From 5c140441388abe63da02d523ffc8464a93f68e73 Mon Sep 17 00:00:00 2001
From: RoosterDragon <RoosterDragon@outlook.com>
Date: Wed, 23 Dec 2015 22:58:53 +0000
Subject: [PATCH] Support sending sequences of points when drawing lines.

This allows the graph widgets to avoid having to create temporary arrays just to draw these lines, which reduces GC pressure.
---
 OpenRA.Game/Graphics/RgbaColorRenderer.cs     | 30 +++++++++++++------
 OpenRA.Mods.Common/Widgets/LineGraphWidget.cs |  2 +-
 OpenRA.Mods.Common/Widgets/PerfGraphWidget.cs |  2 +-
 3 files changed, 23 insertions(+), 11 deletions(-)

diff --git a/OpenRA.Game/Graphics/RgbaColorRenderer.cs b/OpenRA.Game/Graphics/RgbaColorRenderer.cs
index 860a8b1da5..55c4239d34 100644
--- a/OpenRA.Game/Graphics/RgbaColorRenderer.cs
+++ b/OpenRA.Game/Graphics/RgbaColorRenderer.cs
@@ -11,6 +11,7 @@
 using System;
 using System.Collections.Generic;
 using System.Drawing;
+using System.Linq;
 
 namespace OpenRA.Graphics
 {
@@ -109,6 +110,23 @@ namespace OpenRA.Graphics
 			return new float2(x, y) / d;
 		}
 
+		void DrawDisconnectedLine(IEnumerable<float2> points, float width, Color color)
+		{
+			using (var e = points.GetEnumerator())
+			{
+				if (!e.MoveNext())
+					return;
+
+				var lastPoint = e.Current;
+				while (e.MoveNext())
+				{
+					var point = e.Current;
+					DrawLine(lastPoint, point, width, color);
+					lastPoint = point;
+				}
+			}
+		}
+
 		void DrawConnectedLine(float2[] points, float width, Color color, bool closed)
 		{
 			// Not a line
@@ -178,18 +196,12 @@ namespace OpenRA.Graphics
 			}
 		}
 
-		public void DrawLine(float2[] points, float width, Color color, bool connectSegments = false)
+		public void DrawLine(IEnumerable<float2> points, float width, Color color, bool connectSegments = false)
 		{
 			if (!connectSegments)
-			{
-				if (points.Length < 2)
-					return;
-
-				for (var i = 1; i < points.Length; i++)
-					DrawLine(points[i - 1], points[i], width, color);
-			}
+				DrawDisconnectedLine(points, width, color);
 			else
-				DrawConnectedLine(points, width, color, false);
+				DrawConnectedLine(points as float2[] ?? points.ToArray(), width, color, false);
 		}
 
 		public void DrawPolygon(float2[] vertices, float width, Color color)
diff --git a/OpenRA.Mods.Common/Widgets/LineGraphWidget.cs b/OpenRA.Mods.Common/Widgets/LineGraphWidget.cs
index f79ca19c66..06cb7bd51d 100644
--- a/OpenRA.Mods.Common/Widgets/LineGraphWidget.cs
+++ b/OpenRA.Mods.Common/Widgets/LineGraphWidget.cs
@@ -127,7 +127,7 @@ namespace OpenRA.Mods.Common.Widgets
 							lastX = x;
 							lastPoint = point;
 							return origin + new float2(x * xStep, -point * scale);
-						}).ToArray(), 1, color);
+						}), 1, color);
 
 					if (lastPoint != 0f)
 						tiny.DrawText(GetValueFormat().F(lastPoint), origin + new float2(lastX * xStep, -lastPoint * scale - 2), color);
diff --git a/OpenRA.Mods.Common/Widgets/PerfGraphWidget.cs b/OpenRA.Mods.Common/Widgets/PerfGraphWidget.cs
index 483bfd199f..7d4e075877 100644
--- a/OpenRA.Mods.Common/Widgets/PerfGraphWidget.cs
+++ b/OpenRA.Mods.Common/Widgets/PerfGraphWidget.cs
@@ -37,7 +37,7 @@ namespace OpenRA.Mods.Common.Widgets
 			foreach (var item in PerfHistory.Items.Values)
 			{
 				cr.DrawLine(item.Samples()
-					.Select((sample, i) => origin + new float2(i, (float)sample) * basis).ToArray(),
+					.Select((sample, i) => origin + new float2(i, (float)sample) * basis),
 					1, item.C);
 
 				var u = new float2(rect.Left, rect.Top);