assimp.assimp/code/PostProcessing/OptimizeGraph.h

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*/

/** @file  OptimizeGraph.h
 *  @brief Declares a post processing step to optimize the scenegraph
 */
#ifndef AI_OPTIMIZEGRAPHPROCESS_H_INC
#define AI_OPTIMIZEGRAPHPROCESS_H_INC

#include "Common/BaseProcess.h"
#include "PostProcessing/ProcessHelper.h"

#include <assimp/types.h>

#include <set>

// Forward declarations
struct aiMesh;

class OptimizeGraphProcessTest;

namespace Assimp {

// -----------------------------------------------------------------------------
/** @brief Postprocessing step to optimize the scenegraph
 *
 *  The implementation tries to merge nodes, even if they use different
 *  transformations. Animations are preserved.
 *
 *  @see aiProcess_OptimizeGraph for a detailed description of the
 *  algorithm being applied.
 */
class OptimizeGraphProcess : public BaseProcess {
public:
    // -------------------------------------------------------------------
    /// The default class constructor / destructor.
    OptimizeGraphProcess();
    ~OptimizeGraphProcess() override = default;

    // -------------------------------------------------------------------
    bool IsActive( unsigned int pFlags) const override;

    // -------------------------------------------------------------------
    void Execute( aiScene* pScene) override;

    // -------------------------------------------------------------------
    void SetupProperties(const Importer* pImp) override;

    // -------------------------------------------------------------------
    /** @brief Add a list of node names to be locked and not modified.
     *  @param in List of nodes. See #AI_CONFIG_PP_OG_EXCLUDE_LIST for
     *    format explanations.
     */
    inline void AddLockedNodeList(std::string& in) {
        ConvertListToStrings (in,locked_nodes);
    }

    // -------------------------------------------------------------------
    /** @brief Add another node to be locked and not modified.
     *  @param name Name to be locked
     */
    inline void AddLockedNode(std::string& name) {
        locked_nodes.push_back(name);
    }

    // -------------------------------------------------------------------
    /** @brief Remove a node from the list of locked nodes.
     *  @param name Name to be unlocked
     */
    inline void RemoveLockedNode(std::string& name) {
        locked_nodes.remove(name);
    }

protected:
    void CollectNewChildren(aiNode* nd, std::list<aiNode*>& nodes);
    void FindInstancedMeshes (aiNode* pNode);

private:
#ifdef AI_OG_USE_HASHING
    typedef std::set<unsigned int> LockedSetType;
#else
    typedef std::set<std::string> LockedSetType;
#endif

    //! Scene we're working with
    aiScene* mScene;

    //! List of locked names. Stored is the hash of the name
    LockedSetType locked;

    //! List of nodes to be locked in addition to those with animations, lights or cameras assigned.
    std::list<std::string> locked_nodes;

    //! Node counters for logging purposes
    unsigned int nodes_in,nodes_out, count_merged;

    //! Reference counters for meshes
    std::vector<unsigned int> meshes;
};

} // end of namespace Assimp

#endif // AI_OPTIMIZEGRAPHPROCESS_H_INC