ArcGIS Pro 3.4 API Reference Guide
ArcGIS.Core.CIM Namespace / CIMPointCloudFixedSizeAlgorithm Class / Size Property
Example Version

Size Property (CIMPointCloudFixedSizeAlgorithm)
Gets or sets the size of the symbols.
Syntax
public double Size {get; set;}
Example
Edit The Renderer to use Fixed Size
//Must be called on the MCT
//var pcsl = ...;
var def = pcsl.GetDefinition() as CIMPointCloudLayer;

//Set the point shape and sizing on the renderer
def.Renderer.PointShape = PointCloudShapeType.DiskShaded;
var pointSize = new CIMPointCloudFixedSizeAlgorithm()
{
  UseRealWorldSymbolSizes = false,
  Size = 8
};
def.Renderer.PointSizeAlgorithm = pointSize;
//Commit changes back to the CIM
pcsl.SetDefinition(def);
Requirements

Target Platforms: Windows 11, Windows 10

ArcGIS Pro version: 3 or higher.
See Also