vtkTextRenderer.h

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

  Program:   Visualization Toolkit
  Module:    vtkTextRenderer.h

  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 vtkTextRenderer_h
#define vtkTextRenderer_h

#include "vtkRenderingCoreModule.h" // For export macro
#include "vtkObject.h"
#include "vtkTuple.h"  // For metrics struct
#include "vtkVector.h" // For metrics struct

class vtkImageData;
class vtkPath;
class vtkStdString;
class vtkUnicodeString;
class vtkTextProperty;

namespace vtksys {
class RegularExpression;
}

class VTKRENDERINGCORE_EXPORT vtkTextRendererCleanup
{
public:
  vtkTextRendererCleanup();
  ~vtkTextRendererCleanup();

private:
  vtkTextRendererCleanup(const vtkTextRendererCleanup& other) = delete;
  vtkTextRendererCleanup& operator=(const vtkTextRendererCleanup& rhs) = delete;
};

class VTKRENDERINGCORE_EXPORT vtkTextRenderer: public vtkObject
{
public:
  struct Metrics
  {
    Metrics()
      : BoundingBox(0),
        TopLeft(0), TopRight(0), BottomLeft(0), BottomRight(0),
        Ascent(0), Descent(0)
    {
    }

    vtkTuple<int, 4> BoundingBox;


    vtkVector2i TopLeft;
    vtkVector2i TopRight;
    vtkVector2i BottomLeft;
    vtkVector2i BottomRight;

    vtkVector2i Ascent;
    vtkVector2i Descent;
  };

  vtkTypeMacro(vtkTextRenderer, vtkObject)
  void PrintSelf(ostream &os, vtkIndent indent) override;

  static vtkTextRenderer *New();

  static vtkTextRenderer* GetInstance();

  enum Backend
  {
    Default = -1,
    Detect = 0,
    FreeType,
    MathText,

    UserBackend = 16
  };


  vtkSetMacro(DefaultBackend, int)
  vtkGetMacro(DefaultBackend, int)


  virtual int DetectBackend(const vtkStdString &str);
  virtual int DetectBackend(const vtkUnicodeString &str);

  virtual bool FreeTypeIsSupported() { return false; }
  virtual bool MathTextIsSupported() { return false; }


  bool GetBoundingBox(vtkTextProperty *tprop, const vtkStdString &str,
                      int bbox[4], int dpi, int backend = Default)
  {
    return this->GetBoundingBoxInternal(tprop, str, bbox, dpi, backend);
  }
  bool GetBoundingBox(vtkTextProperty *tprop, const vtkUnicodeString &str,
                      int bbox[4], int dpi, int backend = Default)
  {
    return this->GetBoundingBoxInternal(tprop, str, bbox, dpi, backend);
  }



  bool GetMetrics(vtkTextProperty *tprop, const vtkStdString &str,
                  Metrics &metrics, int dpi, int backend = Default)
  {
    return this->GetMetricsInternal(tprop, str, metrics, dpi, backend);
  }
  bool GetMetrics(vtkTextProperty *tprop, const vtkUnicodeString &str,
                  Metrics &metrics, int dpi, int backend = Default)
  {
    return this->GetMetricsInternal(tprop, str, metrics, dpi, backend);
  }


  bool RenderString(vtkTextProperty *tprop, const vtkStdString &str,
                    vtkImageData *data, int textDims[2], int dpi,
                    int backend = Default)
  {
    return this->RenderStringInternal(tprop, str, data, textDims, dpi, backend);
  }
  bool RenderString(vtkTextProperty *tprop, const vtkUnicodeString &str,
                    vtkImageData *data, int textDims[2], int dpi,
                    int backend = Default)
  {
    return this->RenderStringInternal(tprop, str, data, textDims, dpi, backend);
  }


  int GetConstrainedFontSize(const vtkStdString &str, vtkTextProperty *tprop,
                             int targetWidth, int targetHeight, int dpi,
                             int backend = Default)
  {
    return this->GetConstrainedFontSizeInternal(str, tprop, targetWidth,
                                                targetHeight, dpi, backend);
  }
  int GetConstrainedFontSize(const vtkUnicodeString &str, vtkTextProperty *tprop,
                             int targetWidth, int targetHeight, int dpi,
                             int backend = Default)
  {
    return this->GetConstrainedFontSizeInternal(str, tprop, targetWidth,
                                                targetHeight, dpi, backend);
  }


  bool StringToPath(vtkTextProperty *tprop, const vtkStdString &str,
                    vtkPath *path, int dpi, int backend = Default)
  {
    return this->StringToPathInternal(tprop, str, path, dpi, backend);
  }
  bool StringToPath(vtkTextProperty *tprop, const vtkUnicodeString &str,
                    vtkPath *path, int dpi, int backend = Default)
  {
    return this->StringToPathInternal(tprop, str, path, dpi, backend);
  }

  void SetScaleToPowerOfTwo(bool scale)
  {
    this->SetScaleToPowerOfTwoInternal(scale);
  }

  friend class vtkTextRendererCleanup;

protected:
  vtkTextRenderer();
  ~vtkTextRenderer() override;


  virtual bool GetBoundingBoxInternal(vtkTextProperty *tprop,
                                      const vtkStdString &str,
                                      int bbox[4], int dpi, int backend) = 0;
  virtual bool GetBoundingBoxInternal(vtkTextProperty *tprop,
                                      const vtkUnicodeString &str,
                                      int bbox[4], int dpi, int backend) = 0;
  virtual bool GetMetricsInternal(vtkTextProperty *tprop,
                                  const vtkStdString &str,
                                  Metrics &metrics, int dpi, int backend) = 0;
  virtual bool GetMetricsInternal(vtkTextProperty *tprop,
                                  const vtkUnicodeString &str,
                                  Metrics &metrics, int dpi, int backend) = 0;
  virtual bool RenderStringInternal(vtkTextProperty *tprop,
                                    const vtkStdString &str,
                                    vtkImageData *data, int textDims[2],
                                    int dpi, int backend) = 0;
  virtual bool RenderStringInternal(vtkTextProperty *tprop,
                                    const vtkUnicodeString &str,
                                    vtkImageData *data, int textDims[2],
                                    int dpi, int backend) = 0;
  virtual int GetConstrainedFontSizeInternal(const vtkStdString &str,
                                             vtkTextProperty *tprop,
                                             int targetWidth, int targetHeight,
                                             int dpi, int backend) = 0;
  virtual int GetConstrainedFontSizeInternal(const vtkUnicodeString &str,
                                             vtkTextProperty *tprop,
                                             int targetWidth, int targetHeight,
                                             int dpi, int backend) = 0;
  virtual bool StringToPathInternal(vtkTextProperty *tprop,
                                    const vtkStdString &str, vtkPath *path,
                                    int dpi, int backend) = 0;
  virtual bool StringToPathInternal(vtkTextProperty *tprop,
                                    const vtkUnicodeString &str, vtkPath *path,
                                    int dpi, int backend) = 0;
  virtual void SetScaleToPowerOfTwoInternal(bool scale) = 0;

  static void SetInstance(vtkTextRenderer *instance);


  static vtkTextRenderer *Instance;
  static vtkTextRendererCleanup Cleanup;

  vtksys::RegularExpression *MathTextRegExp;
  vtksys::RegularExpression *MathTextRegExp2;


  virtual void CleanUpFreeTypeEscapes(vtkStdString &str);
  virtual void CleanUpFreeTypeEscapes(vtkUnicodeString &str);

  int DefaultBackend;

private:
  vtkTextRenderer(const vtkTextRenderer &) = delete;
  void operator=(const vtkTextRenderer &) = delete;
};

#endif //vtkTextRenderer_h