Expand(Envelope,Double,Double,Double,Boolean) Method

Expands or shrinks the envelope in a 3-dimensional manner.

Syntax

C#
Visual Basic (Declaration)

Envelope Expand( 
   Envelope envelope,
   double dx,
   double dy,
   double dz,
   bool asRatio
)

Overloads Function Expand( _
   ByVal envelope As Envelope, _
   ByVal dx As Double, _
   ByVal dy As Double, _
   ByVal dz As Double, _
   ByVal asRatio As Boolean _
) As Envelope

Parameters

envelope: The envelope to expand or shrink.
dx: The scale factor along the x-axis. In other words, the amount to expand or shrink the width of the envelope.
dy: The scale factor along the y-axis. In other words, the amount to expand or shrink the height of the envelope.
dz: The scale factor along the z-axis. In other words, the amount to expand or shrink the depth of the envelope.
asRatio: If asRatio = false, the expansion is additive. If asRatio = true, the expansion is multiplicative.

Return Value

The scaled envelope.

Exceptions

Exception	Description
System.ArgumentNullException	Envelope is null or empty.
System.InvalidOperationException	This geometry is not Z-Aware.
System.NotImplementedException	Spatial reference of envelopeis an image coordinate system.

Remarks

The envelope must be z-aware or else an exception will be thrown.

If asRatio is set to true, dx, dy and dz must be greater than or equal to zero. In this case, if the user wants to increase the envelope width by 10%, then dx = 1.1. On the other hand, if the user wants to decrease the width by 10%, then dx = 0.9.

Example

Envelope env = EnvelopeBuilder.CreateEnvelope(100.0, 100.0, 500.0, 500.0);
// env.HasZ = false

Envelope result = GeometryEngine.Instance.Expand(env, 0.5, 0.5, true);
// result.Center = 300, 300
// result.XMin = 200
// result.YMin = 200
// result.XMax = 400
// result.YMax = 400

result = GeometryEngine.Instance.Expand(env, 100, 200, false);
// result.Center = 300, 300
// result.XMin = 0
// result.YMin = -100
// result.XMax = 600
// result.YMax = 700

try
{
  // expand in 3 dimensions
  result = GeometryEngine.Instance.Expand(env, 0.5, 0.5, 0.5, true);
}
catch (InvalidOperationException e)
{
  // the geometry is not Z-Aware
}

// expand a 3d envelope
MapPoint pt1 = MapPointBuilder.CreateMapPoint(100, 100, 100);
MapPoint pt2 = MapPointBuilder.CreateMapPoint(200, 200, 200);

env = EnvelopeBuilder.CreateEnvelope(pt1, pt2);
// env.HasZ = true
      
result = GeometryEngine.Instance.Expand(env, 0.5, 0.5, 0.5, true);

// result.Center = 150, 150, 150
// result.XMin = 125
// result.YMin = 125
// result.ZMin = 125
// result.XMax = 175
// result.YMax = 175
// result.ZMax = 175

Requirements

Target Platforms: Windows 10, Windows 8.1, Windows 7

Reference

IGeometryEngine Interface
IGeometryEngine Members
Overload List