pdfium 矩阵

// Transform |page_object| by the given matrix.

// page_object - handle to a page object.

// a - matrix value.

// b - matrix value.

// c - matrix value.

// d - matrix value.

// e - matrix value.

// f - matrix value.

// The matrix is composed as:

// |a c e|

// |b d f|

// and can be used to scale, rotate, shear and translate the |page_object|.

DLLEXPORT void STDCALL FPDFPageObj_Transform(FPDF_PAGEOBJECT page_object,

double a,

double b,

double c,

double d,

double e,

double f);

DLLEXPORT void STDCALL FPDFPageObj_Transform(FPDF_PAGEOBJECT page_object,

double a,

double b,

double c,

double d,

double e,

double f) {

CPDF_PageObject* pPageObj = CPDFPageObjectFromFPDFPageObject(page_object);

if (!pPageObj)

return;

CFX_Matrix matrix((float)a, (float)b, (float)c, (float)d, (float)e, (float)f);

pPageObj->Transform(matrix);

}

class CPDF_PageObject : public CPDF_GraphicStates {
 public:
  enum Type {
    TEXT = 1,
    PATH,
    IMAGE,
    SHADING,
    FORM,
  };
 
  CPDF_PageObject();
  ~CPDF_PageObject() override;
 
  virtual Type GetType() const = 0;
  virtual void Transform(const CFX_Matrix& matrix) = 0;
  virtual bool IsText() const;
  virtual bool IsPath() const;
  virtual bool IsImage() const;
  virtual bool IsShading() const;
  virtual bool IsForm() const;
  virtual CPDF_TextObject* AsText();
  virtual const CPDF_TextObject* AsText() const;
  virtual CPDF_PathObject* AsPath();
  virtual const CPDF_PathObject* AsPath() const;
  virtual CPDF_ImageObject* AsImage();
  virtual const CPDF_ImageObject* AsImage() const;
  virtual CPDF_ShadingObject* AsShading();
  virtual const CPDF_ShadingObject* AsShading() const;
  virtual CPDF_FormObject* AsForm();
  virtual const CPDF_FormObject* AsForm() const;
 
  void SetDirty(bool value) { m_bDirty = value; }
  bool IsDirty() const { return m_bDirty; }
  void TransformClipPath(CFX_Matrix& matrix);
  void TransformGeneralState(CFX_Matrix& matrix);
 
  CFX_FloatRect GetRect() const {
    return CFX_FloatRect(m_Left, m_Bottom, m_Right, m_Top);
  }
  FX_RECT GetBBox(const CFX_Matrix* pMatrix) const;
 
  float m_Left;
  float m_Right;
  float m_Top;
  float m_Bottom;
  CPDF_ContentMark m_ContentMark;
 
 protected:
  void CopyData(const CPDF_PageObject* pSrcObject);
 
 private:
  CPDF_PageObject(const CPDF_PageObject& src) = delete;
  void operator=(const CPDF_PageObject& src) = delete;
 
  bool m_bDirty;
};