more with method naming, add XML hasChildren() method

android/core/src/processing/core/PApplet.java

@@ -7210,6 +7210,16 @@ public class PApplet extends Activity implements PConstants, Runnable {
   }
 
 
+  public PGL beginGL() {
+    return g.beginGL();
+  }
+
+
+  public void endGL() {
+    g.endGL();
+  }
+
+
   /**
    * Enable a hint option.
    * <P>

android/core/src/processing/core/PGraphics.java

@@ -25,6 +25,7 @@ package processing.core;
 
 import java.util.HashMap;
 
+import processing.opengl.PGL;
 import processing.opengl.PShader;
 
 import android.graphics.Bitmap;
@@ -675,6 +676,17 @@ public class PGraphics extends PImage implements PConstants {
   public void flush() {
     // no-op, mostly for P3D to write sorted stuff
   }
+  
+  
+  public PGL beginGL() {
+    showMethodWarning("beginGL");
+    return null;
+  }
+
+
+  public void endGL() {
+    showMethodWarning("endGL");
+  }
 
 
   protected void checkSettings() {

android/core/src/processing/data/XML.java

@@ -238,6 +238,12 @@ public class XML implements Serializable {
     checkChildren();
     return children.length;
   }
+  
+  
+  public boolean hasChildren() {
+    checkChildren();
+    return children.length > 0;
+  }
 
 
   /**

android/core/src/processing/opengl/PGraphicsOpenGL.java

@@ -1729,18 +1729,18 @@ public class PGraphicsOpenGL extends PGraphics {
   }
 
 
-  public PGL beginPGL() {
+  public PGL beginGL() {
     flush();
     return pgl;
   }
 
 
-  public void endPGL() {
+  public void endGL() {
     restoreGL();
   }
 
 
-  public void restartPGL() {
+  protected void restartPGL() {
     pgl.initialized = false;
   }