DG Kernel (ActiveX) Documentation


Skip Navigation Links.
Start page
Quick Start
Search Page
Installation
What is new
Upgrading Native Apps
Licensing
Collapse ModelsModels
Models
Persistence
Model Properties
Collapse EntitiesEntities
Collapse GeometryGeometry
Geometry
Collapse BRepBRep
BRep Overview
BRep Geometry
Shapes
Curves
Surfaces
Faces
Wires
Edges
Compounds
Collapse MeshMesh
Mesh Geometry
Mesh
BRep to Mesh Conversion
Curve Geometry
Line Strips
Point Sets
Overlays
Collapse AttributesAttributes
Local Frame
Appearance
Texture
Properties of an Entity
Collapse Model ItemsModel Items
Items
3D Text
Smart Labels
View Points
Collapse MeasurementsMeasurements
Measurements
Persistent Measurements
Grid
Collapse Operations and AlgorithmsOperations and Algorithms
Boolean Operations
Euclidean Shortest Path
Collapse MovementMovement
Movements
Kinematic Entities
Collision Detection
Collapse Import/ExportImport/Export
Import/Export Overview
Data Flow Sample
STL Tree
Collapse DG Kernel ControlsDG Kernel Controls
Components
DG Kernel Control
Collapse Properies, Methods, EventsProperies, Methods, Events
Properies
Methods
Events
Collapse Interactive FunctionalityInteractive Functionality
View
Context Menu
Measurements
Direct User Access
Modes of DG Kernel
Current Entities
Collapse Selection OverviewSelection Overview
Selection
Selection Event
Collapse Auxiliary ViewsAuxiliary Views
Model Explorer
Birds Eye View
Full Screen window
Collapse Programmatic FunctionalityProgrammatic Functionality
Programming
Queries
Data Types
Object Construction
Generator
Component Context
Initialisation Context
Collapse API ReferenceAPI Reference
Interface List
Vector Space
Collapse General GeometryGeneral Geometry
IPointArray_DG
IPointMatrix_DG
IPointCloud_DG
Collapse CurvesCurves
ICurve_DG
ILine_DG
ICircle_DG
IEllipse_DG
IBSplineCurve_DG
IBSplineCurveInterpolator_DG
ICurveFreeForm_DG
IArcSpline3DCurve_DG
Collapse 2D2D
ICurve2d_DG
IBSplineCurve2d_DG
ICircle2d_DG
ILine2d_DG
IArc_DG
Collapse SurfacesSurfaces
IUVSurface_DG
IPartialSplineProps_DG
IBSplineSurface_DG
IBezierSurface_DG
IPartialBezierProps_DG
IRectangularTrimmedSurface_DG
ISurfaceOfRevolution_DG
Collapse Oriented ObjectsOriented Objects
IObjectOriented_DG
IPlane_DG
ISphere_DG
ICylinder_DG
ICone_DG
ITorus_DG
IBox_DG
IPolygon3D_DG
IGeometricObject_DG
Collapse GeneralGeneral
IElement_DG
IStrip_DG
Collapse ModelModel
IModel_DG
Collapse EntitiesEntities
IEntity_DG
IEntityArray_DG
IStdShape_DG
IStdShapeRef_DG
IDraw_DG
IEntity2d_DG
IModel2d_DG
Collapse GeometryGeometry
IGeometry_DG
IPointSetGeometry_DG
ISegmentStripGeometry_DG
ICurveGeometry_DG
ISurfacePoint_DG
ISurfacePointArray_DG
ILabel_DG
ILabelGeometry_DG
ISticky_DG
Collapse BSpline BRep GeometryBSpline BRep Geometry
Collapse Advanced AlgorithmsAdvanced Algorithms
IBRepChamfer_DG
IBRepDraftAngle_DG
IBRepFillet_DG
IFeaturePrism_DG
IBRepShape_DG
IBRepVertex_DG
IBRepEdge_DG
IBRepWire_DG
IBRepFace_DG
IBRepShell_DG
IBRepSolid_DG
IBRepCompositeSolid_DG
IBRepCompound_DG
IShapeArray_DG
IBRepBuilderEx_DG
IWireArrayToSurfaceBuilder_DG
IBRepGeometry_DG
IBRepBuilder_DG
Collapse Mesh GeometryMesh Geometry
IMesh_DG
IMeshGeometry_DG
IVertex_DG
IVertexSegment_DG
ISimplex_DG
IMeshPoint_DG
IMeshAlgor_DG
IDiffSurface_DG
Collapse AppearenceAppearence
IAppearance_DG
IColor
IMaterial_DG
ITexture_DG
ILineStyle_DG
Collapse MovementMovement
Collapse Collision DetectionCollision Detection
IMetrics_DG
IPathCollisionDetector_DG
IKinematicEntity_DG
IMove_DG
IKinematicSet_DG
ICutEffect_DG
ISpinEffect_DG
IConstraint_DG
Collapse ItemsItems
IModelItem_DG
IItemArray_DG
IDynamicScreenItem_DG
IDynamicScreenItemManager_DG
ISmartLabelManager_DG
Collapse Import / ExportImport / Export
IDataContext_DG
ISTLDataContext_DG
Collapse Operations and AgorithmsOperations and Agorithms
IBooleanEntity_DG
IEuclideanShortestPath_DG
Collapse User DataUser Data
IUserData_DG
Collapse ViewView
IView_DG
ISelection_DG
IScene_DG
ILighting_DG
ILightSource_DG
IViewPoint_DG
IViewPointArray_DG
IMeasurement_DG
IRectangleColor_DG
I2DEditor_DG
IVirtualView_DG
Collapse General ComputingGeneral Computing
IObjectGenerator_DG
IControlInitialisationContext_DG
IGlobalAPI_DG
Collections
IUnknown
IObject_DG
IBitmap_DG
IBlob_DG
IContext_DG
IError_DG
IKCStack
IMenu_KC
IMenuItem_KC
IText
IFont_DG
Collapse ViewsViews
View
Scene
Global Axes
Background
3D Background
Collapse Samples and TutorialsSamples and Tutorials
Sample List
.NET Samples
Delphi and C++ Samples
Collapse GraphicsGraphics
Concepts
3D View
Viewing Volume
Eye Frame
Perspective View
Collapse Math ObjectsMath Objects
Mathematical Objects
Planes
Frames
Transforms
Oriented Objects
Boxes
Collapse CurvesCurves
Curve Technologies
Native Curves
Collapse 2D Elements2D Elements
Geometric Elements
Arcs
Line Strips
Collapse DeprecatedDeprecated
Collapse Deprecated GeometryDeprecated Geometry
Collapse 3DS3DS
Profiles
Surface Patches
Surfaces and Patch Strips
Input Validation
Collapse Lines and CurvesLines and Curves
3DS Curves
Surface Of Revolution
Collapse Deprecated API ReferenceDeprecated API Reference
Collapse ModelModel
Collapse SectionSection
IBoundary
Collapse 3DS3DS
IProfiles
IProfiledElement_KC
Redistribution
Model Viewer
Open Source
Support
Skip Navigation Links Go to DGKC docs Search Documentation


SAFEARRAY data type

SAFEARRAY data type described below is recognized by most development environments. It is used by DG Kernel software to pass references to buffers of data to and from the user application. The structure is described blow. Normally in Microsoft Visual Studio it should not be created directly. Use SafeArrayCreate() function (See online documentation for Visual Studio) to allocate the array. Then use SafeArrayLock() to access the data in the array. Use SafeArrayUnlock() and SafeArrayDestroy() to release and delete the data.

Sample below uses IModel_DG::SaveToMemory1() method to obtain copy of persistent data of the current model as a SAFEARRAY.

void MyDialog::DoSave(CADFormat_DG format) 
{
    IModel_DGPtr iModel = m_dgk.GetModel();

    SAFEARRAY* data = nullptr;

    iModel->SaveToMemory1(format, &data); // SaveToMemory() returns the array unlocked with zero lock counter

    // Access the data in the array
    VERIFY( SafeArrayLock(data) == S_OK );

    // At this point data of the model is located at data->pvData and has length of 
    // data->rgsabound[0].cElements bytes. Do embedding the model into the application document,
    // If the format is other than .MDG it might make sense to encrypt the data to keep you models 
    // accessible by your applications only

    // Unlock the data
    VERIFY( SafeArrayUnlock(data) == S_OK );
    // Release the memory
    VERIFY( SafeArrayDestroy(data) == S_OK );
}

Sample below uses IModel_DG::LoadFromMemory1() method to reload the current model from data in a SAFEARRAY.

void MyDialog::DoLoad(int format) 
{
    IModel_DGPtr iModel = m_dgk.GetModel();

    SAFEARRAYBOUND rgsabound[1];         // One dimensional array
    rgsabound[0].lLbound = 0;                           // The lower bound is always 0
    rgsabound[0].cElements = myModelSize;     // myModelSize would be same as file.GetLength(); 
                                                                        // if the model was loaded from a model file
    // Create array of the above size
    SAFEARRAY* psa = SafeArrayCreate(VT_UI1, 1, rgsabound);

    if(psa == NULL)
        return;

    VERIFY( SafeArrayLock( psa ) == S_OK );     // Before this call the data in psa->pvData is not accessible  

    //Copy, load etc data of the model from your application into psa->pvData here

    VARIANT_BOOL success = VARIANT_FALSE;
    iModel->LoadFromMemory(format, &psa, &success);     // Pass it to the component
    ASSERT(success == VARIANT_TRUE);
    VERIFY( SafeArrayUnlock( psa ) == S_OK );     // Unlock the data/> &nbs    VERIFY( SafeArrayDestroy( psa ) == S_OK );     // Release the memory
}

This is  how the SAFEARRAY type is described in Microsoft SDK documentation:

The definition for a safearray varies, depending on the target operating system platform. On 32-bit Windows systems, both the cbElements and cLocks parameters are unsigned long integers, and the handle parameter is omitted. On 16-bit Windows systems, cbElements and cLocks are unsigned short integers The handle parameter is retained for compatibility with earlier software. For example:

typedef struct FARSTRUCT tagSAFEARRAY {

        unsigned short cDims; // Count of dimensions in this array.

        unsigned short fFeatures; // Flags used by the SafeArray. routines documented below.

        unsigned long cbElements; // Size of an element of the array.  Does not include size of pointed-to data.

        unsigned long cLocks; // Number of times the array has been. Locked without corresponding unlock.

        void HUGEP* pvData; // Pointer to the data.

        SAFEARRAYBOUND rgsabound[1]; // One bound for each dimension.

} SAFEARRAY;

Remarks
The array rgsabound is stored with the left-most dimension in rgsabound[0] and the right-most dimension in rgsabound[cDims - 1]. If an array was specified in a C-like syntax as a [2][5], it would have two elements in the rgsabound vector. Element 0 has an lLbound of 0 and a cElements of 2. Element 1 has an lLbound of 0 and a cElements of 5.

The fFeatures flags describe attributes of an array that can affect how the array is released. The fFeatures field describes what type of data is stored in the SAFEARRAY and how the array is allocated. This allows freeing the array without referencing its containing variant. The bits are accessed using the following constants:

fFeatures Flags Description 

FADF_AUTO 0x0001 An array that is allocated on the stack.

FADF_STATIC 0x0002 An array that is statically allocated.

FADF_EMBEDDED 0x0004 An array that is embedded in a structure.

FADF_FIXEDSIZE 0x0010 An array that may not be resized or reallocated.

FADF_RECORD 0x0020    An array containing records. When set there will be a pointer to the IRecordinfo interface at negative offset 4 in the array descriptor.

FADF_HAVEIID 0x0040    An array that has an IID identifying interface. When set there will be a guid at negative offset 16 in the safearray descriptor. Flag is set only when FADF_DISPATCH or FADF_UNKNOWN is also set. 

FADF_HAVEVARTYPE 0x0080    An array that has a VT type. When set there will be a VT tag at negative offset 4 in the array descriptor that specifies the element type.

FADF_BSTR 0x0100    An array of BSTRs.

FADF_UNKNOWN 0x0200    An array of IUnknown*.

FADF_DISPATCH 0x0400    An array of IDispatch*.

FADF_VARIANT 0x0800    An array of VARIANTs.

FADF_RESERVED 0xF0E8    Bits reserved for future use.

SAFEARRAYBOUND Structure

typedef struct tagSAFEARRAYBOUND {

        unsigned long cElements;
        long lLbound;

} SAFEARRAYBOUND;