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  /** @file postprocess.h
   *  @brief Definitions for import post processing steps
   */
  #pragma once
  #ifndef AI_POSTPROCESS_H_INC
  #define AI_POSTPROCESS_H_INC
  
  #include <assimp/types.h>
  
  #ifdef __GNUC__
  #   pragma GCC system_header
  #endif
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  // -----------------------------------------------------------------------------------
  /** @enum  aiPostProcessSteps
   *  @brief Defines the flags for all possible post processing steps.
   *
   *  @note Some steps are influenced by properties set on the Assimp::Importer itself
   *
   *  @see Assimp::Importer::ReadFile()
   *  @see Assimp::Importer::SetPropertyInteger()
   *  @see aiImportFile
   *  @see aiImportFileEx
   */
  // -----------------------------------------------------------------------------------
  enum aiPostProcessSteps
  {
  
      // -------------------------------------------------------------------------
      /** <hr>Calculates the tangents and bitangents for the imported meshes.
       *
       * Does nothing if a mesh does not have normals. You might want this post
       * processing step to be executed if you plan to use tangent space calculations
       * such as normal mapping  applied to the meshes. There's an importer property,
       * <tt>#AI_CONFIG_PP_CT_MAX_SMOOTHING_ANGLE</tt>, which allows you to specify
       * a maximum smoothing angle for the algorithm. However, usually you'll
       * want to leave it at the default value.
       */
      aiProcess_CalcTangentSpace = 0x1,
  
      // -------------------------------------------------------------------------
      /** <hr>Identifies and joins identical vertex data sets within all
       *  imported meshes.
       *
       * After this step is run, each mesh contains unique vertices,
       * so a vertex may be used by multiple faces. You usually want
       * to use this post processing step. If your application deals with
       * indexed geometry, this step is compulsory or you'll just waste rendering
       * time. <b>If this flag is not specified</b>, no vertices are referenced by
       * more than one face and <b>no index buffer is required</b> for rendering.
       */
      aiProcess_JoinIdenticalVertices = 0x2,
  
      // -------------------------------------------------------------------------
      /** <hr>Converts all the imported data to a left-handed coordinate space.
       *
       * By default the data is returned in a right-handed coordinate space (which
       * OpenGL prefers). In this space, +X points to the right,
       * +Z points towards the viewer, and +Y points upwards. In the DirectX
       * coordinate space +X points to the right, +Y points upwards, and +Z points
       * away from the viewer.
       *
       * You'll probably want to consider this flag if you use Direct3D for
       * rendering. The #aiProcess_ConvertToLeftHanded flag supersedes this
       * setting and bundles all conversions typically required for D3D-based
       * applications.
       */
      aiProcess_MakeLeftHanded = 0x4,
  
      // -------------------------------------------------------------------------
      /** <hr>Triangulates all faces of all meshes.
       *
       * By default the imported mesh data might contain faces with more than 3
       * indices. For rendering you'll usually want all faces to be triangles.
       * This post processing step splits up faces with more than 3 indices into
       * triangles. Line and point primitives are *not* modified! If you want
       * 'triangles only' with no other kinds of primitives, try the following
       * solution:
       * <ul>
       * <li>Specify both #aiProcess_Triangulate and #aiProcess_SortByPType </li>
       * <li>Ignore all point and line meshes when you process assimp's output</li>
       * </ul>
       */
      aiProcess_Triangulate = 0x8,
  
      // -------------------------------------------------------------------------
      /** <hr>Removes some parts of the data structure (animations, materials,
       *  light sources, cameras, textures, vertex components).
       *
       * The  components to be removed are specified in a separate
       * importer property, <tt>#AI_CONFIG_PP_RVC_FLAGS</tt>. This is quite useful
       * if you don't need all parts of the output structure. Vertex colors
       * are rarely used today for example... Calling this step to remove unneeded
       * data from the pipeline as early as possible results in increased
       * performance and a more optimized output data structure.
       * This step is also useful if you want to force Assimp to recompute
       * normals or tangents. The corresponding steps don't recompute them if
       * they're already there (loaded from the source asset). By using this
       * step you can make sure they are NOT there.
       *
       * This flag is a poor one, mainly because its purpose is usually
       * misunderstood. Consider the following case: a 3D model has been exported
       * from a CAD app, and it has per-face vertex colors. Vertex positions can't be
       * shared, thus the #aiProcess_JoinIdenticalVertices step fails to
       * optimize the data because of these nasty little vertex colors.
       * Most apps don't even process them, so it's all for nothing. By using
       * this step, unneeded components are excluded as early as possible
       * thus opening more room for internal optimizations.
       */
      aiProcess_RemoveComponent = 0x10,
  
      // -------------------------------------------------------------------------
      /** <hr>Generates normals for all faces of all meshes.
       *
       * This is ignored if normals are already there at the time this flag
       * is evaluated. Model importers try to load them from the source file, so
       * they're usually already there. Face normals are shared between all points
       * of a single face, so a single point can have multiple normals, which
       * forces the library to duplicate vertices in some cases.
       * #aiProcess_JoinIdenticalVertices is *senseless* then.
       *
       * This flag may not be specified together with #aiProcess_GenSmoothNormals.
       */
      aiProcess_GenNormals = 0x20,
  
      // -------------------------------------------------------------------------
      /** <hr>Generates smooth normals for all vertices in the mesh.
      *
      * This is ignored if normals are already there at the time this flag
      * is evaluated. Model importers try to load them from the source file, so
      * they're usually already there.
      *
      * This flag may not be specified together with
      * #aiProcess_GenNormals. There's a importer property,
      * <tt>#AI_CONFIG_PP_GSN_MAX_SMOOTHING_ANGLE</tt> which allows you to specify
      * an angle maximum for the normal smoothing algorithm. Normals exceeding
      * this limit are not smoothed, resulting in a 'hard' seam between two faces.
      * Using a decent angle here (e.g. 80 degrees) results in very good visual
      * appearance.
      */
      aiProcess_GenSmoothNormals = 0x40,
  
      // -------------------------------------------------------------------------
      /** <hr>Splits large meshes into smaller sub-meshes.
      *
      * This is quite useful for real-time rendering, where the number of triangles
      * which can be maximally processed in a single draw-call is limited
      * by the video driver/hardware. The maximum vertex buffer is usually limited
      * too. Both requirements can be met with this step: you may specify both a
      * triangle and vertex limit for a single mesh.
      *
      * The split limits can (and should!) be set through the
      * <tt>#AI_CONFIG_PP_SLM_VERTEX_LIMIT</tt> and <tt>#AI_CONFIG_PP_SLM_TRIANGLE_LIMIT</tt>
      * importer properties. The default values are <tt>#AI_SLM_DEFAULT_MAX_VERTICES</tt> and
      * <tt>#AI_SLM_DEFAULT_MAX_TRIANGLES</tt>.
      *
      * Note that splitting is generally a time-consuming task, but only if there's
      * something to split. The use of this step is recommended for most users.
      */
      aiProcess_SplitLargeMeshes = 0x80,
  
      // -------------------------------------------------------------------------
      /** <hr>Removes the node graph and pre-transforms all vertices with
      * the local transformation matrices of their nodes.
      *
      * If the resulting scene can be reduced to a single mesh, with a single
      * material, no lights, and no cameras, then the output scene will contain
      * only a root node (with no children) that references the single mesh.
      * Otherwise, the output scene will be reduced to a root node with a single
      * level of child nodes, each one referencing one mesh, and each mesh
      * referencing one material.
      *
      * In either case, for rendering, you can
      * simply render all meshes in order - you don't need to pay
      * attention to local transformations and the node hierarchy.
      * Animations are removed during this step.
      * This step is intended for applications without a scenegraph.
      * The step CAN cause some problems: if e.g. a mesh of the asset
      * contains normals and another, using the same material index, does not,
      * they will be brought together, but the first meshes's part of
      * the normal list is zeroed. However, these artifacts are rare.
      * @note The <tt>#AI_CONFIG_PP_PTV_NORMALIZE</tt> configuration property
      * can be set to normalize the scene's spatial dimension to the -1...1
      * range.
      */
      aiProcess_PreTransformVertices = 0x100,
  
      // -------------------------------------------------------------------------
      /** <hr>Limits the number of bones simultaneously affecting a single vertex
      *  to a maximum value.
      *
      * If any vertex is affected by more than the maximum number of bones, the least
      * important vertex weights are removed and the remaining vertex weights are
      * renormalized so that the weights still sum up to 1.
      * The default bone weight limit is 4 (defined as <tt>#AI_LMW_MAX_WEIGHTS</tt> in
      * config.h), but you can use the <tt>#AI_CONFIG_PP_LBW_MAX_WEIGHTS</tt> importer
      * property to supply your own limit to the post processing step.
      *
      * If you intend to perform the skinning in hardware, this post processing
      * step might be of interest to you.
      */
      aiProcess_LimitBoneWeights = 0x200,
  
      // -------------------------------------------------------------------------
      /** <hr>Validates the imported scene data structure.
       * This makes sure that all indices are valid, all animations and
       * bones are linked correctly, all material references are correct .. etc.
       *
       * It is recommended that you capture Assimp's log output if you use this flag,
       * so you can easily find out what's wrong if a file fails the
       * validation. The validator is quite strict and will find *all*
       * inconsistencies in the data structure... It is recommended that plugin
       * developers use it to debug their loaders. There are two types of
       * validation failures:
       * <ul>
       * <li>Error: There's something wrong with the imported data. Further
       *   postprocessing is not possible and the data is not usable at all.
       *   The import fails. #Importer::GetErrorString() or #aiGetErrorString()
       *   carry the error message around.</li>
       * <li>Warning: There are some minor issues (e.g. 1000000 animation
       *   keyframes with the same time), but further postprocessing and use
       *   of the data structure is still safe. Warning details are written
       *   to the log file, <tt>#AI_SCENE_FLAGS_VALIDATION_WARNING</tt> is set
       *   in #aiScene::mFlags</li>
       * </ul>
       *
       * This post-processing step is not time-consuming. Its use is not
       * compulsory, but recommended.
      */
      aiProcess_ValidateDataStructure = 0x400,
  
      // -------------------------------------------------------------------------
      /** <hr>Reorders triangles for better vertex cache locality.
       *
       * The step tries to improve the ACMR (average post-transform vertex cache
       * miss ratio) for all meshes. The implementation runs in O(n) and is
       * roughly based on the 'tipsify' algorithm (see <a href="
       * http://www.cs.princeton.edu/gfx/pubs/Sander_2007_%3ETR/tipsy.pdf">this
       * paper</a>).
       *
       * If you intend to render huge models in hardware, this step might
       * be of interest to you. The <tt>#AI_CONFIG_PP_ICL_PTCACHE_SIZE</tt>
       * importer property can be used to fine-tune the cache optimization.
       */
      aiProcess_ImproveCacheLocality = 0x800,
  
      // -------------------------------------------------------------------------
      /** <hr>Searches for redundant/unreferenced materials and removes them.
       *
       * This is especially useful in combination with the
       * #aiProcess_PreTransformVertices and #aiProcess_OptimizeMeshes flags.
       * Both join small meshes with equal characteristics, but they can't do
       * their work if two meshes have different materials. Because several
       * material settings are lost during Assimp's import filters,
       * (and because many exporters don't check for redundant materials), huge
       * models often have materials which are are defined several times with
       * exactly the same settings.
       *
       * Several material settings not contributing to the final appearance of
       * a surface are ignored in all comparisons (e.g. the material name).
       * So, if you're passing additional information through the
       * content pipeline (probably using *magic* material names), don't
       * specify this flag. Alternatively take a look at the
       * <tt>#AI_CONFIG_PP_RRM_EXCLUDE_LIST</tt> importer property.
       */
      aiProcess_RemoveRedundantMaterials = 0x1000,
  
      // -------------------------------------------------------------------------
      /** <hr>This step tries to determine which meshes have normal vectors
       * that are facing inwards and inverts them.
       *
       * The algorithm is simple but effective:
       * the bounding box of all vertices + their normals is compared against
       * the volume of the bounding box of all vertices without their normals.
       * This works well for most objects, problems might occur with planar
       * surfaces. However, the step tries to filter such cases.
       * The step inverts all in-facing normals. Generally it is recommended
       * to enable this step, although the result is not always correct.
      */
      aiProcess_FixInfacingNormals = 0x2000,
  
  
  
      // -------------------------------------------------------------------------
      /**
       * This step generically populates aiBone->mArmature and aiBone->mNode generically
       * The point of these is it saves you later having to calculate these elements
       * This is useful when handling rest information or skin information
       * If you have multiple armatures on your models we strongly recommend enabling this
       * Instead of writing your own multi-root, multi-armature lookups we have done the
       * hard work for you :)
     */
      aiProcess_PopulateArmatureData = 0x4000,
  
      // -------------------------------------------------------------------------
      /** <hr>This step splits meshes with more than one primitive type in
       *  homogeneous sub-meshes.
       *
       *  The step is executed after the triangulation step. After the step
       *  returns, just one bit is set in aiMesh::mPrimitiveTypes. This is
       *  especially useful for real-time rendering where point and line
       *  primitives are often ignored or rendered separately.
       *  You can use the <tt>#AI_CONFIG_PP_SBP_REMOVE</tt> importer property to
       *  specify which primitive types you need. This can be used to easily
       *  exclude lines and points, which are rarely used, from the import.
      */
      aiProcess_SortByPType = 0x8000,
  
      // -------------------------------------------------------------------------
      /** <hr>This step searches all meshes for degenerate primitives and
       *  converts them to proper lines or points.
       *
       * A face is 'degenerate' if one or more of its points are identical.
       * To have the degenerate stuff not only detected and collapsed but
       * removed, try one of the following procedures:
       * <br><b>1.</b> (if you support lines and points for rendering but don't
       *    want the degenerates)<br>
       * <ul>
       *   <li>Specify the #aiProcess_FindDegenerates flag.
       *   </li>
       *   <li>Set the <tt>#AI_CONFIG_PP_FD_REMOVE</tt> importer property to
       *       1. This will cause the step to remove degenerate triangles from the
       *       import as soon as they're detected. They won't pass any further
       *       pipeline steps.
       *   </li>
       * </ul>
       * <br><b>2.</b>(if you don't support lines and points at all)<br>
       * <ul>
       *   <li>Specify the #aiProcess_FindDegenerates flag.
       *   </li>
       *   <li>Specify the #aiProcess_SortByPType flag. This moves line and
       *     point primitives to separate meshes.
       *   </li>
       *   <li>Set the <tt>#AI_CONFIG_PP_SBP_REMOVE</tt> importer property to
       *       @code aiPrimitiveType_POINTS | aiPrimitiveType_LINES
       *       @endcode to cause SortByPType to reject point
       *       and line meshes from the scene.
       *   </li>
       * </ul>
       *
       * This step also removes very small triangles with a surface area smaller
       * than 10^-6. If you rely on having these small triangles, or notice holes
       * in your model, set the property <tt>#AI_CONFIG_PP_FD_CHECKAREA</tt> to
       * false.
       * @note Degenerate polygons are not necessarily evil and that's why
       * they're not removed by default. There are several file formats which
       * don't support lines or points, and some exporters bypass the
       * format specification and write them as degenerate triangles instead.
      */
      aiProcess_FindDegenerates = 0x10000,
  
      // -------------------------------------------------------------------------
      /** <hr>This step searches all meshes for invalid data, such as zeroed
       *  normal vectors or invalid UV coords and removes/fixes them. This is
       *  intended to get rid of some common exporter errors.
       *
       * This is especially useful for normals. If they are invalid, and
       * the step recognizes this, they will be removed and can later
       * be recomputed, i.e. by the #aiProcess_GenSmoothNormals flag.<br>
       * The step will also remove meshes that are infinitely small and reduce
       * animation tracks consisting of hundreds if redundant keys to a single
       * key. The <tt>AI_CONFIG_PP_FID_ANIM_ACCURACY</tt> config property decides
       * the accuracy of the check for duplicate animation tracks.
      */
      aiProcess_FindInvalidData = 0x20000,
  
      // -------------------------------------------------------------------------
      /** <hr>This step converts non-UV mappings (such as spherical or
       *  cylindrical mapping) to proper texture coordinate channels.
       *
       * Most applications will support UV mapping only, so you will
       * probably want to specify this step in every case. Note that Assimp is not
       * always able to match the original mapping implementation of the
       * 3D app which produced a model perfectly. It's always better to let the
       * modelling app compute the UV channels - 3ds max, Maya, Blender,
       * LightWave, and Modo do this for example.
       *
       * @note If this step is not requested, you'll need to process the
       * <tt>#AI_MATKEY_MAPPING</tt> material property in order to display all assets
       * properly.
       */
      aiProcess_GenUVCoords = 0x40000,
  
      // -------------------------------------------------------------------------
      /** <hr>This step applies per-texture UV transformations and bakes
       *  them into stand-alone vtexture coordinate channels.
       *
       * UV transformations are specified per-texture - see the
       * <tt>#AI_MATKEY_UVTRANSFORM</tt> material key for more information.
       * This step processes all textures with
       * transformed input UV coordinates and generates a new (pre-transformed) UV channel
       * which replaces the old channel. Most applications won't support UV
       * transformations, so you will probably want to specify this step.
       *
       * @note UV transformations are usually implemented in real-time apps by
       * transforming texture coordinates at vertex shader stage with a 3x3
       * (homogeneous) transformation matrix.
      */
      aiProcess_TransformUVCoords = 0x80000,
  
      // -------------------------------------------------------------------------
      /** <hr>This step searches for duplicate meshes and replaces them
       *  with references to the first mesh.
       *
       *  This step takes a while, so don't use it if speed is a concern.
       *  Its main purpose is to workaround the fact that many export
       *  file formats don't support instanced meshes, so exporters need to
       *  duplicate meshes. This step removes the duplicates again. Please
       *  note that Assimp does not currently support per-node material
       *  assignment to meshes, which means that identical meshes with
       *  different materials are currently *not* joined, although this is
       *  planned for future versions.
       */
      aiProcess_FindInstances = 0x100000,
  
      // -------------------------------------------------------------------------
      /** <hr>A post-processing step to reduce the number of meshes.
       *
       *  This will, in fact, reduce the number of draw calls.
       *
       *  This is a very effective optimization and is recommended to be used
       *  together with #aiProcess_OptimizeGraph, if possible. The flag is fully
       *  compatible with both #aiProcess_SplitLargeMeshes and #aiProcess_SortByPType.
      */
      aiProcess_OptimizeMeshes  = 0x200000,
  
  
      // -------------------------------------------------------------------------
      /** <hr>A post-processing step to optimize the scene hierarchy.
       *
       *  Nodes without animations, bones, lights or cameras assigned are
       *  collapsed and joined.
       *
       *  Node names can be lost during this step. If you use special 'tag nodes'
       *  to pass additional information through your content pipeline, use the
       *  <tt>#AI_CONFIG_PP_OG_EXCLUDE_LIST</tt> importer property to specify a
       *  list of node names you want to be kept. Nodes matching one of the names
       *  in this list won't be touched or modified.
       *
       *  Use this flag with caution. Most simple files will be collapsed to a
       *  single node, so complex hierarchies are usually completely lost. This is not
       *  useful for editor environments, but probably a very effective
       *  optimization if you just want to get the model data, convert it to your
       *  own format, and render it as fast as possible.
       *
       *  This flag is designed to be used with #aiProcess_OptimizeMeshes for best
       *  results.
       *
       *  @note 'Crappy' scenes with thousands of extremely small meshes packed
       *  in deeply nested nodes exist for almost all file formats.
       *  #aiProcess_OptimizeMeshes in combination with #aiProcess_OptimizeGraph
       *  usually fixes them all and makes them renderable.
      */
      aiProcess_OptimizeGraph  = 0x400000,
  
      // -------------------------------------------------------------------------
      /** <hr>This step flips all UV coordinates along the y-axis and adjusts
       * material settings and bitangents accordingly.
       *
       * <b>Output UV coordinate system:</b>
       * @code
       * 0y|0y ---------- 1x|0y
       * |                 |
       * |                 |
       * |                 |
       * 0x|1y ---------- 1x|1y
       * @endcode
       *
       * You'll probably want to consider this flag if you use Direct3D for
       * rendering. The #aiProcess_ConvertToLeftHanded flag supersedes this
       * setting and bundles all conversions typically required for D3D-based
       * applications.
      */
      aiProcess_FlipUVs = 0x800000,
  
      // -------------------------------------------------------------------------
      /** <hr>This step adjusts the output face winding order to be CW.
       *
       * The default face winding order is counter clockwise (CCW).
       *
       * <b>Output face order:</b>
       * @code
       *       x2
       *
       *                         x0
       *  x1
       * @endcode
      */
      aiProcess_FlipWindingOrder  = 0x1000000,
  
      // -------------------------------------------------------------------------
      /** <hr>This step splits meshes with many bones into sub-meshes so that each
       * sub-mesh has fewer or as many bones as a given limit.
      */
      aiProcess_SplitByBoneCount  = 0x2000000,
  
      // -------------------------------------------------------------------------
      /** <hr>This step removes bones losslessly or according to some threshold.
       *
       *  In some cases (i.e. formats that require it) exporters are forced to
       *  assign dummy bone weights to otherwise static meshes assigned to
       *  animated meshes. Full, weight-based skinning is expensive while
       *  animating nodes is extremely cheap, so this step is offered to clean up
       *  the data in that regard.
       *
       *  Use <tt>#AI_CONFIG_PP_DB_THRESHOLD</tt> to control this.
       *  Use <tt>#AI_CONFIG_PP_DB_ALL_OR_NONE</tt> if you want bones removed if and
       *  only if all bones within the scene qualify for removal.
      */
      aiProcess_Debone  = 0x4000000,
  
  
  
      // -------------------------------------------------------------------------
      /** <hr>This step will perform a global scale of the model.
      *
      *  Some importers are providing a mechanism to define a scaling unit for the
      *  model. This post processing step can be used to do so. You need to get the
      *  global scaling from your importer settings like in FBX. Use the flag
      *  AI_CONFIG_GLOBAL_SCALE_FACTOR_KEY from the global property table to configure this.
      *
      *  Use <tt>#AI_CONFIG_GLOBAL_SCALE_FACTOR_KEY</tt> to setup the global scaling factor.
      */
      aiProcess_GlobalScale = 0x8000000,
  
      // -------------------------------------------------------------------------
      /** <hr>A postprocessing step to embed of textures.
       *
       *  This will remove external data dependencies for textures.
       *  If a texture's file does not exist at the specified path
       *  (due, for instance, to an absolute path generated on another system),
       *  it will check if a file with the same name exists at the root folder
       *  of the imported model. And if so, it uses that.
       */
      aiProcess_EmbedTextures  = 0x10000000,
  
      // aiProcess_GenEntityMeshes = 0x100000,
      // aiProcess_OptimizeAnimations = 0x200000
      // aiProcess_FixTexturePaths = 0x200000
  
  
      aiProcess_ForceGenNormals = 0x20000000,
  
      // -------------------------------------------------------------------------
      /** <hr>Drops normals for all faces of all meshes.
       *
       * This is ignored if no normals are present.
       * Face normals are shared between all points of a single face,
       * so a single point can have multiple normals, which
       * forces the library to duplicate vertices in some cases.
       * #aiProcess_JoinIdenticalVertices is *senseless* then.
       * This process gives sense back to aiProcess_JoinIdenticalVertices
       */
      aiProcess_DropNormals = 0x40000000,
  
      // -------------------------------------------------------------------------
      /**
       */
      aiProcess_GenBoundingBoxes = 0x80000000
  };
  
  
  // ---------------------------------------------------------------------------------------
  /** @def aiProcess_ConvertToLeftHanded
   *  @brief Shortcut flag for Direct3D-based applications.
   *
   *  Supersedes the #aiProcess_MakeLeftHanded and #aiProcess_FlipUVs and
   *  #aiProcess_FlipWindingOrder flags.
   *  The output data matches Direct3D's conventions: left-handed geometry, upper-left
   *  origin for UV coordinates and finally clockwise face order, suitable for CCW culling.
   *
   *  @deprecated
   */
  #define aiProcess_ConvertToLeftHanded ( \
      aiProcess_MakeLeftHanded     | \
      aiProcess_FlipUVs            | \
      aiProcess_FlipWindingOrder   | \
      0 )
  
  
  // ---------------------------------------------------------------------------------------
  /** @def aiProcessPreset_TargetRealtime_Fast
   *  @brief Default postprocess configuration optimizing the data for real-time rendering.
   *
   *  Applications would want to use this preset to load models on end-user PCs,
   *  maybe for direct use in game.
   *
   * If you're using DirectX, don't forget to combine this value with
   * the #aiProcess_ConvertToLeftHanded step. If you don't support UV transformations
   * in your application apply the #aiProcess_TransformUVCoords step, too.
   *  @note Please take the time to read the docs for the steps enabled by this preset.
   *  Some of them offer further configurable properties, while some of them might not be of
   *  use for you so it might be better to not specify them.
   */
  #define aiProcessPreset_TargetRealtime_Fast ( \
      aiProcess_CalcTangentSpace      |  \
      aiProcess_GenNormals            |  \
      aiProcess_JoinIdenticalVertices |  \
      aiProcess_Triangulate           |  \
      aiProcess_GenUVCoords           |  \
      aiProcess_SortByPType           |  \
      0 )
  
   // ---------------------------------------------------------------------------------------
   /** @def aiProcessPreset_TargetRealtime_Quality
    *  @brief Default postprocess configuration optimizing the data for real-time rendering.
    *
    *  Unlike #aiProcessPreset_TargetRealtime_Fast, this configuration
    *  performs some extra optimizations to improve rendering speed and
    *  to minimize memory usage. It could be a good choice for a level editor
    *  environment where import speed is not so important.
    *
    *  If you're using DirectX, don't forget to combine this value with
    *  the #aiProcess_ConvertToLeftHanded step. If you don't support UV transformations
    *  in your application apply the #aiProcess_TransformUVCoords step, too.
    *  @note Please take the time to read the docs for the steps enabled by this preset.
    *  Some of them offer further configurable properties, while some of them might not be
    *  of use for you so it might be better to not specify them.
    */
  #define aiProcessPreset_TargetRealtime_Quality ( \
      aiProcess_CalcTangentSpace              |  \
      aiProcess_GenSmoothNormals              |  \
      aiProcess_JoinIdenticalVertices         |  \
      aiProcess_ImproveCacheLocality          |  \
      aiProcess_LimitBoneWeights              |  \
      aiProcess_RemoveRedundantMaterials      |  \
      aiProcess_SplitLargeMeshes              |  \
      aiProcess_Triangulate                   |  \
      aiProcess_GenUVCoords                   |  \
      aiProcess_SortByPType                   |  \
      aiProcess_FindDegenerates               |  \
      aiProcess_FindInvalidData               |  \
      0 )
  
   // ---------------------------------------------------------------------------------------
   /** @def aiProcessPreset_TargetRealtime_MaxQuality
    *  @brief Default postprocess configuration optimizing the data for real-time rendering.
    *
    *  This preset enables almost every optimization step to achieve perfectly
    *  optimized data. It's your choice for level editor environments where import speed
    *  is not important.
    *
    *  If you're using DirectX, don't forget to combine this value with
    *  the #aiProcess_ConvertToLeftHanded step. If you don't support UV transformations
    *  in your application, apply the #aiProcess_TransformUVCoords step, too.
    *  @note Please take the time to read the docs for the steps enabled by this preset.
    *  Some of them offer further configurable properties, while some of them might not be
    *  of use for you so it might be better to not specify them.
    */
  #define aiProcessPreset_TargetRealtime_MaxQuality ( \
      aiProcessPreset_TargetRealtime_Quality   |  \
      aiProcess_FindInstances                  |  \
      aiProcess_ValidateDataStructure          |  \
      aiProcess_OptimizeMeshes                 |  \
      0 )
  
  
  #ifdef __cplusplus
  } // end of extern "C"
  #endif
  
  #endif // AI_POSTPROCESS_H_INC
  