CameraRenderer.razor.cs

namespace Sandbox.UI.MapMonitor
{
	public partial class CameraRenderer : Panel
	{
		
		// Public properties
		public bool Static { get; set; } = false;
		public bool FullUpdateSceneCamera { get; set; } = false;
		public float LimitFrameRate { get; set; } = 30f;
		
		public bool Fullbright
		{
			get => _sceneCamera != null && _sceneCamera.AmbientLightColor == Color.Black;
			set
			{
				if ( _sceneCamera != null )
				{
					_sceneCamera.AmbientLightColor = new Color( 0.1f, 0.1f, 0.1f );
				}
			}
		}
		public SceneCamera? SceneCamera  => _sceneCamera;


		public CameraComponent? Camera
		{
			get => _camera;
			set
			{
				if(value != _camera)
				{
					SetCamera(value);
				}
			}
		}

		// Private fields
		private CameraComponent? _camera;
		private SceneCamera? _sceneCamera;
		private Texture _texture = Texture.Invalid;
		private TimeSince _lastRender = 0;
		
		// UI elements
		private Panel VideoPanel { get; set; } = null!;

		// Methods
		protected override void OnAfterTreeRender( bool firstTime )
		{
			if ( firstTime )
			{
				VideoPanel.Style.SetBackgroundImage( Texture.White );
				CreateTexture();
			}
		}

		public override void Tick()
		{
			if ( Camera == null )
				return;
			
			
			if ( LimitFrameRate < 0 || _lastRender > 1f / LimitFrameRate )
			{
				RenderToTexture();
				_lastRender = 0;
			}
		} 

		private void RenderToTexture()
		{
			if(_texture == Texture.Invalid)
			{
				_texture = CreateTexture();
				VideoPanel.Style.SetBackgroundImage( _texture );
			}
			if ( _sceneCamera != null && _texture != Texture.Invalid )
			{
				if ( FullUpdateSceneCamera && Camera.IsValid())
				{
					Camera.Enabled = true;
					Camera?.UpdateSceneCamera( _sceneCamera );
					Camera!.Enabled = false;
				}
				else if ( !Static && _sceneCamera != null && Camera != null)
				{
					_sceneCamera.Position = Camera.Transform.Position;
					_sceneCamera.Rotation = Camera.Transform.Rotation;
				}
				
				Graphics.RenderToTexture(_sceneCamera, _texture);
			}
			_lastRender = 0;
		}
		
		private Texture CreateTexture()
		{
			if(!VideoPanel.IsValid() || VideoPanel.Box.Rect.Size == Vector2.Zero)
				return Texture.Invalid;
			
			return Texture.CreateRenderTarget().WithSize( VideoPanel.Box.Rect.Size ).WithScreenFormat().WithScreenMultiSample().WithDynamicUsage().Create();
		}

		private void SetCamera( CameraComponent? camera )
		{
			_camera = camera;
			_sceneCamera ??= new SceneCamera();
			_camera?.UpdateSceneCamera( _sceneCamera ); 
			if(VideoPanel.IsValid())
				VideoPanel.Style.SetBackgroundImage( _texture );
		}
	}
};