Various fixes and improvements

BNA/FNA.filter

@@ -45,6 +45,10 @@
 *.Input.Touch.TouchLocationState
 *.Input.Touch.TouchPanel
 *.Input.Touch.TouchPanelCapabilities
+*.Input.Keyboard
+*.Input.KeyboardState
+*.Input.Keys
+*.Input.KeyState
 
 *.Graphics.BasicEffect
 *.Graphics.Blend

BNA/src/Activity.cs

@@ -11,11 +11,45 @@ namespace Microsoft.Xna.Framework
 
         protected override void onCreate(android.os.Bundle savedInstanceState)
         {
+            // on some devices, this should be before call to base.onCreate
+            // requestWindowFeature(android.view.Window.FEATURE_NO_TITLE);
+
+            logTag = GetMetaAttr_Str("log.tag", "BNA_Game");
+
+            backKeyCode = GetMetaAttr_Int("back.key");
+
+            if (android.os.Build.VERSION.SDK_INT >= 19)
+            {
+                immersiveMode = GetMetaAttr_Int("immersive.mode") != 0;
+
+                if (immersiveMode && android.os.Build.VERSION.SDK_INT >= 28)
+                {
+                    var layoutParams = getWindow().getAttributes();
+                    layoutParams.layoutInDisplayCutoutMode =
+                        android.view.WindowManager.LayoutParams.LAYOUT_IN_DISPLAY_CUTOUT_MODE_SHORT_EDGES;
+                    getWindow().setAttributes(layoutParams);
+                }
+            }
+
+            if (GetMetaAttr_Int("keep.screen.on") != 0)
+            {
+                getWindow().addFlags(
+                    android.view.WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
+            }
+
+            /*
+            int flags = android.view.WindowManager.LayoutParams.FLAG_FULLSCREEN
+                      | android.view.WindowManager.LayoutParams.FLAG_DRAWS_SYSTEM_BAR_BACKGROUNDS
+                      | android.view.WindowManager.LayoutParams.FLAG_LAYOUT_IN_SCREEN
+                      | android.view.WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS;
+            if (GetMetaAttr_Int("keep.screen.on") != 0)
+                flags |= android.view.WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON;
+            getWindow().setFlags(flags
+                    | android.view.WindowManager.LayoutParams.FLAG_FORCE_NOT_FULLSCREEN,
+                                flags);
+            */
+
             base.onCreate(savedInstanceState);
-
-            _LogTag = GetMetaAttr("log.tag") ?? _LogTag;
-
-            new java.lang.Thread(gameRunner = new GameRunner(this)).start();
         }
 
         //
@@ -36,7 +70,7 @@ namespace Microsoft.Xna.Framework
 
         //
         // Android events forwarded to GameRunner:
-        // onPause, onResume, onDestroy, onTouchEvent
+        // onPause, onWindowFocusChanged, onDestroy, onTouchEvent, onBackPressed
         //
 
         protected override void onPause()
@@ -45,11 +79,39 @@ namespace Microsoft.Xna.Framework
             base.onPause();
         }
 
-        protected override void onResume()
+        public override void onWindowFocusChanged(bool hasFocus)
+        {
+            base.onWindowFocusChanged(hasFocus);
+
+            if (hasFocus)
+            {
+                if (immersiveMode)
+                {
+                    getWindow().getDecorView().setSystemUiVisibility(
+                              android.view.View.SYSTEM_UI_FLAG_LAYOUT_STABLE
+                            | android.view.View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
+                            | android.view.View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
+                            | android.view.View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
+                            | android.view.View.SYSTEM_UI_FLAG_FULLSCREEN
+                            | android.view.View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY);
+                }
+
+                if (object.ReferenceEquals(gameRunner, null))
+                {
+                    new java.lang.Thread(gameRunner = new GameRunner(this)).start();
+                }
+                else
+                {
+                    gameRunner.ActivityResume();
+                }
+            }
+        }
+
+        /*protected override void onResume()
         {
             gameRunner?.ActivityResume();
             base.onResume();
-        }
+        }*/
 
         protected override void onDestroy()
         {
@@ -79,33 +141,47 @@ namespace Microsoft.Xna.Framework
             return true;
         }
 
+        public override void onBackPressed()
+        {
+            if (backKeyCode != 0)
+                gameRunner?.ActivityKey(backKeyCode);
+            else
+                base.onBackPressed();
+        }
+
         //
-        // GetMetaAttr
+        // GetMetaAttr_Str, GetMetaAttr_Int
         //
 
-        public string GetMetaAttr(string name, bool warn = false)
+        public string GetMetaAttr_Str(string name, string def)
         {
-            var info = getPackageManager().getActivityInfo(getComponentName(),
+            name = "BNA." + name;
-                                    android.content.pm.PackageManager.GET_ACTIVITIES
+            var str = GetMetaData()?.getString(name);
-                                  | android.content.pm.PackageManager.GET_META_DATA);
-            name = "microsoft.xna.framework." + name;
-            var str = info?.metaData?.getString(name);
             if (string.IsNullOrEmpty(str))
             {
-                if (warn)
+                Activity.Log($"missing metadata attribute '{name}'");
-                    Activity.Log($"missing metadata attribute '{name}'");
+                str = def;
-                str = null;
             }
             return str;
         }
 
+        public int GetMetaAttr_Int(string name)
+            => GetMetaData()?.getInt("BNA." + name) ?? 0;
+
+        private android.os.Bundle GetMetaData()
+            => getPackageManager().getActivityInfo(
+                            getComponentName(),
+                            android.content.pm.PackageManager.GET_ACTIVITIES
+                          | android.content.pm.PackageManager.GET_META_DATA)
+                    ?.metaData;
+
         //
         // Log
         //
 
-        public static void Log(string s) => android.util.Log.i(_LogTag, s);
+        public static void Log(string s) => android.util.Log.i(logTag, s);
 
-        private static string _LogTag = "BNA_Game";
+        private static string logTag;
 
         //
         // data
@@ -113,6 +189,8 @@ namespace Microsoft.Xna.Framework
 
         private GameRunner gameRunner;
         private bool restartActivity;
+        private bool immersiveMode;
+        private int backKeyCode;
 
     }
 

BNA/src/Debug.cs

@@ -0,0 +1,13 @@
+
+namespace System.Diagnostics
+{
+
+    public static class Debug
+    {
+        public static void WriteLine(string message)
+        {
+            Microsoft.Xna.Framework.GameRunner.Log(message);
+        }
+    }
+
+}

BNA/src/Effect.cs

@@ -67,7 +67,7 @@ namespace Microsoft.Xna.Framework.Graphics
         public string CreateProgram2(string vertexText, string fragmentText)
         {
             string errText = null;
-            Renderer.Get(GraphicsDevice.GLDevice).Send( () =>
+            Renderer.Get(GraphicsDevice.GLDevice).Send(true, () =>
             {
                 (vertexId, errText) = CompileShader(
                             GLES20.GL_VERTEX_SHADER, "vertex", vertexText);
@@ -93,7 +93,6 @@ namespace Microsoft.Xna.Framework.Graphics
 
             (int, string) CompileShader(int kind, string errKind, string text)
             {
-                //GameRunner.Log($"SHADER PROGRAM: [[[" + text + "]]]");
                 string errText = null;
                 int shaderId = GLES20.glCreateShader(kind);
                 int errCode = GLES20.glGetError();
@@ -237,7 +236,7 @@ namespace Microsoft.Xna.Framework.Graphics
         public (string name, int type, int size)[] GetProgramUniforms()
         {
             (string, int, int)[] result = null;
-            Renderer.Get(GraphicsDevice.GLDevice).Send( () =>
+            Renderer.Get(GraphicsDevice.GLDevice).Send(true, () =>
             {
                 var count = new int[1];
                 GLES20.glGetProgramiv(programId, GLES20.GL_ACTIVE_UNIFORM_MAX_LENGTH, count, 0);
@@ -272,7 +271,7 @@ namespace Microsoft.Xna.Framework.Graphics
         public void INTERNAL_applyEffect(uint pass)
         {
             var graphicsDevice = GraphicsDevice;
-            Renderer.Get(graphicsDevice.GLDevice).Send( () =>
+            Renderer.Get(graphicsDevice.GLDevice).Send(false, () =>
             {
                 GLES20.glUseProgram(programId);
                 int n = Parameters.Count;
@@ -297,7 +296,7 @@ namespace Microsoft.Xna.Framework.Graphics
         {
             if (! base.IsDisposed)
             {
-                Renderer.Get(GraphicsDevice.GLDevice).Send( () =>
+                Renderer.Get(GraphicsDevice.GLDevice).Send(true, () =>
                 {
                     GLES20.glDeleteShader(fragmentId);
                     GLES20.glDeleteShader(vertexId);

BNA/src/FNA3D.cs

@@ -40,7 +40,7 @@ namespace Microsoft.Xna.Framework.Graphics
                 }
             }
 
-            Renderer.Get(device).Send( () =>
+            Renderer.Get(device).Send(false, () =>
             {
                 GLES20.glViewport(v.x, v.y, v.w, v.h);
                 GLES20.glDepthRangef(v.minDepth, v.maxDepth);
@@ -54,7 +54,7 @@ namespace Microsoft.Xna.Framework.Graphics
         public static void FNA3D_SetScissorRect(IntPtr device, ref Rectangle scissor)
         {
             var s = scissor;
-            Renderer.Get(device).Send( () =>
+            Renderer.Get(device).Send(false, () =>
             {
                 GLES20.glScissor(s.X, s.Y, s.Width, s.Height);
             });
@@ -69,7 +69,7 @@ namespace Microsoft.Xna.Framework.Graphics
         {
             var clearColor = color;
             var renderer = Renderer.Get(device);
-            renderer.Send( () =>
+            renderer.Send(false, () =>
             {
                 var state = (State) renderer.UserData;
                 var WriteMask = state.WriteMask;
@@ -180,8 +180,7 @@ namespace Microsoft.Xna.Framework.Graphics
             {
                 throw new PlatformNotSupportedException();
             }
-            var renderer = Renderer.Get(device);
+            Renderer.Get(device).Present();
-            renderer.Present();
         }
 
         //
@@ -192,7 +191,7 @@ namespace Microsoft.Xna.Framework.Graphics
         {
             var input = blendState;
             var renderer = Renderer.Get(device);
-            Renderer.Get(device).Send( () =>
+            Renderer.Get(device).Send(false, () =>
             {
                 var state = (State) renderer.UserData;
 
@@ -323,7 +322,6 @@ namespace Microsoft.Xna.Framework.Graphics
         public static void FNA3D_SetDepthStencilState(IntPtr device,
                                                       ref FNA3D_DepthStencilState depthStencilState)
         {
-            // AndroidActivity.LogI(">>>>> SET DEPTH AND STENCIL STATE");
         }
 
         //
@@ -335,7 +333,7 @@ namespace Microsoft.Xna.Framework.Graphics
         {
             var input = rasterizerState;
             var renderer = Renderer.Get(device);
-            Renderer.Get(device).Send( () =>
+            Renderer.Get(device).Send(false, () =>
             {
                 var state = (State) renderer.UserData;
 
@@ -382,6 +380,30 @@ namespace Microsoft.Xna.Framework.Graphics
             });
         }
 
+        //
+        // FNA3D_GetBackbufferSize
+        //
+
+        public static void FNA3D_GetBackbufferSize(IntPtr device, out int w, out int h)
+        {
+            var bounds = GameRunner.Singleton.ClientBounds;
+            w = bounds.Width;
+            h = bounds.Height;
+        }
+
+        //
+        // FNA3D_GetBackbufferSurfaceFormat
+        //
+
+        public static SurfaceFormat FNA3D_GetBackbufferSurfaceFormat(IntPtr device)
+        {
+            return SurfaceFormat.Color;
+        }
+
+        //
+        // FNA3D_GetMaxMultiSampleCount
+        //
+
         public static int FNA3D_GetMaxMultiSampleCount(IntPtr device, SurfaceFormat format,
                                                        int preferredMultiSampleCount)
         {
@@ -426,7 +448,7 @@ namespace Microsoft.Xna.Framework.Graphics
             int indexOffset = startIndex * elementSize;
             primitiveCount = PrimitiveCount(primitiveType, primitiveCount);
 
-            Renderer.Get(device).Send( () =>
+            Renderer.Get(device).Send(false, () =>
             {
                 GLES20.glBindBuffer(GLES20.GL_ELEMENT_ARRAY_BUFFER, (int) indices);
                 GLES30.glDrawRangeElements(drawMode, minVertexIndex, maxVertexIndex,
@@ -464,7 +486,7 @@ namespace Microsoft.Xna.Framework.Graphics
             int drawMode = PrimitiveTypeToDrawMode[(int) primitiveType];
             primitiveCount = PrimitiveCount(primitiveType, primitiveCount);
 
-            Renderer.Get(device).Send( () =>
+            Renderer.Get(device).Send(false, () =>
             {
                 GLES20.glDrawArrays(drawMode, vertexStart, primitiveCount);
             });

BNA/src/FNA3D_Buf.cs

@@ -30,7 +30,7 @@ namespace Microsoft.Xna.Framework.Graphics
         private static int CreateBuffer(Renderer renderer, int target, byte dynamic, int size)
         {
             int bufferId = 0;
-            renderer.Send( () =>
+            renderer.Send(true, () =>
             {
                 int[] id = new int[1];
                 GLES20.glGenBuffers(1, id, 0);
@@ -74,7 +74,7 @@ namespace Microsoft.Xna.Framework.Graphics
         public static void FNA3D_AddDisposeVertexBuffer(IntPtr device, IntPtr buffer)
         {
             var renderer = Renderer.Get(device);
-            renderer.Send( () =>
+            renderer.Send(true, () =>
             {
                 GLES20.glDeleteBuffers(1, new int[] { (int) buffer }, 0);
 
@@ -102,7 +102,7 @@ namespace Microsoft.Xna.Framework.Graphics
             var dataBuffer = BufferSerializer.Convert(
                                     dataPointer, dataLength, state, bufferId);
 
-            renderer.Send( () =>
+            renderer.Send(false, () =>
             {
                 GLES20.glBindBuffer(target, bufferId);
 
@@ -151,11 +151,18 @@ namespace Microsoft.Xna.Framework.Graphics
                                                                   int numBindings, byte bindingsUpdated,
                                                                   int baseVertex)
         {
+            /* skip if FNA says the bindings have not been updated
+            if (baseVertex == ((State) renderer.UserData).BaseVertex.getAndSet(baseVertex))
+            {
+                if (bindingsUpdated == 0)
+                    return;
+            }*/
+
             var bindingsCopy = new FNA3D_VertexBufferBinding[numBindings];
             for (int i = 0; i < numBindings; i++)
                 bindingsCopy[i] = bindings[i];
 
-            Renderer.Get(device).Send( () =>
+            Renderer.Get(device).Send(false, () =>
             {
                 int nextAttribIndex = 0;
                 foreach (var binding in bindingsCopy)
@@ -278,8 +285,8 @@ namespace Microsoft.Xna.Framework.Graphics
                 // we use GCHandle::FromIntPtr to convert that address to an object reference.
                 // see also:  system.runtime.interopservices.GCHandle struct in baselib.
                 int offset = (int) data;
-                newBuffer = Convert(GCHandle.FromIntPtr(data - offset).Target,
+                newBuffer = Convert2(GCHandle.FromIntPtr(data - offset).Target,
-                                    offset, length, oldBuffer);
+                                     offset, length, oldBuffer);
 
                 if (newBuffer != oldBuffer)
                 {
@@ -293,8 +300,8 @@ namespace Microsoft.Xna.Framework.Graphics
             }
 
 
-            public static java.nio.Buffer Convert(object data, int offset, int length,
+            private static java.nio.Buffer Convert2(object data, int offset, int length,
-                                                  java.nio.Buffer buffer)
+                                                    java.nio.Buffer buffer)
             {
                 if (data is short[])
                 {
@@ -491,6 +498,7 @@ namespace Microsoft.Xna.Framework.Graphics
         {
             public Dictionary<int, int[]> BufferSizeUsage = new Dictionary<int, int[]>();
             public Dictionary<int, java.nio.Buffer> BufferCache = new Dictionary<int, java.nio.Buffer>();
+            //public java.util.concurrent.atomic.AtomicInteger BaseVertex = new java.util.concurrent.atomic.AtomicInteger();
         }
 
     }

BNA/src/FNA3D_Dev.cs

@@ -27,20 +27,23 @@ namespace Microsoft.Xna.Framework.Graphics
                 default:                throw new ArgumentException("depthStencilFormat");
             }
 
+            int swapInterval = presentationParameters.presentationInterval switch
+            {
+                PresentInterval.Two       => 2,
+                PresentInterval.Immediate => 0,
+                // Default, One, or any other value:
+                _                         => 1
+            };
+
+            bool checkErrors = GameRunner.Singleton.CheckGlErrors();
+
             var device = Renderer.Create(GameRunner.Singleton.Activity,
                                          GameRunner.Singleton.OnSurfaceChanged,
-                                         8, 8, 8, 0, depthSize, stencilSize);
+                                         8, 8, 8, 0, depthSize, stencilSize,
+                                         swapInterval, checkErrors);
+
             FNA3D_ResetBackbuffer(device, ref presentationParameters);
             return device;
-
-            /*var renderer = Renderer.Get(device);
-            renderer.UserData = new State()
-            {
-                BackBufferWidth    = presentationParameters.backBufferWidth,
-                BackBufferHeight   = presentationParameters.backBufferHeight,
-                AdjustViewport     = // see also FNA3D_SetViewport
-                    (presentationParameters.displayOrientation == DisplayOrientation.Default)
-            };*/
         }
 
         //

BNA/src/FNA3D_Rt.cs

@@ -27,7 +27,7 @@ namespace Microsoft.Xna.Framework.Graphics
                 renderTargetsCopy[i] = renderTargets[i];
 
             var renderer = Renderer.Get(device);
-            renderer.Send( () =>
+            renderer.Send(false, () =>
             {
                 var state = (State) renderer.UserData;
                 if (state.TargetFramebuffer == 0)
@@ -99,7 +99,7 @@ namespace Microsoft.Xna.Framework.Graphics
                 throw new PlatformNotSupportedException();
 
             var renderer = Renderer.Get(device);
-            renderer.Send( () =>
+            renderer.Send(false, () =>
             {
                 GLES20.glBindFramebuffer(GLES30.GL_DRAW_FRAMEBUFFER, 0);
 
@@ -132,7 +132,7 @@ namespace Microsoft.Xna.Framework.Graphics
                 int texture = (int) renderTarget.texture;
 
                 var renderer = Renderer.Get(device);
-                renderer.Send( () =>
+                renderer.Send(false, () =>
                 {
                     int textureUnit = GLES20.GL_TEXTURE0 + renderer.TextureUnits - 1;
                     GLES20.glActiveTexture(textureUnit);
@@ -165,7 +165,7 @@ namespace Microsoft.Xna.Framework.Graphics
             int bufferId = 0;
 
             var renderer = Renderer.Get(device);
-            renderer.Send( () =>
+            renderer.Send(true, () =>
             {
                 var state = (State) renderer.UserData;
 
@@ -192,7 +192,7 @@ namespace Microsoft.Xna.Framework.Graphics
         public static void FNA3D_AddDisposeRenderbuffer(IntPtr device, IntPtr renderbuffer)
         {
             var renderer = Renderer.Get(device);
-            renderer.Send( () =>
+            renderer.Send(true, () =>
             {
                 GLES20.glDeleteRenderbuffers(1, new int[] { (int) renderbuffer }, 0);
             });
@@ -216,6 +216,8 @@ namespace Microsoft.Xna.Framework.Graphics
                                            int x, int y, int w, int h, int level,
                                            object dataObject, int dataOffset, int dataLength)
         {
+            int[] tempIntArray = null;
+
             java.nio.Buffer buffer = dataObject switch
             {
                 sbyte[] byteArray =>
@@ -224,10 +226,18 @@ namespace Microsoft.Xna.Framework.Graphics
                 int[] intArray =>
                     java.nio.IntBuffer.wrap(intArray, dataOffset / 4, dataLength / 4),
 
+                Color[] _ =>
+                    // GameRunner constructor sets the marshal size of Color to -1,
+                    // so we expect only negative or zero values here
+                    java.nio.IntBuffer.wrap(
+                        tempIntArray = new int[dataLength <= 0
+                                               ? (dataLength = -dataLength)
+                                               : throw new ArgumentException()]),
+
                 _ => throw new ArgumentException(dataObject?.GetType().ToString()),
             };
 
-            renderer.Send( () =>
+            renderer.Send(true, () =>
             {
                 var state = (State) renderer.UserData;
                 if (state.SourceFramebuffer == 0)
@@ -257,6 +267,16 @@ namespace Microsoft.Xna.Framework.Graphics
 
                 GLES20.glBindFramebuffer(GLES30.GL_READ_FRAMEBUFFER, 0);
             });
+
+            if (tempIntArray != null)
+            {
+                if (dataOffset > 0)
+                    throw new ArgumentException();
+                // convert int[] array from the GL call to a Color[] array
+                var colorArray = (Color[]) dataObject;
+                for (int i = 0; i < dataLength; i++)
+                    colorArray[i - dataOffset].PackedValue = (uint) tempIntArray[i];
+            }
         }
 
         //

BNA/src/FNA3D_Tex.cs

@@ -90,7 +90,7 @@ namespace Microsoft.Xna.Framework.Graphics
             }
 
             int textureId = 0;
-            renderer.Send( () =>
+            renderer.Send(true, () =>
             {
                 int id = CreateTexture(renderer, GLES20.GL_TEXTURE_2D, format, levelCount);
                 if (id != 0)
@@ -138,7 +138,7 @@ namespace Microsoft.Xna.Framework.Graphics
         public static void FNA3D_AddDisposeTexture(IntPtr device, IntPtr texture)
         {
             var renderer = Renderer.Get(device);
-            renderer.Send( () =>
+            renderer.Send(true, () =>
             {
                 GLES20.glDeleteTextures(1, new int[] { (int) texture }, 0);
 
@@ -165,10 +165,13 @@ namespace Microsoft.Xna.Framework.Graphics
                 int[] intArray =>
                     java.nio.IntBuffer.wrap(intArray, dataOffset / 4, dataLength / 4),
 
+                Color[] colorArray =>
+                    bufferFromColorArray(colorArray, dataOffset, dataLength),
+
                 _ => throw new ArgumentException(dataObject?.GetType().ToString()),
             };
 
-            renderer.Send( () =>
+            renderer.Send(false, () =>
             {
                 GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, textureId);
 
@@ -200,6 +203,20 @@ namespace Microsoft.Xna.Framework.Graphics
 
                 }
             });
+
+            java.nio.Buffer bufferFromColorArray(Color[] array, int offset, int length)
+            {
+                // GameRunner constructor sets the marshal size of Color to -1,
+                // so we expect only negative or zero values here
+                if (offset > 0 || length > 0)
+                    throw new ArgumentException();
+                // convert Color[] array into an int[] array for the GL call
+                length = -length;
+                var intArray = new int[length];
+                for (int i = 0; i < length; i++)
+                    intArray[i] = (int) array[i - offset].PackedValue;
+                return java.nio.IntBuffer.wrap(intArray);
+            }
         }
 
         public static void FNA3D_SetTextureData2D(IntPtr device, IntPtr texture,
@@ -344,7 +361,7 @@ namespace Microsoft.Xna.Framework.Graphics
             int textureId = (int) texture;
             var renderer = Renderer.Get(device);
 
-            renderer.Send( () =>
+            renderer.Send(false, () =>
             {
                 var state = (State) renderer.UserData;
                 var config = state.TextureConfigs[textureId];

BNA/src/GameRunner.cs

@@ -14,8 +14,6 @@ namespace Microsoft.Xna.Framework
 
         private Activity activity;
         private System.Collections.Hashtable dict;
-        private int clientWidth, clientHeight;
-        private Rectangle clientBounds;
         private bool recreateActivity;
 
         private java.util.concurrent.atomic.AtomicInteger inModal;
@@ -31,6 +29,9 @@ namespace Microsoft.Xna.Framework
 
         private const int CONFIG_EVENT = 1;
         private const int TOUCH_EVENT  = 2;
+        private const int KEY_EVENT    = 4;
+
+        private int eventKeyCode;
 
         //
         // constructor
@@ -40,7 +41,15 @@ namespace Microsoft.Xna.Framework
         {
             this.activity = activity;
 
-            UpdateConfiguration(false);
+            // in Bluebonnet, the following method is used to specify the
+            // size that Marshal.SizeOf should return for non-primitive types.
+            // this is used to enable Texture2D.GetData/SetData to accept
+            // Color[] arrays.  see also SetTextureData in FNA3D_Tex
+            System.Runtime.InteropServices.Marshal.SetComObjectData(
+                typeof(System.Runtime.InteropServices.Marshal),
+                typeof(Color), -1);
+
+            UpdateConfiguration();
 
             inModal       = new java.util.concurrent.atomic.AtomicInteger();
             shouldPause   = new java.util.concurrent.atomic.AtomicInteger();
@@ -71,6 +80,12 @@ namespace Microsoft.Xna.Framework
             set => inModal.set(value ? 1 : 0);
         }
 
+        //
+        // CheckGlErrors
+        //
+
+        public bool CheckGlErrors() => activity.GetMetaAttr_Int("check.gl.errors") != 0;
+
         //
         // Thread run() method
         //
@@ -103,6 +118,8 @@ namespace Microsoft.Xna.Framework
                 GameRunner.Log("========================================");
                 GameRunner.Log(e.ToString());
                 GameRunner.Log("========================================");
+                if (! object.ReferenceEquals(e.InnerException, null))
+                    e = e.InnerException;
                 System.Windows.Forms.MessageBox.Show(e.ToString());
             }
 
@@ -111,19 +128,13 @@ namespace Microsoft.Xna.Framework
             {
                 Type clsType = null;
 
-                var clsName = activity.GetMetaAttr("main.class", true);
+                var clsName = activity.GetMetaAttr_Str("main.class", ".Program");
-                if (clsName != null)
+                if (clsName[0] == '.')
-                {
+                    clsName = activity.getPackageName() + clsName;
-                    if (clsName[0] == '.')
+                clsType = System.Type.GetType(clsName, false, true);
-                        clsName = activity.getPackageName() + clsName;
-
-                    clsType = System.Type.GetType(clsName, false, true);
-                }
 
                 if (clsType == null)
-                {
                     throw new Exception($"main class '{clsName}' not found");
-                }
 
                 return clsType;
             }
@@ -131,7 +142,7 @@ namespace Microsoft.Xna.Framework
 
             void CallMainMethod(Type mainClass)
             {
-                var method = mainClass.GetMethod("Main");
+                var method = mainClass.GetMethod("Main") ?? mainClass.GetMethod("main");
                 if (method.IsStatic)
                 {
                     method.Invoke(null, new object[method.GetParameters().Length]);
@@ -150,6 +161,7 @@ namespace Microsoft.Xna.Framework
         public void MainLoop(Game game)
         {
             int pauseCount = 0;
+            bool clearKeys = false;
 
             while (game.RunApplication)
             {
@@ -197,12 +209,19 @@ namespace Microsoft.Xna.Framework
                         eventBits = shouldEvents.get();
 
                     if ((eventBits & CONFIG_EVENT) != 0)
-                        UpdateConfiguration(true);
+                        UpdateConfiguration();
 
                     if ((eventBits & TOUCH_EVENT) != 0)
                     {
                         Microsoft.Xna.Framework.Input.Mouse
-                                .HandleEvents(clientWidth, clientHeight);
+                            .HandleEvents((int) dict["width"], (int) dict["height"]);
+                    }
+
+                    if ((eventBits & KEY_EVENT) != 0)
+                    {
+                        Microsoft.Xna.Framework.Input.Keyboard.keys.Add(
+                                (Microsoft.Xna.Framework.Input.Keys) eventKeyCode);
+                        clearKeys = true;
                     }
                 }
 
@@ -211,6 +230,16 @@ namespace Microsoft.Xna.Framework
                 //
 
                 game.Tick();
+
+                //
+                // a simulated key is signalled during a single frame
+                //
+
+                if (clearKeys)
+                {
+                    clearKeys = false;
+                    Microsoft.Xna.Framework.Input.Keyboard.keys.Clear();
+                }
             }
 
             InModal = true;
@@ -263,12 +292,18 @@ namespace Microsoft.Xna.Framework
 
         public void ActivityPause()
         {
-            if (! InModal)
+            if (shouldResume.get() == 0)
             {
-                shouldPause.incrementAndGet();
+                Microsoft.Xna.Framework.Media.MediaPlayer.ActivityPauseOrResume(true);
-                waitForPause.block();
+                Microsoft.Xna.Framework.Audio.SoundEffect.ActivityPauseOrResume(true);
-                if (shouldExit.get() == 0)
+
-                    waitForPause.close();
+                if (! InModal)
+                {
+                    shouldPause.incrementAndGet();
+                    waitForPause.block();
+                    if (shouldExit.get() == 0)
+                        waitForPause.close();
+                }
             }
         }
 
@@ -279,7 +314,16 @@ namespace Microsoft.Xna.Framework
         public void ActivityResume()
         {
             if (shouldResume.compareAndSet(1, 0))
+            {
+                // force a call to UpdateConfiguration after main loop wakes up.
+                // this will not actually invoke callbacks if nothing has changed.
+                OnSurfaceChanged();
+
                 waitForResume.open();
+
+                Microsoft.Xna.Framework.Media.MediaPlayer.ActivityPauseOrResume(false);
+                Microsoft.Xna.Framework.Audio.SoundEffect.ActivityPauseOrResume(false);
+            }
         }
 
         //
@@ -308,6 +352,23 @@ namespace Microsoft.Xna.Framework
             }
         }
 
+        //
+        // ActivityKey
+        //
+
+        public void ActivityKey(int keyCode)
+        {
+            for (;;)
+            {
+                int v = shouldEvents.get();
+                if (shouldEvents.compareAndSet(v, v | KEY_EVENT))
+                {
+                    eventKeyCode = keyCode;
+                    break;
+                }
+            }
+        }
+
         //
         // OnSurfaceChanged
         //
@@ -326,26 +387,76 @@ namespace Microsoft.Xna.Framework
         // UpdateConfiguration
         //
 
-        void UpdateConfiguration(bool withCallback)
+        void UpdateConfiguration()
         {
-            var metrics = new android.util.DisplayMetrics();
+            var metrics = GetDisplayMetrics(activity);
-            activity.getWindowManager().getDefaultDisplay().getRealMetrics(metrics);
+            int width = metrics.widthPixels;
+            int height = metrics.heightPixels;
 
-            clientWidth  = metrics.widthPixels;
+            var dict = new System.Collections.Hashtable();
-            clientHeight = metrics.heightPixels;
-            clientBounds = new Rectangle(0, 0, clientWidth, clientHeight);
 
-            if (dict == null)
+            dict["width"]  = width;
-                dict = new System.Collections.Hashtable();
+            dict["height"] = height;
+            dict["dpi"]    = (int) ((metrics.xdpi + metrics.ydpi) * 0.5f);
 
-            // int dpi - pixels per inch
+            if (object.ReferenceEquals(this.dict, null))
-            dict["dpi"] = (int) ((metrics.xdpi + metrics.ydpi) * 0.5f);
-
-            if (withCallback)
             {
+                // on first call, set the dict without invoking callbacks
+                SetExtra(dict, width, height);
+                this.dict = dict;
+            }
+            else if (! DictsEqual(dict, this.dict))
+            {
+                SetExtra(dict, width, height);
+                this.dict = dict;
+
                 OnClientSizeChanged();
                 OnOrientationChanged();
             }
+
+
+            android.util.DisplayMetrics GetDisplayMetrics(android.app.Activity activity)
+            {
+                bool isMultiWindow = false;
+                if (android.os.Build.VERSION.SDK_INT >= 24)
+                    isMultiWindow = activity.isInMultiWindowMode();
+
+                var metrics = new android.util.DisplayMetrics();
+                var display = activity.getWindowManager().getDefaultDisplay();
+                if (! isMultiWindow)
+                {
+                    // getRealMetrics gets real size of the entire screen.
+                    // this is what we need in full screen immersive mode.
+                    display.getRealMetrics(metrics);
+                }
+                else
+                {
+                    // getMetrics gets the size of the split window, minus
+                    // window frames.  this is useful in multi-window mode.
+                    display.getMetrics(metrics);
+                }
+
+                return metrics;
+            }
+
+
+            bool DictsEqual(System.Collections.Hashtable dict1,
+                            System.Collections.Hashtable dict2)
+            {
+                foreach (var key in dict1.Keys)
+                {
+                    if (! dict1[key].Equals(dict2[key]))
+                        return false;
+                }
+                return true;
+            }
+
+
+            void SetExtra(System.Collections.Hashtable dict, int width, int height)
+            {
+                dict["bounds"] = new Rectangle(0, 0, width, height);
+                dict["openUri"] = (Action<string>) OpenUri;
+            }
         }
 
         //
@@ -359,11 +470,32 @@ namespace Microsoft.Xna.Framework
             return null;
         }
 
+        //
+        // OpenUri
+        //
+
+        private void OpenUri(string uri)
+        {
+            activity.runOnUiThread(((java.lang.Runnable.Delegate) (() =>
+            {
+                try
+                {
+                    activity.startActivity(
+                        new android.content.Intent(android.content.Intent.ACTION_VIEW,
+                            android.net.Uri.parse(uri)));
+                }
+                catch (Exception e)
+                {
+                    GameRunner.Log(e.ToString());
+                }
+            })).AsInterface());
+        }
+
         //
         // GameWindow interface
         //
 
-        public override Rectangle ClientBounds => clientBounds;
+        public override Rectangle ClientBounds => (Rectangle) dict["bounds"];
 
         public override string ScreenDeviceName => "Android";
 
@@ -374,8 +506,8 @@ namespace Microsoft.Xna.Framework
 
         public override DisplayOrientation CurrentOrientation
         {
-            get => (clientWidth < clientHeight) ? DisplayOrientation.Portrait
+            get => ((int) dict["width"] < (int) dict["height"])
-                                                : DisplayOrientation.LandscapeLeft;
+                        ? DisplayOrientation.Portrait : DisplayOrientation.LandscapeLeft;
             set
             {
                 bool portrait  = 0 != (value & DisplayOrientation.Portrait);
@@ -387,7 +519,7 @@ namespace Microsoft.Xna.Framework
                 else if (landscape && (! portrait))
                     r = android.content.pm.ActivityInfo.SCREEN_ORIENTATION_USER_LANDSCAPE;
                 else
-                    r = android.content.pm.ActivityInfo.SCREEN_ORIENTATION_FULL_USER;
+                    return;
                 activity.setRequestedOrientation(r);
             }
         }

BNA/src/Import.cs

@@ -201,6 +201,12 @@ namespace Microsoft.Xna.Framework.Input
         public int Y { get; set; }
         public ButtonState LeftButton { get; set; }
     }
+
+    [java.attr.Discard] // discard in output
+    public static class Keyboard
+    {
+        public static List<Keys> keys;
+    }
 }
 
 

BNA/src/MediaPlayer.cs

@@ -15,6 +15,7 @@ namespace Microsoft.Xna.Framework.Media
         [java.attr.RetainType] private static float volume;
         [java.attr.RetainType] private static bool muted;
         [java.attr.RetainType] private static bool looping;
+        [java.attr.RetainType] private static bool wasPlayingBeforeActivityPause;
 
         //
         // static constructor
@@ -283,6 +284,28 @@ namespace Microsoft.Xna.Framework.Media
             }
 
         }
+
+        //
+        // ActivityPauseOrResume
+        //
+
+        public static void ActivityPauseOrResume(bool pausing)
+        {
+            if (pausing)
+            {
+                if (State == MediaState.Playing)
+                {
+                    wasPlayingBeforeActivityPause = true;
+                    Pause();
+                }
+            }
+            else if (wasPlayingBeforeActivityPause)
+            {
+                wasPlayingBeforeActivityPause = false;
+                Resume();
+            }
+        }
+
     }
 
     //

BNA/src/Renderer.cs

@@ -20,6 +20,8 @@ namespace Microsoft.Xna.Framework.Graphics
         private android.os.ConditionVariable waitObject;
         private java.util.concurrent.atomic.AtomicInteger paused;
         private Action actionOnChanged;
+        private int swapInterval;
+        private bool checkErrors;
 
         public object UserData;
 
@@ -39,11 +41,14 @@ namespace Microsoft.Xna.Framework.Graphics
 
         private Renderer(android.app.Activity activity, Action onChanged,
                          int redSize, int greenSize, int blueSize,
-                         int alphaSize, int depthSize, int stencilSize)
+                         int alphaSize, int depthSize, int stencilSize,
+                         int swapInterval, bool checkErrors)
         {
             waitObject = new android.os.ConditionVariable();
             paused = new java.util.concurrent.atomic.AtomicInteger();
             actionOnChanged = onChanged;
+            this.swapInterval = swapInterval;
+            this.checkErrors = checkErrors;
 
             activity.runOnUiThread(((java.lang.Runnable.Delegate) (() =>
             {
@@ -55,7 +60,6 @@ namespace Microsoft.Xna.Framework.Graphics
                 surface.setRenderer(this);
                 surface.setRenderMode(android.opengl.GLSurfaceView.RENDERMODE_WHEN_DIRTY);
                 activity.setContentView(surface);
-
             })).AsInterface());
 
             // wait for one onDrawFrame callback, which tells us that
@@ -78,16 +82,21 @@ namespace Microsoft.Xna.Framework.Graphics
         // Send
         //
 
-        public void Send(Action action)
+        public void Send(bool wait, Action action)
         {
             Exception exc = null;
             if (paused.get() == 0)
             {
-                var cond = new android.os.ConditionVariable();
+                if (! waitObject.block(2000))
-                surface.queueEvent(((java.lang.Runnable.Delegate) (() =>
                 {
-                    var error = GLES20.glGetError();
+                    // see also Present().  a timeout here means that onDrawFrame
-                    if (error == GLES20.GL_NO_ERROR)
+                    // was never called, so the surface was probably destroyed.
+                    paused.compareAndSet(0, -1);
+                }
+                else
+                {
+                    var cond = wait ? new android.os.ConditionVariable() : null;
+                    surface.queueEvent(((java.lang.Runnable.Delegate) (() =>
                     {
                         try
                         {
@@ -97,18 +106,21 @@ namespace Microsoft.Xna.Framework.Graphics
                         {
                             exc = exc2;
                         }
-                        error = GLES20.glGetError();
+                        if (checkErrors)
-                    }
+                        {
-                    if (error != GLES20.GL_NO_ERROR)
+                            var error = GLES20.glGetError();
-                        exc = new Exception($"GL Error {error}");
+                            if (error != GLES20.GL_NO_ERROR)
-                    cond.open();
+                                exc = new Exception($"GL Error {error}");
-                })).AsInterface());
+                        }
-                cond.block();
+                        if (cond != null)
+                            cond.open();
+                    })).AsInterface());
+                    if (cond != null)
+                        cond.block();
+                }
             }
             if (exc != null)
-            {
                 throw new AggregateException(exc.Message, exc);
-            }
         }
 
         //
@@ -119,7 +131,19 @@ namespace Microsoft.Xna.Framework.Graphics
         {
             waitObject.close();
             surface.requestRender();
-            waitObject.block();
+
+            // GLSurfaceView runs queued events before checking if render
+            // was requested; but if the event queue is empty, it checks
+            // if render requested, then calls onDrawFrame().  thus the
+            // sequence of events is as follows:
+
+            // - Present() blocks waitObject and requests render
+            // - any events already queued by Send() are processed by
+            // GLSurfaceView, before it checks for a requested render.
+            // - Send() delays any new events until waitObject is opened.
+            // - OnDrawFrame() is called and opens waitObject, and when
+            // it returns to GLSurfaceView, the GL buffers are swapped.
+            // - with waitObject open, Send() queues new events.
         }
 
         //
@@ -132,6 +156,17 @@ namespace Microsoft.Xna.Framework.Graphics
             // if onSurfaceCreated is called while resuming from pause,
             // it means the GL context was lost
             paused.compareAndSet(1, -1);
+
+            // assign high priority to the rendering thread
+            java.lang.Thread.currentThread()
+                        .setPriority(java.lang.Thread.MAX_PRIORITY);
+
+            // set swap interval
+            if (swapInterval != 1)
+            {
+                var eglDisplay = EGL14.eglGetDisplay(EGL14.EGL_DEFAULT_DISPLAY);
+                EGL14.eglSwapInterval(eglDisplay, swapInterval);
+            }
         }
 
         [java.attr.RetainName]
@@ -188,7 +223,8 @@ namespace Microsoft.Xna.Framework.Graphics
 
         public static IntPtr Create(android.app.Activity activity, Action onChanged,
                                     int redSize, int greenSize, int blueSize,
-                                    int alphaSize, int depthSize, int stencilSize)
+                                    int alphaSize, int depthSize, int stencilSize,
+                                    int swapInterval, bool checkErrors)
         {
             for (;;)
             {
@@ -216,7 +252,8 @@ namespace Microsoft.Xna.Framework.Graphics
                         deviceId = deviceId,
                         renderer = new Renderer(activity, onChanged,
                                                 redSize, greenSize, blueSize,
-                                                alphaSize, depthSize, stencilSize),
+                                                alphaSize, depthSize, stencilSize,
+                                                swapInterval, checkErrors),
                         activity = new java.lang.@ref.WeakReference(activity),
                     });
 
@@ -290,7 +327,7 @@ namespace Microsoft.Xna.Framework.Graphics
             foreach (var renderer in GetRenderersForActivity(activity))
             {
                 renderer.surface.onPause();
-                renderer.paused.set(1);
+                renderer.paused.compareAndSet(0, 1);
             }
         }
 
@@ -304,9 +341,20 @@ namespace Microsoft.Xna.Framework.Graphics
             {
                 if (renderer.paused.get() != 0)
                 {
-                    renderer.waitObject.close();
+                    // we cannot use waitObject for resuming, because the surface
+                    // may have been destroyed between pause and resume, in which
+                    // case onDrawFrame would not get called.
+
+                    var cond = new android.os.ConditionVariable();
+                    renderer.surface.queueEvent(((java.lang.Runnable.Delegate) (
+                        () => cond.open() )).AsInterface());
+
                     renderer.surface.onResume();
-                    renderer.waitObject.block();
+                    if (! cond.block(2000))
+                    {
+                        // something is wrong if the queued event did not run
+                        return false;
+                    }
 
                     if (! renderer.paused.compareAndSet(1, 0))
                     {

BNA/src/SoundEffect.cs

@@ -264,6 +264,29 @@ namespace Microsoft.Xna.Framework.Audio
         public static float DistanceScale { get; set; }
         public static float DopplerScale { get; set; }
         public static float SpeedOfSound { get; set; }
+
+        //
+        // ActivityPauseOrResume
+        //
+
+        public static void ActivityPauseOrResume(bool pausing)
+        {
+            try
+            {
+                instancesLock.@lock();
+                int num = instancesList.size();
+                for (int idx = 0; idx < num; idx++)
+                {
+                    var instRef = (java.lang.@ref.WeakReference) instancesList.get(idx);
+                    ((SoundEffectInstance) instRef.get())?.ActivityPauseOrResume(pausing);
+                }
+            }
+            finally
+            {
+                instancesLock.unlock();
+            }
+        }
+
     }
 
 
@@ -279,6 +302,7 @@ namespace Microsoft.Xna.Framework.Audio
         [java.attr.RetainType] private android.media.AudioTrack track;
         [java.attr.RetainType] private float pitch, pan, volume;
         [java.attr.RetainType] private bool isLooped;
+        [java.attr.RetainType] private bool wasPlayingBeforeActivityPause;
 
         //
         // Constructor (for SoundEffect.CreateInstance)
@@ -595,6 +619,27 @@ namespace Microsoft.Xna.Framework.Audio
         public void Apply3D(AudioListener listener, AudioEmitter emitter) { }
         public void Apply3D(AudioListener[] listeners, AudioEmitter emitter) { }
 
+        //
+        // ActivityPauseOrResume
+        //
+
+        public void ActivityPauseOrResume(bool pausing)
+        {
+            if (pausing)
+            {
+                if (State == SoundState.Playing)
+                {
+                    wasPlayingBeforeActivityPause = true;
+                    Pause();
+                }
+            }
+            else if (wasPlayingBeforeActivityPause)
+            {
+                wasPlayingBeforeActivityPause = false;
+                Resume();
+            }
+        }
+
     }
 
 

Demo1/AndroidManifest.xml

@@ -7,6 +7,10 @@
     package="com.spaceflint.bluebonnet.xnademo1">
 
     <!-- API 18, GLES 3.0 -->
+    <!-- note that if testing in the Android emulator, you may need to add
+         the following line in your ~/.android/advancedFeatures.ini file:
+                GLESDynamicVersion=on
+    !-->
     <uses-sdk android:minSdkVersion="18" android:targetSdkVersion="29" />
     <uses-feature android:glEsVersion="0x00030000" android:required="true" />
 
@@ -15,7 +19,10 @@
 
     <application android:label="BNA_Demo1"
                  android:icon="@drawable/icon"
-                 android:isGame="true" >
+                 android:isGame="true"
+                 android:resizeableActivity="true"
+                 android:supportsPictureInPicture="true"
+                 >
 
         <!-- set android:screenOrientation if you need to lock orientation:
           https://developer.android.com/guide/topics/manifest/activity-element#screen -->
@@ -29,21 +36,38 @@
                   android:configChanges="orientation|screenSize|screenLayout|keyboardHidden"
                   android:immersive="true"
                   android:launchMode="singleTask"
+                  android:maxAspectRatio="9"
                   >
 
-          <!-- microsoft.xna.framework.log.tag sets the log identifier
+          <!-- the name of the main entrypoint class.  if starts with a dot,
-               for log messages printed via android.util.Log by the app.
+               then it is appended to the namespace specifies in the package
-               if omitted, the default is 'BNA_Game' -->
+               attribute.  the default is '.Program' -->
+            <meta-data android:name="BNA.main.class" android:value=".Program"/>
 
-            <meta-data android:name="microsoft.xna.framework.log.tag"
+          <!-- the log identifier for log messages printed via android.util.Log
-                       android:value="BNA_Demo1"/>
+               by the app.  the default is 'BNA_Game' -->
+            <meta-data android:name="BNA.log.tag" android:value="BNA_Demo1"/>
 
-          <!-- microsoft.xna.framework.main.class sets the name of the main
+          <!-- specifies whether to call glGetError() after every GL call.
-               or entrypoint class.  if starts with a dot, it is appended
+               non-zero value enables error checks, zero skips error checks.
-               to the namespace specifies in the package attribute. -->
+               this has a negative impact on performance, and is not recommended
+               in production builds.  the default is '0' -->
+            <meta-data android:name="BNA.check.gl.errors" android:value="0"/>
 
-            <meta-data android:name="microsoft.xna.framework.main.class"
+          <!-- specifies whether to disable screen timeout, if set to a non-zero
-                       android:value=".Program"/>
+               value.  the default is '0' -->
+            <meta-data android:name="BNA.keep.screen.on" android:value="0"/>
+
+          <!-- specifies whether to enable full screen immersive mode, if set
+               to a non-zero value.  the default is '0' -->
+            <meta-data android:name="BNA.immersive.mode" android:value="0"/>
+
+          <!-- specifies the key to signal, for one frame, when the back button
+               is pressed.  if omitted or specified as zero, default handling of
+               the back button occurs, which typically stops the activity.
+               Escape = Microsoft.Xna.Framework.Input.Keys.Escape = 27.
+               Back = Microsoft.Xna.Framework.Input.Keys.Back = 8. -->
+            <meta-data android:name="BNA.back.key" android:value="0"/>
 
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
@@ -51,6 +75,15 @@
             </intent-filter>
 
         </activity>
+
+        <meta-data android:name="android.max_aspect" android:value="9" />
+
     </application>
 
+    <supports-screens android:smallScreens="true"
+                      android:normalScreens="true"
+                      android:largeScreens="true"
+                      android:xlargeScreens="true"
+                      android:anyDensity="true" />
+
 </manifest>

MakeAPK.project

@@ -24,6 +24,7 @@
 
     APK_TEMP_DIR = directory where APK processing occurs
                 e.g. $(OutputDir)/MyGame/Debug/Content
+                IMPORTANT:  this directory will be deleted and recreated!
 
     KEYSTORE_FILE = path to a keystore file used in APK signing
 
@@ -33,8 +34,6 @@
 
     BLUEBONNET_EXE = path to Bluebonnet.exe program file
 
-    BLUEBONNET_JAR = path to Baselib.jar file from Bluebonnet
-
     ANDROID_JAR = path to Android.jar file, for desired API level
                 e.g. $(ANDROID_HOME)/android-28/android.jar
 

build_bna.bat

@@ -0,0 +1,24 @@
+@echo off
+if "%ANDROID_JAR%" == "" (
+    echo Missing environment variable ANDROID_JAR.
+    echo It should specify the full path to an Android.jar file in the platforms directory of the Android SDK.
+    goto :EOF
+)
+if "%FNA_DLL%" == "" (
+    echo Missing environment variable FNA_DLL.
+    echo It should specify the full path to the FNA.DLL file.
+    goto :EOF
+)
+if "%BLUEBONNET_EXE%" == "" (
+    echo Missing environment variable BLUEBONNET_EXE.
+    echo It should specify the full path to the Bluebonnet executable.
+    goto :EOF
+)
+
+echo ========================================
+echo Building BNA.  Command:
+echo MSBuild BNA -p:Configuration=Release
+echo ========================================
+MSBuild BNA -p:Configuration=Release
+
+:EOF