Update the orientation of a graphic using expressions based on its attributes.
Use case
Instead of reading the attribute and changing the rotation on the symbol for a single graphic (a manual CPU operation), you can bind the rotation to an expression that applies to the whole overlay (an automatic GPU operation). This usually results in a noticeable performance boost (smooth rotations).
How to use the sample
Adjust the heading and pitch sliders to rotate the cone.
How it works
- Create a new graphics overlay.
- Create a simple renderer and set its scene properties.
- Set the heading expression to
[HEADING]. - Apply the renderer to the graphics overlay.
- Create a graphic and add it to the overlay.
- To update the graphic's rotation, update the HEADING or PITCH property in the graphic's attributes.
Relevant API
- Graphic.Attributes
- GraphicsOverlay
- SceneProperties
- SceneProperties.HeadingExpression
- SceneProperties.PitchExpression
- SimpleRenderer
- SimpleRenderer.SceneProperties
Tags
3D, expression, graphics, heading, pitch, rotation, scene, symbology
Sample Code
// Copyright 2019 Esri. // // Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. // You may obtain a copy of the License at: http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an // "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific // language governing permissions and limitations under the License. using Esri.ArcGISRuntime.Geometry; using Esri.ArcGISRuntime.Mapping; using Esri.ArcGISRuntime.Symbology; using Esri.ArcGISRuntime.UI; using Color = System.Drawing.Color; namespace ArcGIS.WPF.Samples.ScenePropertiesExpressions { [ArcGIS.Samples.Shared.Attributes.Sample( name: "Scene properties expressions", category: "GraphicsOverlay", description: "Update the orientation of a graphic using expressions based on its attributes.", instructions: "Adjust the heading and pitch sliders to rotate the cone.", tags: new[] { "3D", "expression", "graphics", "heading", "pitch", "rotation", "scene", "symbology" })] public partial class ScenePropertiesExpressions { public ScenePropertiesExpressions() { InitializeComponent(); Initialize(); } private void Initialize() { // Set up the scene with an imagery basemap. MySceneView.Scene = new Scene(BasemapStyle.ArcGISImageryStandard); // Set the initial viewpoint for the scene. MapPoint point = new MapPoint(83.9, 28.4, 1000, SpatialReferences.Wgs84); Camera initialCamera = new Camera(point, 1000, 0, 50, 0); MySceneView.SetViewpointCamera(initialCamera); // Create a graphics overlay. GraphicsOverlay overlay = new GraphicsOverlay(); overlay.SceneProperties.SurfacePlacement = SurfacePlacement.Relative; MySceneView.GraphicsOverlays.Add(overlay); // Add a renderer using rotation expressions. SimpleRenderer renderer = new SimpleRenderer(); renderer.SceneProperties.HeadingExpression = "[HEADING]"; renderer.SceneProperties.PitchExpression = "[PITCH]"; // Apply the renderer to the graphics overlay. overlay.Renderer = renderer; // Create a red cone graphic. SimpleMarkerSceneSymbol coneSymbol = SimpleMarkerSceneSymbol.CreateCone(Color.Red, 100, 100); coneSymbol.Pitch = -90; MapPoint conePoint = new MapPoint(83.9, 28.41, 200, SpatialReferences.Wgs84); Graphic cone = new Graphic(conePoint, coneSymbol); // Add the cone graphic to the overlay. overlay.Graphics.Add(cone); // Listen for changes in slider values and update graphic properties. HeadingSlider.ValueChanged += (sender, e) => { cone.Attributes["HEADING"] = HeadingSlider.Value; }; PitchSlider.ValueChanged += (sender, e) => { cone.Attributes["PITCH"] = PitchSlider.Value; }; } } }