InferenceInstance

This function fills in values that are implicitely known but not given by the user. This function can also be used to identify default values of properties if not given.

Syntax

public const string EngineDLL = @"engine.dll";[DllImport(EngineDLL, EntryPoint = "InferenceInstance")]
public static extern Int64 InferenceInstance(Int64 owlInstance);    

Property owlInstance

Size: 64 bit / 8 byte (value)
The handle to the specific instance in the design tree. The instance handle is static within one open model but is most probably different when the same instance is opened in another model. The instance is always exactly of one unique class.

Example

Here you can find code snippits that show how the API call InferenceInstance can be used.

using Engine;

static void Main(string[] args)
{
    Int64 model = Engine.x86_64.CreateModel();

    if (model != 0)
    {
        Int64   classInverseMatrix = Engine.x86_64.GetClassByName(model, "InverseMatrix"),
                classMatrix = Engine.x86_64.GetClassByName(model, "Matrix");

        //
        //  Object Properties (relations)
        //
        Int64   propertyMatrix = Engine.x86_64.GetPropertyByName(model, "matrix");

        //
        //  Datatype Properties (attributes)
        //
        Int64   property_21 = Engine.x86_64.GetPropertyByName(model, "_21"),
                property_33 = Engine.x86_64.GetPropertyByName(model, "_33"),
                property_42 = Engine.x86_64.GetPropertyByName(model, "_42");

        //
        //  Instances (creating)
        //
        Int64   instanceInverseMatrix = Engine.x86_64.CreateInstance(classInverseMatrix, (string) null),
                instanceMatrix = Engine.x86_64.CreateInstance(classMatrix, (string) null);

        Engine.x86_64.SetObjectProperty(instanceInverseMatrix, propertyMatrix, ref instanceMatrix, 1);

        double  translationY = 2.8;

        Engine.x86_64.SetDatatypeProperty(instanceMatrix, property_42, ref translationY, 1);

        Int64   card = 0;
        IntPtr  valuesPtr = IntPtr.Zero;
        Engine.x86_64.GetDatatypeProperty(instanceMatrix, property_21, out valuesPtr, out card);
        System.Diagnostics.Debug.Assert(card == 0);

        Engine.x86_64.GetDatatypeProperty(instanceMatrix, property_33, out valuesPtr, out card);
        System.Diagnostics.Debug.Assert(card == 0);

        Engine.x86_64.GetDatatypeProperty(instanceInverseMatrix, property_42, out valuesPtr, out card);
        System.Diagnostics.Debug.Assert(card == 0);

        Engine.x86_64.GetDatatypeProperty(instanceInverseMatrix, property_33, out valuesPtr, out card);
        System.Diagnostics.Debug.Assert(card == 0);

        //
        //  Force to apply a calculation of the tree,
        //  CalculateInstance without further non-zero arguments has the same effect.
        //
        Engine.x86_64.UpdateInstance(instanceInverseMatrix);

        //
        //  Assign all implicitely known values
        //
        Engine.x86_64.InferenceInstance(instanceInverseMatrix);

        Engine.x86_64.GetDatatypeProperty(instanceMatrix, property_21, out valuesPtr, out card);
        System.Diagnostics.Debug.Assert(card == 1);
        if (card > 0)
        {
            double[] values = new double[card];
            System.Runtime.InteropServices.Marshal.Copy(valuesPtr, values, 0, (int) card);
            System.Diagnostics.Debug.Assert(values[0] == 0.0);
        }

        Engine.x86_64.GetDatatypeProperty(instanceMatrix, property_33, out valuesPtr, out card);
        System.Diagnostics.Debug.Assert(card == 1);
        if (card > 0)
        {
            double[] values = new double[card];
            System.Runtime.InteropServices.Marshal.Copy(valuesPtr, values, 0, (int) card);
            System.Diagnostics.Debug.Assert(values[0] == 1.0);
        }

        Engine.x86_64.GetDatatypeProperty(instanceInverseMatrix, property_42, out valuesPtr, out card);
        System.Diagnostics.Debug.Assert(card == 1);
        if (card > 0)
        {
            double[] values = new double[card];
            System.Runtime.InteropServices.Marshal.Copy(valuesPtr, values, 0, (int) card);
            System.Diagnostics.Debug.Assert(values[0] == -translationY);
        }

        Engine.x86_64.GetDatatypeProperty(instanceInverseMatrix, property_33, out valuesPtr, out card);
        System.Diagnostics.Debug.Assert(card == 1);
        if (card > 0)
        {
            double[] values = new double[card];
            System.Runtime.InteropServices.Marshal.Copy(valuesPtr, values, 0, (int) card);
            System.Diagnostics.Debug.Assert(values[0] == 1.0);
        }

        //
        //  The resulting model can be viewed in 3D-Editor.exe
        //
        Engine.x86_64.SaveModel(model, "c:\\created\\myFile.bin");
        Engine.x86_64.CloseModel(model);
    }
}