[WorldWind学习]4.DrawArgs对象

 WorldWind的WorldWindow控件包含只读属性DrawArgs

public DrawArgs DrawArgs

        {

            get { return this.drawArgs; }

        }

DrawArgs渲染参数对象，负责记录当前渲染的各个参数

WorldWindow的CurrentWorld属性赋值时也给drawArgs的CurrentWorld赋值。

View Code

 1 public World CurrentWorld

 2         {

 3             get

 4             {

 5                 return m_World;

 6             }

 7             set

 8             {

 9                 m_World = value;

10                 if(m_World != null)

11                 {

12                     MomentumCamera camera = new MomentumCamera(m_World.Position, m_World.EquatorialRadius );

13                     if(!World.Settings.CameraResetsAtStartup)

14                     {

15                         camera.SetPosition(

16                             World.Settings.CameraLatitude.Degrees,

17                             World.Settings.CameraLongitude.Degrees,

18                             World.Settings.CameraHeading.Degrees, 

19                             World.Settings.CameraAltitude,

20                             World.Settings.CameraTilt.Degrees,

21                             0

22                             );

23                     }

24                     this.drawArgs.WorldCamera = camera;

25                     

26                     this.drawArgs.CurrentWorld = value;

27                     this.layerManagerButton = new LayerManagerButton(

28                         Path.Combine(Path.GetDirectoryName(Application.ExecutablePath), @"Data\Icons\Interface\layer-manager2.png"),

29                         m_World);

30                     

31                     this._menuBar.AddToolsMenuButton( this.layerManagerButton, 0 );

32                     this._menuBar.AddToolsMenuButton( new PositionMenuButton( Path.GetDirectoryName(Application.ExecutablePath) + "\\Data\\Icons\\Interface\\coordinates.png"), 1);

33                     this._menuBar.AddToolsMenuButton( new LatLonMenuButton( Path.GetDirectoryName(Application.ExecutablePath) + "\\Data\\Icons\\Interface\\lat-long.png", m_World), 2);

34                     this.layerManagerButton.SetPushed(World.Settings.ShowLayerManager);

35                     

36                     // TODO: Decide how to load grids

37                     m_World.RenderableObjects.Add(new Renderable.LatLongGrid(m_World));

38                 }

39             }

40         }

drawArgs的WorldCamera属性，注意DrawArgs类的public static CameraBase Camera = null;Camera是一个静态对象，具有缓存相机的作用。