Navisworks .NET API 2013 new feature – Viewpoint 2

By Xiaodong Liang

In the last post, we introduce the objects of viewpoint in .NET API. The API also allows you to manipulate the viewpoint. In general, we will need to manipulate current viewpoint. The current viewpoint is managed by the document part CurrentViewpoint. Same to other document part, we cannot modify it directly. The workflow is:

1) get the current viewpoint

2) create a copy from the current viewpoint

3) modify the properties of the copy

4) call CurrentViewpoint.CopyFrom with the copy

Following are some codes demos.

 

// change some general properties
privatevoid changeVPPro()
{
    Document oDoc =
        Autodesk.Navisworks.Api.Application.ActiveDocument;
 
    // get current viewpoint 
    Viewpoint oCurVP = oDoc.CurrentViewpoint;
    // get copy viewpoint
    Viewpoint oCopyVP = oCurVP.CreateCopy();
 
    oCopyVP.FarPlaneDistance *= 2;
    oCopyVP.NearPlaneDistance *= 2;
    if (oCopyVP.Tool != Tool.NavigateWalk)
        oCopyVP.Tool = Tool.NavigateWalk;
    oCopyVP.LinearSpeed *= 2;
    oCopyVP.AngularSpeed *= 2;
    if (oCopyVP.Projection != ViewpointProjection.Orthographic)
        oCopyVP.Projection = ViewpointProjection.Orthographic;
    if (oCopyVP.RenderStyle != ViewpointRenderStyle.Wireframe)
        oCopyVP.RenderStyle = ViewpointRenderStyle.Wireframe;
 
    //update the current viewpoint
    oDoc.CurrentViewpoint.CopyFrom(oCopyVP);
}
 
// move position of the camera 2 distance along X axis
privatevoid moveCameraPos()
{
    Document oDoc =
        Autodesk.Navisworks.Api.Application.ActiveDocument;
    // make a copy of current viewpoint
    Viewpoint oCurrVCopy = oDoc.CurrentViewpoint.CreateCopy();
    //step to move
    double step = 2;
    //  create the new position
    Point3D newPos =
        newPoint3D(oCurrVCopy.Position.X + step,   
                    oCurrVCopy.Position.Y,   
                    oCurrVCopy.Position.Z);
        oCurrVCopy.Position = newPos;
 
    // update current viewpoint
        oDoc.CurrentViewpoint.CopyFrom(oCurrVCopy);
 
}
 
// move position of the camera 2 along view direction
privatevoid moveCameraAlongViewDir()
{
    Document oDoc =
        Autodesk.Navisworks.Api.Application.ActiveDocument;
    // make a copy of current viewpoint
    Viewpoint oCurrVCopy = oDoc.CurrentViewpoint.CreateCopy();
    // get view direction
    Vector3D oViewDir = getViewDir(oCurrVCopy);
    //step to move
    double step = 2;
    //  create the new position
    Point3D newPos =
        newPoint3D(oCurrVCopy.Position.X + oViewDir.X * step,
                    oCurrVCopy.Position.Y + oViewDir.Y * step,
                    oCurrVCopy.Position.Z + oViewDir.Z * step);
    oCurrVCopy.Position = newPos;
 
    // update current viewpoint
    oDoc.CurrentViewpoint.CopyFrom(oCurrVCopy);
 
}
 
// change view direction
// set PointAt

privatevoid changeCameraViewDir_Way1()

{

    Document oDoc =

        Autodesk.Navisworks.Api.Application.ActiveDocument;

 

    // make a copy of current viewpoint

    Viewpoint oCurrVCopy = oDoc.CurrentViewpoint.CreateCopy();

    // Focal Distance

    double oFocal =

        oCurrVCopy.FocalDistance;

    Point3D oPos = oCurrVCopy.Position;

    // get current view direction

    Vector3D oViewDir = getViewDir(oCurrVCopy);

 

    //current target point (Loot At)

    Point3D oTarget =

        newPoint3D(oPos.X + oViewDir.X * oFocal,

                    oPos.Y + oViewDir.Y * oFocal,

                    oPos.Z + oViewDir.Z * oFocal);

 

    //step to move

    double step = 2;

 

    // new Point At

    Point3D newPointAt = newPoint3D(oTarget.X + step,

                                        oTarget.Y + step,

                                        oTarget.Z + step);

 

    // set to new target

    oCurrVCopy.PointAt(newPointAt );

// Note: when you set Point At, the position and focal 
    // do not change, while target (Look At) changes, i.e.
    // view direction changes.

    // update current viewpoint

    oDoc.CurrentViewpoint.CopyFrom(oCurrVCopy);

 

} 

//change view direction directly.

//note: will require combination of Position, Target and AlignUp

// in this demo: implement LEFT and RIGHT view

privatevoid changeCameraViewDir_Way2()

{

 

    Document oDoc =

             Autodesk.Navisworks.Api.Application.ActiveDocument;

 

    // make a copy of current viewpoint

    Viewpoint oCurrVCopy = oDoc.CurrentViewpoint.CreateCopy();

 

    // Focal Distance

    double oFocal =

        oCurrVCopy.FocalDistance;

 

    // new target is the center of the model

    Point3D oNewTarget = oDoc.Models[0].RootItem.BoundingBox().Center;

 

    //new direction is X- >> RIGHT

    Vector3D oNewViewDir = newVector3D(-1, 0, 0);

    //new direction is X >> LEFT

    //Vector3D oNewViewDir = new Vector3D(1, 0, 0);

 

    //calculate the new position by the target and focal distance

    Point3D oNewPos = newPoint3D(oNewTarget.X – oNewViewDir.X * oFocal,

        oNewTarget.Y – oNewViewDir.Y * oFocal,

        oNewTarget.Z – oNewViewDir.Z * oFocal);

 

    //set the position

    oCurrVCopy.Position = oNewPos;

    //set the target

    oCurrVCopy.PointAt(oNewTarget);

    //set view direction

    oCurrVCopy.AlignDirection(oNewViewDir);

    // set which direction is up: in this case it is Z+

    oCurrVCopy.AlignUp(newVector3D(0, 0, 1));

 

    // update current viewpoint

    oDoc.CurrentViewpoint.CopyFrom(oCurrVCopy);

}

 

// help function: get view direction

privateVector3D getViewDir(Viewpoint oVP)

{

    Rotation3D oRot = oVP.Rotation;

 

    // calculate view direction

    Rotation3D oNegtiveZ =

        newRotation3D(0, 0, -1, 0);

 

    Rotation3D otempRot =

        MultiplyRotation3D(oNegtiveZ, oRot.Invert());

 

    Rotation3D oViewDirRot =

        MultiplyRotation3D(oRot, otempRot);

 

    // get view direction

    Vector3D oViewDir =

        newVector3D(oViewDirRot.A,

                    oViewDirRot.B,

                    oViewDirRot.C);

 

    oViewDir.Normalize();

 

    returnnewVector3D(oViewDir.X,

                oViewDir.Y,

                oViewDir.Z);

 

}

 

 

// help function: Multiply two Rotation3D

privateRotation3D MultiplyRotation3D(

    Rotation3D r2,

    Rotation3D r1)

{

 

    Rotation3D oRot =

        newRotation3D(r2.D * r1.A + r2.A * r1.D +

                            r2.B * r1.C – r2.C * r1.B,

                        r2.D * r1.B + r2.B * r1.D +

                            r2.C * r1.A – r2.A * r1.C,

                        r2.D * r1.C + r2.C * r1.D +

                            r2.A * r1.B – r2.B * r1.A,

                        r2.D * r1.D – r2.A * r1.A –

                            r2.B * r1.B – r2.C * r1.C);

 

    oRot.Normalize();

 

    return oRot;

 

}