assimp/include/aiMesh.h

/*
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Open Asset Import Library (ASSIMP)
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*/

/** @file aiMesh.h
 *  @brief Declares the data structures in which the imported geometry is 
    returned by ASSIMP: aiMesh, aiFace and aiBone data structures.
 */
#ifndef INCLUDED_AI_MESH_H
#define INCLUDED_AI_MESH_H

#include "aiTypes.h"

#ifdef __cplusplus
extern "C" {
#endif

// ---------------------------------------------------------------------------
/** @brief A single face in a mesh, referring to multiple vertices. 
 *
 * If mNumIndices is 3, we call the face 'triangle', for mNumIndices > 3 
 * it's called 'polygon' (hey, that's just a definition!).
 * <br>
 * aiMesh::mPrimitiveTypes can be queried to quickly examine which types of
 * primitive are actually present in a mesh. The #aiProcess_SortByPType flag 
 * executes a special post-processing algorithm which splits meshes with
 * *different* primitive types mixed up (e.g. lines and triangles) in several
 * 'clean' submeshes. Furthermore there is a configuration option (
 * #AI_CONFIG_PP_SBP_REMOVE) to force #aiProcess_SortByPType to remove 
 * specific kinds of primitives from the imported scene, completely and forever.
 * In many cases you'll probably want to set this setting to 
 * @code 
 * aiPrimitiveType_LINE|aiPrimitiveType_POINT
 * @endcode
 * Together with the #aiProcess_Triangulate flag you can then be sure that
 * #aiFace::mNumIndices is always 3. 
 * @note Take a look at the @link data Data Structures page @endlink for
 * more information on the layout and winding order of a face.
 */
struct aiFace
{
	//! Number of indices defining this face. 3 for a triangle, >3 for polygon
	unsigned int mNumIndices; 

	//! Pointer to the indices array. Size of the array is given in numIndices.
	unsigned int* mIndices;   

#ifdef __cplusplus

	//! Default constructor
	aiFace()
	{
		mNumIndices = 0; mIndices = NULL;
	}

	//! Default destructor. Delete the index array
	~aiFace()
	{
		delete [] mIndices;
	}

	//! Copy constructor. Copy the index array
	aiFace( const aiFace& o)
	{
		mIndices = NULL;
		*this = o;
	}

	//! Assignment operator. Copy the index array
	const aiFace& operator = ( const aiFace& o)
	{
		if (&o == this)
			return *this;

		delete[] mIndices;
		mNumIndices = o.mNumIndices;
		mIndices = new unsigned int[mNumIndices];
		::memcpy( mIndices, o.mIndices, mNumIndices * sizeof( unsigned int));
		return *this;
	}

	//! Comparison operator. Checks whether the index array 
	//! of two faces is identical
	bool operator== (const aiFace& o) const
	{
		if (mIndices == o.mIndices)return true;
		else if (mIndices && mNumIndices == o.mNumIndices)
		{
			for (unsigned int i = 0;i < this->mNumIndices;++i)
				if (mIndices[i] != o.mIndices[i])return false;
			return true;
		}
		return false;
	}

	//! Inverse comparison operator. Checks whether the index 
	//! array of two faces is NOT identical
	bool operator != (const aiFace& o) const
	{
		return !(*this == o);
	}
#endif // __cplusplus
}; // struct aiFace


// ---------------------------------------------------------------------------
/** @brief A single influence of a bone on a vertex.
 */
struct aiVertexWeight
{
	//! Index of the vertex which is influenced by the bone.
	unsigned int mVertexId;

	//! The strength of the influence in the range (0...1).
	//! The influence from all bones at one vertex amounts to 1.
	float mWeight;     

#ifdef __cplusplus

	//! Default constructor
	aiVertexWeight() { }

	//! Initialisation from a given index and vertex weight factor
	//! \param pID ID
	//! \param pWeight Vertex weight factor
	aiVertexWeight( unsigned int pID, float pWeight) 
		: mVertexId( pID), mWeight( pWeight) 
	{ /* nothing to do here */ }

#endif // __cplusplus
};


// ---------------------------------------------------------------------------
/** @brief A single bone of a mesh.
 *
 *  A bone has a name by which it can be found in the frame hierarchy and by
 *  which it can be addressed by animations. In addition it has a number of 
 *  influences on vertices.
 */
struct aiBone
{
	//! The name of the bone. 
	C_STRUCT aiString mName;

	//! The number of vertices affected by this bone
	unsigned int mNumWeights;

	//! The vertices affected by this bone
	C_STRUCT aiVertexWeight* mWeights;

	//! Matrix that transforms from mesh space to bone space in bind pose
	C_STRUCT aiMatrix4x4 mOffsetMatrix;

#ifdef __cplusplus

	//! Default constructor
	aiBone()
	{
		mNumWeights = 0; mWeights = NULL;
	}

	//! Copy constructor
	aiBone(const aiBone& other)
	{
		mNumWeights = other.mNumWeights;
		mOffsetMatrix = other.mOffsetMatrix;
		mName = other.mName;

		if (other.mWeights && other.mNumWeights)
		{
			mWeights = new aiVertexWeight[mNumWeights];
			::memcpy(mWeights,other.mWeights,mNumWeights * sizeof(aiVertexWeight));
		}
	}

	//! Destructor - deletes the array of vertex weights
	~aiBone()
	{
		delete [] mWeights;
	}
#endif // __cplusplus
};

#ifndef AI_MAX_NUMBER_OF_COLOR_SETS
// ---------------------------------------------------------------------------
/** @def AI_MAX_NUMBER_OF_COLOR_SETS
 *  Maximum number of vertex color sets per mesh.
 *
 *  Normally: Diffuse, specular, ambient and emissive
 *  However one could use the vertex color sets for any other purpose, too.
 *
 *  @note Some internal structures expect (and assert) this value
 *    to be at least 4. For the moment it is absolutely safe to assume that
 *    this will never change.
 */
#	define AI_MAX_NUMBER_OF_COLOR_SETS 0x4
#endif // !! AI_MAX_NUMBER_OF_COLOR_SETS

#ifndef AI_MAX_NUMBER_OF_TEXTURECOORDS
// ---------------------------------------------------------------------------
/** @def AI_MAX_NUMBER_OF_TEXTURECOORDS
 *  Maximum number of texture coord sets (UV(W) channels) per mesh 
 *
 *  The material system uses the AI_MATKEY_UVWSRC_XXX keys to specify 
 *  which UVW channel serves as data source for a texture.
 *
 *  @note Some internal structures expect (and assert) this value
 *    to be at least 4. For the moment it is absolutely safe to assume that
 *    this will never change.
*/
#	define AI_MAX_NUMBER_OF_TEXTURECOORDS 0x4
#endif // !! AI_MAX_NUMBER_OF_TEXTURECOORDS


// ---------------------------------------------------------------------------
/** @brief Enumerates the types of geometric primitives supported by Assimp.
 *  
 *  @see aiFace Face data structure
 *  @see aiProcess_SortByPType Per-primitive sorting of meshes
 *  @see aiProcess_Triangulate Automatic triangulation
 *  @see AI_CONFIG_PP_SBP_REMOVE Removal of specific primitive types.
 */
enum aiPrimitiveType
{
	/** A point primitive. 
	 *
	 * This is just a single vertex in the virtual world, 
	 * #aiFace contains just one index for such a primitive.
	 */
	aiPrimitiveType_POINT       = 0x1,

	/** A line primitive. 
	 *
	 * This is a line defined through a start and an end position.
	 * #aiFace contains exactly two indices for such a primitive.
	 */
	aiPrimitiveType_LINE        = 0x2,

	/** A triangular primitive. 
	 *
	 * A triangle consists of three indices.
	 */
	aiPrimitiveType_TRIANGLE    = 0x4,

	/** A higher-level polygon with more than 3 edges.
	 *
	 * A triangle is a polygon, but polygon in this context means
	 * "all polygons that are not triangles". The "Triangulate"-Step
	 * is provided for your convenience, it splits all polygons in
	 * triangles (which are much easier to handle).
	 */
	aiPrimitiveType_POLYGON     = 0x8,


	/** This value is not used. It is just here to force the
	 *  compiler to map this enum to a 32 Bit integer.
	 */
#ifndef SWIG
	_aiPrimitiveType_Force32Bit = 0x9fffffff
#endif
}; //! enum aiPrimitiveType

// Get the #aiPrimitiveType flag for a specific number of face indices
#define AI_PRIMITIVE_TYPE_FOR_N_INDICES(n) \
	((n) > 3 ? aiPrimitiveType_POLYGON : (aiPrimitiveType)(1u << ((n)-1)))

// ---------------------------------------------------------------------------
/** @brief A mesh represents a geometry or model with a single material. 
*
* It usually consists of a number of vertices and a series of primitives/faces 
* referencing the vertices. In addition there might be a series of bones, each 
* of them addressing a number of vertices with a certain weight. Vertex data 
* is presented in channels with each channel containing a single per-vertex 
* information such as a set of texture coords or a normal vector.
* If a data pointer is non-null, the corresponding data stream is present.
* From C++-programs you can also use the comfort functions Has*() to
* test for the presence of various data streams.
*
* A Mesh uses only a single material which is referenced by a material ID.
* @note The mPositions member is usually not optional. However, vertex positions 
* *could* be missing if the AI_SCENE_FLAGS_INCOMPLETE flag is set in 
* @code
* aiScene::mFlags
* @endcode
*/
struct aiMesh
{
	/** Bitwise combination of the members of the #aiPrimitiveType enum.
	 * This specifies which types of primitives are present in the mesh.
	 * The "SortByPrimitiveType"-Step can be used to make sure the 
	 * output meshes consist of one primitive type each.
	 */
	unsigned int mPrimitiveTypes;

	/** The number of vertices in this mesh. 
	* This is also the size of all of the per-vertex data arrays
	*/
	unsigned int mNumVertices;

	/** The number of primitives (triangles, polygons, lines) in this  mesh. 
	* This is also the size of the mFaces array 
	*/
	unsigned int mNumFaces;

	/** Vertex positions. 
	* This array is always present in a mesh. The array is 
	* mNumVertices in size. 
	*/
	C_STRUCT aiVector3D* mVertices;

	/** Vertex normals. 
	* The array contains normalized vectors, NULL if not present. 
	* The array is mNumVertices in size. Normals are undefined for
	* point and line primitives. A mesh consisting of points and
	* lines only may not have normal vectors. Meshes with mixed
	* primitive types (i.e. lines and triangles) may have normals,
	* but the normals for vertices that are only referenced by
	* point or line primitives are undefined and set to QNaN (WARN:
	* qNaN compares to inequal to *everything*, even to qNaN itself.
	* Use code like this
	* @code
	* #define IS_QNAN(f) (f != f)
	* @endcode
	* to check whether a field is qnan).
	* @note Normal vectors computed by Assimp are always unit-length.
	* However, this needn't apply for normals that have been taken
	*   directly from the model file.
	*/
	C_STRUCT aiVector3D* mNormals;

	/** Vertex tangents. 
	* The tangent of a vertex points in the direction of the positive 
	* X texture axis. The array contains normalized vectors, NULL if
	* not present. The array is mNumVertices in size. A mesh consisting 
	* of points and lines only may not have normal vectors. Meshes with 
	* mixed primitive types (i.e. lines and triangles) may have 
	* normals, but the normals for vertices that are only referenced by
	* point or line primitives are undefined and set to QNaN. 
	* @note If the mesh contains tangents, it automatically also 
	* contains bitangents (the bitangent is just the cross product of
	* tangent and normal vectors). 
	*/
	C_STRUCT aiVector3D* mTangents;

	/** Vertex bitangents. 
	* The bitangent of a vertex points in the direction of the positive 
	* Y texture axis. The array contains normalized vectors, NULL if not
	* present. The array is mNumVertices in size. 
	* @note If the mesh contains tangents, it automatically also contains
	* bitangents. 
	*/
	C_STRUCT aiVector3D* mBitangents;

	/** Vertex color sets. 
	* A mesh may contain 0 to #AI_MAX_NUMBER_OF_COLOR_SETS vertex 
	* colors per vertex. NULL if not present. Each array is
	* mNumVertices in size if present.
	*/
	C_STRUCT aiColor4D* mColors[AI_MAX_NUMBER_OF_COLOR_SETS];

	/** Vertex texture coords, also known as UV channels.
	* A mesh may contain 0 to AI_MAX_NUMBER_OF_TEXTURECOORDS per
	* vertex. NULL if not present. The array is mNumVertices in size. 
	*/
	C_STRUCT aiVector3D* mTextureCoords[AI_MAX_NUMBER_OF_TEXTURECOORDS];

	/** Specifies the number of components for a given UV channel.
	* Up to three channels are supported (UVW, for accessing volume
	* or cube maps). If the value is 2 for a given channel n, the
	* component p.z of mTextureCoords[n][p] is set to 0.0f.
	* If the value is 1 for a given channel, p.y is set to 0.0f, too.
	* @note 4D coords are not supported 
	*/
	unsigned int mNumUVComponents[AI_MAX_NUMBER_OF_TEXTURECOORDS];

	/** The faces the mesh is constructed from. 
	* Each face refers to a number of vertices by their indices. 
	* This array is always present in a mesh, its size is given 
	* in mNumFaces. If the AI_SCENE_FLAGS_NON_VERBOSE_FORMAT
	* is NOT set each face references an unique set of vertices.
	*/
	C_STRUCT aiFace* mFaces;

	/** The number of bones this mesh contains. 
	* Can be 0, in which case the mBones array is NULL. 
	*/
	unsigned int mNumBones;

	/** The bones of this mesh. 
	* A bone consists of a name by which it can be found in the
	* frame hierarchy and a set of vertex weights.
	*/
	C_STRUCT aiBone** mBones;

	/** The material used by this mesh. 
	 * A mesh does use only a single material. If an imported model uses
	 * multiple materials, the import splits up the mesh. Use this value 
	 * as index into the scene's material list.
	 */
	unsigned int mMaterialIndex;

#ifdef __cplusplus

	//! Default constructor. Initializes all members to 0
	aiMesh()
	{
		mNumVertices    = 0; 
		mNumFaces       = 0;
		mPrimitiveTypes = 0;
		mVertices = NULL; mFaces    = NULL;
		mNormals  = NULL; mTangents = NULL;
		mBitangents = NULL;
		for( unsigned int a = 0; a < AI_MAX_NUMBER_OF_TEXTURECOORDS; a++)
		{
			mNumUVComponents[a] = 0;
			mTextureCoords[a] = NULL;
		}
		for( unsigned int a = 0; a < AI_MAX_NUMBER_OF_COLOR_SETS; a++)
			mColors[a] = NULL;
		mNumBones = 0; mBones = NULL;
		mMaterialIndex = 0;
	}

	//! Deletes all storage allocated for the mesh
	~aiMesh()
	{
		delete [] mVertices; 
		delete [] mNormals;
		delete [] mTangents;
		delete [] mBitangents;
		for( unsigned int a = 0; a < AI_MAX_NUMBER_OF_TEXTURECOORDS; a++)
			delete [] mTextureCoords[a];
		for( unsigned int a = 0; a < AI_MAX_NUMBER_OF_COLOR_SETS; a++)
			delete [] mColors[a];

		// DO NOT REMOVE THIS ADDITIONAL CHECK
		if (mNumBones && mBones)
		{
			for( unsigned int a = 0; a < mNumBones; a++)
				delete mBones[a];
			delete [] mBones;
		}
		delete [] mFaces;
	}

	//! Check whether the mesh contains positions. If no special scene flags
	//! (such as AI_SCENE_FLAGS_ANIM_SKELETON_ONLY) are set this will
	//! always return true 
	bool HasPositions() const 
		{ return mVertices != NULL && mNumVertices > 0; }

	//! Check whether the mesh contains faces. If no special scene flags
	//! are set this should always return true
	bool HasFaces() const 
		{ return mFaces != NULL && mNumFaces > 0; }

	//! Check whether the mesh contains normal vectors
	bool HasNormals() const 
		{ return mNormals != NULL && mNumVertices > 0; }

	//! Check whether the mesh contains tangent and bitangent vectors
	//! It is not possible that it contains tangents and no bitangents
	//! (or the other way round). The existence of one of them
	//! implies that the second is there, too.
	bool HasTangentsAndBitangents() const 
		{ return mTangents != NULL && mBitangents != NULL && mNumVertices > 0; }

	//! Check whether the mesh contains a vertex color set
	//! \param pIndex Index of the vertex color set
	bool HasVertexColors( unsigned int pIndex) const
	{ 
		if( pIndex >= AI_MAX_NUMBER_OF_COLOR_SETS) 
			return false; 
		else 
			return mColors[pIndex] != NULL && mNumVertices > 0; 
	}

	//! Check whether the mesh contains a texture coordinate set
	//! \param pIndex Index of the texture coordinates set
	bool HasTextureCoords( unsigned int pIndex) const
	{ 
		if( pIndex >= AI_MAX_NUMBER_OF_TEXTURECOORDS) 
			return false; 
		else 
			return mTextureCoords[pIndex] != NULL && mNumVertices > 0; 
	}

	//! Get the number of UV channels the mesh contains
	unsigned int GetNumUVChannels() const 
	{
		unsigned int n = 0;
		while (n < AI_MAX_NUMBER_OF_TEXTURECOORDS && mTextureCoords[n])++n;
		return n;
	}

	//! Get the number of vertex color channels the mesh contains
	unsigned int GetNumColorChannels() const 
	{
		unsigned int n = 0;
		while (n < AI_MAX_NUMBER_OF_COLOR_SETS && mColors[n])++n;
		return n;
	}

	//! Check whether the mesh contains bones
	inline bool HasBones() const
		{ return mBones != NULL && mNumBones > 0; }

#endif // __cplusplus
};

#ifdef __cplusplus
}
#endif //! extern "C"
#endif // __AI_MESH_H_INC