packedshareddata/GU_PackedSharedData.h

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#ifndef __GU_PackedSharedData__
#define __GU_PackedSharedData__

#include <GU/GU_PackedImpl.h>
#include <UT/UT_SharedPtr.h>

class GU_PrimPacked;

namespace HDK_Sample
{

/// Example of a simple packed primitive which has shared data
///
/// The primitive created has data which is shared between multiple primitives.
/// The shared data is saved out just one time to the .bgeo file and remains
/// shared after loading.
///
class GU_PackedSharedData : public GU_PackedImpl
{
public:
    GU_PackedSharedData();
    GU_PackedSharedData(const GU_PackedSharedData &src);
    ~GU_PackedSharedData() override;

    static void install(GA_PrimitiveFactory *factory);

    /// Get the type ID for the GU_PackedSharedData primitive type.
    static GA_PrimitiveTypeId typeId()
    {
        return theTypeId;
    }

    /// @{
    /// Virtual interface from GU_PackedImpl interface
    GU_PackedFactory   *getFactory() const override;
    GU_PackedImpl      *copy() const override;
    void                clearData() override;

    bool                isValid() const override;
    bool                load(GU_PrimPacked *prim,
                             const UT_Options &options,
                             const GA_LoadMap &loadmap) override
                        {
                            updateFrom(options, &loadmap);
                            return true;
                        }
    bool                supportsJSONLoad() const override { return true; }
    bool                loadFromJSON(
                                GU_PrimPacked *prim,
                                const UT_JSONValueMap &options,
                                const GA_LoadMap &loadmap) override
                        {
                            updateFrom(options, &loadmap);
                            return true;
                        }
    void                update(GU_PrimPacked *prim,
                               const UT_Options &options) override
                        {
                            updateFrom(options, nullptr);
                        }
    bool                save(UT_Options &options,
                             const GA_SaveMap &map) const override;
    bool                getBounds(UT_BoundingBox &box) const override;
    bool                getRenderingBounds(UT_BoundingBox &box) const override;
    void                getVelocityRange(
                                UT_Vector3 &min,
                                UT_Vector3 &max) const override;
    void                getWidthRange(fpreal &min, fpreal &max) const override;
    bool                unpack(GU_Detail &destgdp,
                               const UT_Matrix4D *transform) const override;

    /// Report memory usage (includes all shared memory)
    int64               getMemoryUsage(bool inclusive) const override;

    /// Count memory usage using a UT_MemoryCounter in order to count
    /// shared memory correctly.
    void                countMemory(UT_MemoryCounter &counter,
                                    bool inclusive) const override;
    /// @}

    /// @{
    /// Member data accessors for intrinsics
    UT_StringHolder     creationDate(const GU_PrimPacked *prim) const;
    UT_StringHolder     creationHost(const GU_PrimPacked *prim) const;
    /// @}

    /// Save shared primitive data
    bool                saveSharedData(
                                UT_JSONWriter &w,
                                GA_SaveMap &map,
                                GA_GeometryIndex *geo_index) const override;

    /// Information which is shared between multiple primitives
    struct SharedInfo
    {
        SharedInfo();
        UT_StringHolder myTimeStamp;    // Creation time
        UT_StringHolder myHostname;     // Creation host name
    };

protected:
    /// updateFrom() will update from either UT_Options or UT_JSONValueMap
    template <typename T>
    void        updateFrom(const T &options, const GA_LoadMap *loadmap);

private:
    /// Method to resolve the shared data
    bool                        resolveSharedData() const;

    /// The shared handle is used to keep a "handle" to the shared data.  This
    /// handle will be resolved on demand.
    mutable GA_SharedDataHandlePtr      mySharedHandle;
    /// Shared pointer to actual shared data for the primitive
    mutable UT_SharedPtr<SharedInfo>    mySharedInfo;

    static GA_PrimitiveTypeId theTypeId;
};

}       // End namespace

#endif