assimp/code/PostProcessing/SplitLargeMeshes.h

/*
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*/

/** @file Defines a post processing step to split large meshes into sub-meshes
 */
#ifndef AI_SPLITLARGEMESHES_H_INC
#define AI_SPLITLARGEMESHES_H_INC

#include <vector>
#include "Common/BaseProcess.h"

#include <assimp/mesh.h>
#include <assimp/scene.h>

// Forward declarations
class SplitLargeMeshesTest;

namespace Assimp {

class SplitLargeMeshesProcess_Triangle;
class SplitLargeMeshesProcess_Vertex;

// NOTE: If you change these limits, don't forget to change the
// corresponding values in all Assimp ports

// **********************************************************
// Java: ConfigProperty.java,
//  ConfigProperty.DEFAULT_VERTEX_SPLIT_LIMIT
//  ConfigProperty.DEFAULT_TRIANGLE_SPLIT_LIMIT
// **********************************************************

// default limit for vertices
#if (!defined AI_SLM_DEFAULT_MAX_VERTICES)
#   define AI_SLM_DEFAULT_MAX_VERTICES      1000000
#endif

// default limit for triangles
#if (!defined AI_SLM_DEFAULT_MAX_TRIANGLES)
#   define AI_SLM_DEFAULT_MAX_TRIANGLES     1000000
#endif

// ---------------------------------------------------------------------------
/** Post-processing filter to split large meshes into sub-meshes
 *
 * Applied BEFORE the JoinVertices-Step occurs.
 * Returns NON-UNIQUE vertices, splits by triangle number.
*/
class ASSIMP_API SplitLargeMeshesProcess_Triangle : public BaseProcess {
    friend class SplitLargeMeshesProcess_Vertex;

public:
    // -------------------------------------------------------------------
    /// The default class constructor / destructor.
    SplitLargeMeshesProcess_Triangle();
    ~SplitLargeMeshesProcess_Triangle() override = default;

    // -------------------------------------------------------------------
    /** Returns whether the processing step is present in the given flag.
    * @param pFlags The processing flags the importer was called with. A
    *   bitwise combination of #aiPostProcessSteps.
    * @return true if the process is present in this flag fields,
    *   false if not.
    */
    bool IsActive( unsigned int pFlags) const override;

    // -------------------------------------------------------------------
    /** Called prior to ExecuteOnScene().
    * The function is a request to the process to update its configuration
    * basing on the Importer's configuration property list.
    */
    void SetupProperties(const Importer* pImp) override;

    //! Set the split limit - needed for unit testing
    inline void SetLimit(unsigned int l)
        {LIMIT = l;}

    //! Get the split limit
    inline unsigned int GetLimit() const
        {return LIMIT;}

    // -------------------------------------------------------------------
    /** Executes the post processing step on the given imported data.
    * At the moment a process is not supposed to fail.
    * @param pScene The imported data to work at.
    */
    void Execute( aiScene* pScene) override;

    // -------------------------------------------------------------------
    //! Apply the algorithm to a given mesh
    void SplitMesh (unsigned int a, aiMesh* pcMesh,
        std::vector<std::pair<aiMesh*, unsigned int> >& avList);

    // -------------------------------------------------------------------
    //! Update a node in the asset after a few of its meshes
    //! have been split
    static void UpdateNode(aiNode* pcNode,
        const std::vector<std::pair<aiMesh*, unsigned int> >& avList);

public:
    //! Triangle limit
    unsigned int LIMIT;
};

// ---------------------------------------------------------------------------
/** Post-processing filter to split large meshes into sub-meshes
 *
 * Applied AFTER the JoinVertices-Step occurs.
 * Returns UNIQUE vertices, splits by vertex number.
*/
class ASSIMP_API SplitLargeMeshesProcess_Vertex : public BaseProcess {
public:
    SplitLargeMeshesProcess_Vertex();
    ~SplitLargeMeshesProcess_Vertex() override = default;

    // -------------------------------------------------------------------
    /** Returns whether the processing step is present in the given flag field.
    * @param pFlags The processing flags the importer was called with. A bitwise
    *   combination of #aiPostProcessSteps.
    * @return true if the process is present in this flag fields, false if not.
    */
    bool IsActive( unsigned int pFlags) const override;

    // -------------------------------------------------------------------
    /** Called prior to ExecuteOnScene().
    * The function is a request to the process to update its configuration
    * basing on the Importer's configuration property list.
    */
    void SetupProperties(const Importer* pImp) override;

    //! Set the split limit - needed for unit testing
    inline void SetLimit(unsigned int l)
        {LIMIT = l;}

    //! Get the split limit
    inline unsigned int GetLimit() const
        {return LIMIT;}

    // -------------------------------------------------------------------
    /** Executes the post processing step on the given imported data.
    * At the moment a process is not supposed to fail.
    * @param pScene The imported data to work at.
    */
    void Execute( aiScene* pScene) override;

    // -------------------------------------------------------------------
    //! Apply the algorithm to a given mesh
    void SplitMesh (unsigned int a, aiMesh* pcMesh,
        std::vector<std::pair<aiMesh*, unsigned int> >& avList);

    // NOTE: Reuse SplitLargeMeshesProcess_Triangle::UpdateNode()

public:
    //! Triangle limit
    unsigned int LIMIT;
};

} // end of namespace Assimp

#endif // !!AI_SPLITLARGEMESHES_H_INC