public Dictionary<SurfaceRendererTarget,TinRendererDefinition> RendererDefinitions {get; set;}

{
  var tinCP_renderers = new TinLayerCreationParams(tinDataset)
  {
    Name = "My TIN layer",
    IsVisible = true
  };

  // define the node renderer - use defaults
  var node_rd = new TinNodeRendererDefinition();

  // define the face/surface renderer
  var face_rd = new TinFaceClassBreaksRendererDefinition();
  face_rd.ClassificationMethod = ClassificationMethod.NaturalBreaks;
  // accept default color ramp, breakCount

  // set up the renderer dictionary
  var rendererDict = new Dictionary<SurfaceRendererTarget, TinRendererDefinition>
{
  { SurfaceRendererTarget.Points, node_rd },
  { SurfaceRendererTarget.Surface, face_rd }
};

  // assign the dictionary to the creation params
  tinCP_renderers.RendererDefinitions = rendererDict;
  // Note: Needs QueuedTask to run
  {
    // create the layer
    var tinLayer_rd = LayerFactory.Instance.CreateLayer<TinLayer>(tinCP_renderers, MapView.Active.Map);
  }
}