assimp.assimp/include/assimp/postprocess.h

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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.
     * Unless the importer (like ply) had to split vertices. Then you need one regardless.
     */
    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_POINT | aiPrimitiveType_LINE
     *       @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