text: 
  /*=========================================================================*\
  
      Copyright (c) Microsoft Corporation.  All rights reserved.
  
      File: D2D1_2Helper.h
  
      Module Name: D2D
  
      Description: Helper files over the D2D interfaces and APIs.
  
  \*=========================================================================*/
  
  #ifdef _MSC_VER
  #pragma once
  #endif  // _MSC_VER
  
  #ifndef _D2D1_2HELPER_H_
  #define _D2D1_2HELPER_H_
  
  #if NTDDI_VERSION >= NTDDI_WINBLUE
  
  #ifndef _D2D1_2_H_
  #include <d2d1_2.h>
  #endif // #ifndef _D2D1_2_H_
  
  #ifndef D2D_USE_C_DEFINITIONS
  
  #include <winapifamily.h>
  
  #pragma region Application Family
  #if WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_APP)
  
  namespace D2D1
  {
      COM_DECLSPEC_NOTHROW
      D2D1FORCEINLINE
      FLOAT
      ComputeFlatteningTolerance(
          _In_ CONST D2D1_MATRIX_3X2_F &matrix,
          FLOAT dpiX = 96.0f,
          FLOAT dpiY = 96.0f,
          FLOAT maxZoomFactor = 1.0f
          )
      {
          D2D1_MATRIX_3X2_F dpiDependentTransform =
              matrix * D2D1::Matrix3x2F::Scale(dpiX / 96.0f, dpiY / 96.0f);
   
          FLOAT absMaxZoomFactor = (maxZoomFactor > 0) ? maxZoomFactor : -maxZoomFactor;
  
          return D2D1_DEFAULT_FLATTENING_TOLERANCE / 
              (absMaxZoomFactor * D2D1ComputeMaximumScaleFactor(&dpiDependentTransform));
      }
  
  } // namespace D2D1
  
  #endif /* WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_APP) */
  #pragma endregion
  
  #endif // #ifndef D2D_USE_C_DEFINITIONS
  
  #endif // #if NTDDI_VERSION >= NTDDI_WINBLUE
  
  #endif // #ifndef _D2D1_HELPER_H_
  
  