add assimp submodule

1 files changed, 708 insertions, 0 deletions

diff --git a/src/mesh/assimp-master/include/assimp/postprocess.h b/src/mesh/assimp-master/include/assimp/postprocess.h
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+/*
+Open Asset Import Library (assimp)
+----------------------------------------------------------------------
+
+Copyright (c) 2006-2022, assimp team
+
+
+All rights reserved.
+
+Redistribution and use of this software in source and binary forms,
+with or without modification, are permitted provided that the
+following conditions are met:
+
+* Redistributions of source code must retain the above
+  copyright notice, this list of conditions and the
+  following disclaimer.
+
+* Redistributions in binary form must reproduce the above
+  copyright notice, this list of conditions and the
+  following disclaimer in the documentation and/or other
+  materials provided with the distribution.
+
+* Neither the name of the assimp team, nor the names of its
+  contributors may be used to endorse or promote products
+  derived from this software without specific prior
+  written permission of the assimp team.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+----------------------------------------------------------------------
+*/
+
+/** @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