moved the particle system and the entity component system into their own nuget packages

Source/MonoGame.Extended.Entities/Systems/SpriteBatchSystem.cs

@@ -0,0 +1,50 @@
+using Microsoft.Xna.Framework;
+using Microsoft.Xna.Framework.Graphics;
+using MonoGame.Extended.Entities.Components;
+using MonoGame.Extended.Particles;
+using MonoGame.Extended.Sprites;
+
+namespace MonoGame.Extended.Entities.Systems
+{
+    public class SpriteBatchSystem : ComponentSystem
+    {
+        private readonly Camera2D _camera;
+        private readonly SpriteBatch _spriteBatch;
+
+        public SpriteBatchSystem(GraphicsDevice graphicsDevice, Camera2D camera)
+        {
+            _camera = camera;
+            _spriteBatch = new SpriteBatch(graphicsDevice);
+        }
+
+        public Effect Effect { get; set; }
+        public RasterizerState RasterizerState { get; set; }
+        public DepthStencilState DepthStencilState { get; set; }
+        public SamplerState SamplerState { get; set; }
+        public BlendState BlendState { get; set; }
+        public SpriteSortMode SortMode { get; set; } = SpriteSortMode.Deferred;
+
+        public override void Draw(GameTime gameTime)
+        {
+            var spriteComponents = GetComponents<TransformableComponent<Sprite>>();
+            var particleEmitterComponents = GetComponents<TransformableComponent<ParticleEmitter>>();
+            var transformMatrix = _camera.GetViewMatrix();
+
+            _spriteBatch.Begin(SortMode, BlendState, SamplerState, DepthStencilState, RasterizerState, Effect, transformMatrix);
+
+            foreach (var spriteComponent in spriteComponents)
+            {
+                var sprite = spriteComponent.Target;
+                _spriteBatch.Draw(sprite);
+            }
+
+            foreach (var particleEmitterComponent in particleEmitterComponents)
+            {
+                var particleEmitter = particleEmitterComponent.Target;
+                _spriteBatch.Draw(particleEmitter);
+            }
+
+            _spriteBatch.End();
+        }
+    }
+}