use SDL for timer.

OpenRa.FileFormats/OpenRa.FileFormats.csproj

@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 <Project DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003" ToolsVersion="3.5">
   <PropertyGroup>
     <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
@@ -50,6 +50,7 @@
       <SpecificVersion>False</SpecificVersion>
       <HintPath>..\thirdparty\Tao\Tao.Glfw.dll</HintPath>
     </Reference>
+    <Reference Include="Tao.Sdl, Version=1.2.13.0, Culture=neutral, PublicKeyToken=9c7a200e36c0094e, processorArchitecture=MSIL" />
   </ItemGroup>
   <ItemGroup>
     <Compile Include="AudLoader.cs" />

OpenRa.FileFormats/Support/Stopwatch.cs

@@ -20,12 +20,13 @@
 
 using System.Runtime.InteropServices;
 using Tao.Glfw;
+using Tao.Sdl;
 
 namespace OpenRa.Support
 {
 	public class Stopwatch
 	{
-		double start;
+		int start;
 		public Stopwatch()
 		{
 			Reset();
@@ -33,12 +34,12 @@ namespace OpenRa.Support
 
 		public double ElapsedTime()
 		{
-			return (Glfw.glfwGetTime() - start);
+			return (1.0/1000.0) * (double)(Sdl.SDL_GetTicks() - start);
 		}
 
 		public void Reset()
 		{
-			start = Glfw.glfwGetTime();
+			start = Sdl.SDL_GetTicks();
 		}
 	}
 }