Added Application#getMainThread and related methods

Author: Anuken

arc-core/src/arc/Application.java

@@ -74,8 +74,21 @@ default long getNativeHeap(){
         return 0;
     }
 
-    @Nullable
-    String getClipboardText();
+    /** @return the main graphics thread, upon which all ApplicationListener methods are called. May return null if not initialized. */
+    default @Nullable Thread getMainThread(){
+        return null;
+    }
+
+    /**
+     * @return whether the currently executing thread is the main thread.
+     * If the main thread is not initialized, returns true by default. This is used for error checking purposes.
+     * */
+    default boolean isOnMainThread(){
+        Thread thread = getMainThread();
+        return thread == null || Thread.currentThread() == thread;
+    }
+
+    @Nullable String getClipboardText();
 
     void setClipboardText(String text);
 

arc-core/src/arc/mock/MockApplication.java

@@ -4,6 +4,7 @@
 import arc.struct.*;
 
 public class MockApplication implements Application{
+
     @Override
     public Seq<ApplicationListener> getListeners(){
         return new Seq<>();

backends/backend-android/src/arc/backend/android/AndroidApplication.java

@@ -41,6 +41,7 @@ public class AndroidApplication extends Activity implements Application{
     protected ClipboardManager clipboard;
     protected boolean useImmersiveMode = false;
     protected boolean hideStatusBar = false;
+    protected @Nullable Thread mainThread;
 
     static{
         ArcNativesLoader.load();
@@ -168,6 +169,11 @@ protected void hideStatusBar(boolean hide){
         getWindow().getDecorView().setSystemUiVisibility(0x1);
     }
 
+    @Override
+    public Thread getMainThread(){
+        return mainThread;
+    }
+
     @Override
     public void getDnsServers(Seq<InetSocketAddress> out){
         if(getVersion() < 21) return; //needs API level 21

backends/backend-android/src/arc/backend/android/AndroidGraphics.java

@@ -217,6 +217,7 @@ public void onSurfaceChanged(GL10 gl, int width, int height){
         updatePpi();
         gl.glViewport(0, 0, this.width, this.height);
         if(!created){
+            app.mainThread = Thread.currentThread();
             for(ApplicationListener list : app.getListeners()){
                 list.init();
             }

backends/backend-headless/src/arc/backend/headless/HeadlessApplication.java

@@ -103,6 +103,11 @@ void mainLoop(){
         }
     }
 
+    @Override
+    public Thread getMainThread(){
+        return mainLoopThread;
+    }
+
     @Override
     public ApplicationType getType(){
         return ApplicationType.headless;

backends/backend-robovm/src/arc/backend/robovm/IOSApplication.java

@@ -21,6 +21,7 @@ public class IOSApplication implements Application{
     IOSApplicationConfiguration config;
     IOSGraphics graphics;
     IOSInput input;
+    Thread mainThread;
     @Nullable IOSDevice device;
     float displayScaleFactor;
 
@@ -151,6 +152,11 @@ final void willTerminate(UIApplication uiApp){
         Gl.finish();
     }
 
+    @Override
+    public Thread getMainThread(){
+        return mainThread;
+    }
+
     @Override
     public ApplicationType getType(){
         return ApplicationType.iOS;

backends/backend-robovm/src/arc/backend/robovm/IOSGraphics.java

@@ -201,6 +201,7 @@ public void draw(GLKView view, CGRect rect){
         gl20.glViewport(IOSGLES20.x, IOSGLES20.y, IOSGLES20.width, IOSGLES20.height);
 
         if(!created){
+            app.mainThread = Thread.currentThread();
             gl20.glViewport(0, 0, width, height);
 
             String versionString = gl20.glGetString(GL20.GL_VERSION);

backends/backend-sdl/src/arc/backend/sdl/SdlApplication.java

@@ -24,6 +24,7 @@ public class SdlApplication implements Application{
     final SdlGraphics graphics;
     final SdlInput input;
     final SdlConfig config;
+    final Thread mainThread;
 
     boolean running = true;
     long window, context;
@@ -32,6 +33,8 @@ public SdlApplication(ApplicationListener listener, SdlConfig config){
         this.config = config;
         this.listeners.add(listener);
 
+        mainThread = Thread.currentThread();
+
         init();
 
         Core.app = this;
@@ -248,6 +251,11 @@ public long getWindow(){
         return window;
     }
 
+    @Override
+    public Thread getMainThread(){
+        return mainThread;
+    }
+
     @Override
     public boolean openFolder(String file){
         Threads.daemon(() -> {

extensions/profiling/src/arc/profiling/GL20Interceptor.java

@@ -2,7 +2,6 @@
 
 import arc.*;
 import arc.graphics.*;
-import arc.util.*;
 
 import java.nio.*;
 
@@ -12,16 +11,14 @@
  */
 public class GL20Interceptor extends GLInterceptor implements GL20{
     protected final GL20 gl20;
-    protected volatile @Nullable Thread mainThread;
 
     protected GL20Interceptor(GLProfiler glProfiler, GL20 gl20){
         super(glProfiler);
         this.gl20 = gl20;
-        Core.app.post(() -> mainThread = Thread.currentThread());
     }
 
     private void check(){
-        if(mainThread != null && Thread.currentThread() != mainThread){
+        if(!Core.app.isOnMainThread()){
             glProfiler.getListener().onError("GL call on wrong thread: " + Thread.currentThread());
         }
         int error = gl20.glGetError();

extensions/profiling/src/arc/profiling/GL30Interceptor.java

@@ -1,31 +1,24 @@
 package arc.profiling;
 
 import arc.*;
-import arc.graphics.GL20;
-import arc.graphics.GL30;
-import arc.util.*;
+import arc.graphics.*;
 
-import java.nio.Buffer;
-import java.nio.FloatBuffer;
-import java.nio.IntBuffer;
-import java.nio.LongBuffer;
+import java.nio.*;
 
 /**
  * @author Daniel Holderbaum
  * @author Jan Polák
  */
 public class GL30Interceptor extends GLInterceptor implements GL30{
     protected final GL30 gl30;
-    protected volatile @Nullable Thread mainThread;
 
     protected GL30Interceptor(GLProfiler glProfiler, GL30 gl30){
         super(glProfiler);
         this.gl30 = gl30;
-        Core.app.post(() -> mainThread = Thread.currentThread());
     }
 
     private void check(){
-        if(mainThread != null && Thread.currentThread() != mainThread){
+        if(!Core.app.isOnMainThread()){
             glProfiler.getListener().onError("GL call on wrong thread: " + Thread.currentThread());
         }
         int error = gl30.glGetError();