From c9991f08c5437e53ea71c175159e82f868819bd6 Mon Sep 17 00:00:00 2001
From: Harrison Deng <yunyangdeng@gmail.com>
Date: Fri, 11 Jan 2019 23:11:45 -0600
Subject: [PATCH] Primitive batch now works with strips.

---
 RecrownedAthenaeum/Render/PrimitiveBatch.cs | 26 ++++++++++-----------
 1 file changed, 12 insertions(+), 14 deletions(-)

diff --git a/RecrownedAthenaeum/Render/PrimitiveBatch.cs b/RecrownedAthenaeum/Render/PrimitiveBatch.cs
index cb532b3..eae9429 100644
--- a/RecrownedAthenaeum/Render/PrimitiveBatch.cs
+++ b/RecrownedAthenaeum/Render/PrimitiveBatch.cs
@@ -11,8 +11,8 @@ namespace RecrownedAthenaeum.Render
 {
     public class PrimitiveBatch : IDisposable
     {
-        VertexPositionColor[] vertices;
-        int MaxVertices { get { return vertices.Length; } }
+        List<VertexPositionColor> vertices;
+        int maxVertices;
         int bufferPosition;
         BasicEffect basicEffect;
         PrimitiveType primitiveType;
@@ -26,16 +26,16 @@ namespace RecrownedAthenaeum.Render
         /// </summary>
         /// <param name="graphicsDevice">The current graphics device being used.</param>
         /// <param name="camera">The current camera being used.</param>
-        /// <param name="verticesPerBatch">The amount of vertices every batch can hold before flushing. Default is 450.</param>
-        public PrimitiveBatch(GraphicsDevice graphicsDevice, Camera2D camera, int verticesPerBatch = 450)
+        /// <param name="verticesPerBatch">The amount of vertices every batch can hold before flushing. Default is 450. Should be changed to be the most optimal number if possible. Especially if using strip primitive types.</param>
+        public PrimitiveBatch(GraphicsDevice graphicsDevice, Camera2D camera, int verticesPerBatch = 500)
         {
             this.graphicsDevice = graphicsDevice ?? throw new ArgumentNullException("Graphics device can't be null.");
-
+            maxVertices = verticesPerBatch;
             basicEffect = new BasicEffect(graphicsDevice);
             basicEffect.VertexColorEnabled = true;
             basicEffect.View = camera.Matrix;
 
-            vertices = new VertexPositionColor[verticesPerBatch];
+            vertices = new List<VertexPositionColor>(verticesPerBatch);
         }
 
         /// <summary>
@@ -46,11 +46,12 @@ namespace RecrownedAthenaeum.Render
         {
             if (began) throw new InvalidOperationException("Begin is being called twice before being ended.");
             this.primitiveType = primitiveType;
-            this.verticesPerPrimitive = 0;
+            verticesPerPrimitive = 0;
             switch (primitiveType)
             {
                 case PrimitiveType.LineList: verticesPerPrimitive = 2; break;
                 case PrimitiveType.TriangleList: verticesPerPrimitive = 3; break;
+                default: verticesPerPrimitive = 1; break;
             }
 
             basicEffect.CurrentTechnique.Passes[0].Apply();
@@ -74,27 +75,24 @@ namespace RecrownedAthenaeum.Render
         public void AddVertex(Vector2 vertex, Color color)
         {
             if (!began) throw new InvalidOperationException("Begin needs to be called before adding vertex.");
-            if (bufferPosition + verticesPerPrimitive >= MaxVertices && (bufferPosition % MaxVertices == 0))
+            if (primitiveType != PrimitiveType.LineStrip && primitiveType != PrimitiveType.TriangleStrip && bufferPosition + verticesPerPrimitive >= maxVertices && (bufferPosition % maxVertices == 0))
             {
                 Flush();
             }
-
-            vertices[bufferPosition].Position = (new Vector3(vertex, 0));
-            vertices[bufferPosition].Color = color;
+            vertices[bufferPosition] = new VertexPositionColor(new Vector3(vertex, 0), color);
 
             bufferPosition++;
         }
 
         /// <summary>
-        /// Flushes the batch. Automatically called if required.
+        /// Flushes the batch. Automatically called if required if using <see cref="PrimitiveType.LineList"/> or <see cref="PrimitiveType.TriangleList"/>. Otherwise, manual flushing is required.
         /// </summary>
         public void Flush()
         {
             if (!began) throw new InvalidOperationException("Begin needs to be called before flushing.");
             if (bufferPosition == 0) return;
 
-            graphicsDevice.DrawUserPrimitives(primitiveType, vertices, 0, bufferPosition / verticesPerPrimitive);
-
+            graphicsDevice.DrawUserPrimitives(primitiveType, vertices.ToArray(), 0, bufferPosition / verticesPerPrimitive);
             bufferPosition = 0;
         }