//----------------------------------------------------------------------------
// Singleton font cache

class VTK_RENDERING_EXPORT vtkFreeTypeUtilities : public vtkObject
{
public:
  vtkTypeRevisionMacro(vtkFreeTypeUtilities, vtkObject);
  void PrintSelf(ostream& os, vtkIndent indent);

  static vtkFreeTypeUtilities *New();

  static vtkFreeTypeUtilities* GetInstance();

  static void SetInstance(vtkFreeTypeUtilities *instance);

  FT_Library* GetLibrary();


  vtkSetClampMacro(MaximumNumberOfFaces,unsigned int,1,VTK_UNSIGNED_INT_MAX);
  vtkGetMacro(MaximumNumberOfFaces, unsigned int);
  vtkSetClampMacro(MaximumNumberOfSizes,unsigned int,1,VTK_UNSIGNED_INT_MAX);
  vtkGetMacro(MaximumNumberOfSizes, unsigned int);
  vtkSetClampMacro(MaximumNumberOfBytes,unsigned long,1,VTK_UNSIGNED_LONG_MAX);
  vtkGetMacro(MaximumNumberOfBytes, unsigned long);



  int GetSize(vtkTextProperty *tprop, FT_Size *size);

  int GetFace(vtkTextProperty *tprop, FT_Face *face);

  int GetGlyphIndex(vtkTextProperty *tprop, char c, FT_UInt *gindex);


  enum 
  {
    GLYPH_REQUEST_DEFAULT = 0,
    GLYPH_REQUEST_BITMAP  = 1,
    GLYPH_REQUEST_OUTLINE = 2
  };
  //ETX
  int GetGlyph(vtkTextProperty *tprop, 
               char c, 
               FT_Glyph *glyph, 
               int request = GLYPH_REQUEST_DEFAULT);


  int GetBoundingBox(vtkTextProperty *tprop, const char *str, int bbox[4]);
  int IsBoundingBoxValid(int bbox[4]);


  int RenderString(vtkTextProperty *tprop, 
                   const char *str, 
                   vtkImageData *data);


  int RenderString(vtkTextProperty *tprop, 
                   const char *str, 
                   int x, int y, 
                   vtkImageData *data);


  void MapTextPropertyToId(vtkTextProperty *tprop, unsigned long *tprop_cache_id);
  void MapIdToTextProperty(unsigned long tprop_cache_id, vtkTextProperty *tprop);


  int GetSize(unsigned long tprop_cache_id, int font_size, FT_Size *size);
  int GetFace(unsigned long tprop_cache_id, FT_Face *face);
  int GetGlyphIndex(unsigned long tprop_cache_id, char c, FT_UInt *gindex);
  int GetGlyph(unsigned long tprop_cache_id, 
               int font_size, 
               FT_UInt gindex, 
               FT_Glyph *glyph, 
               int request = GLYPH_REQUEST_DEFAULT);


  void GetWidthHeightDescender(const char *str,
                               vtkTextProperty *tprop,
                               int *width,
                               int *height,
                               float *descender);


  void PrepareImageData(vtkImageData *data,
                        vtkTextProperty *tprop,
                        const char *str,
                        int *x, int *y);


  int GetConstrainedFontSize(const char *str, vtkTextProperty *tprop,
                             double orientation, int targetWidth,
                             int targetHeight);


  void JustifyLine(const char *str, vtkTextProperty *tprop,
                   int totalWidth, int *x, int *y);

  // Old Code
  // Cache entry

  struct Entry
  {
    vtkTextProperty *TextProperty;
    FTFont *Font;
    float LargestAscender;
    float LargestDescender;
  };

  vtkFreeTypeUtilities::Entry* GetFont(vtkTextProperty *tprop, 
                                       double override_color[3] = NULL);

protected:
  //Internal helper method called by RenderString
  int PopulateImageData(vtkTextProperty *tprop, const char *str,
                        int x, int y, vtkImageData *data, int use_shadow_color);
  vtkFreeTypeUtilities();
  virtual ~vtkFreeTypeUtilities();

private:
  vtkFreeTypeUtilities(const vtkFreeTypeUtilities&);  // Not implemented.
  void operator=(const vtkFreeTypeUtilities&);  // Not implemented.

  // The singleton instance and the singleton cleanup instance

  static vtkFreeTypeUtilities* Instance;
  static vtkFreeTypeUtilitiesCleanup Cleanup;

  // The cache manager, image cache and charmap cache

#ifdef VTK_FREETYPE_CACHING_SUPPORTED 
  FTC_Manager *CacheManager;
  FTC_ImageCache *ImageCache;
  FTC_CMapCache  *CMapCache;


  FTC_Manager* GetCacheManager();
  FTC_ImageCache* GetImageCache();
  FTC_CMapCache* GetCMapCache();
#endif

  unsigned int MaximumNumberOfFaces;
  unsigned int MaximumNumberOfSizes;
  unsigned long MaximumNumberOfBytes;

  void InitializeCacheManager();
  void ReleaseCacheManager();

  // Old Code

  void PrintEntry(int i, char *msg = 0);
  void ReleaseEntry(int i);

  void InitializeCache();
  void ReleaseCache();

  Entry *Entries[VTK_FTFC_CACHE_CAPACITY];
  int NumberOfEntries;
};

#endif

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