Fix BuildComposablePipeline's isGL*/getGL* ; GLBase: getDownstreamGL()/getRootGL(); GLContext.isGL* added proper API doc., isGL3core()/hasNoDefaultVAO() and getDefaultVAO().

- Fix BuildComposablePipeline's isGL*/getGL* (regression of commit 3a0d7703da32e9a5ddf08a334f18588a78038d880)

- GLBase: getDownstreamGL()/getRootGL()
  Allows user traversing through pipelined GL instances.
  Also added getRootGL() to GLContext.

- GLContext.isGL* added proper API doc.: We test the actual context, not the profile.

- GLContext isGL3core()/hasNoDefaultVAO() and getDefaultVAO()
  - Move isGL3code() def. back to pre 3a0d7703da32e9a5ddf08a334f18588a78038d880, i.e. Includes [ GL4, GL3 ] w/o GLES3.
  - Added hasNoDefaultVAO() and getDefaultVAO() .. incl. [ GL4, GL3, GLES3 ]

2 files changed, 160 insertions, 32 deletions

diff --git a/src/jogl/classes/javax/media/opengl/GLBase.java b/src/jogl/classes/javax/media/opengl/GLBase.java
index 49c5bf72d..fcfe34132 100644
--- a/src/jogl/classes/javax/media/opengl/GLBase.java
+++ b/src/jogl/classes/javax/media/opengl/GLBase.java
@@ -88,35 +88,41 @@ public interface GLBase {
   /**
    * Indicates whether this GL object conforms to the OpenGL ≥ 4.0 compatibility profile.
    * The GL4 compatibility profile includes the GL2, GL2ES1, GL2ES2, GL3, GL3bc and GL4 profile.
+   * @see GLContext#isGL4bc()
    */
   public boolean isGL4bc();
 
   /**
    * Indicates whether this GL object conforms to the OpenGL ≥ 4.0 core profile.
    * The GL4 core profile includes the GL2ES2, and GL3 profile.
+   * @see GLContext#isGL4()
    */
   public boolean isGL4();
 
   /**
    * Indicates whether this GL object conforms to the OpenGL ≥ 3.1 compatibility profile.
    * The GL3 compatibility profile includes the GL2, GL2ES1, GL2ES2 and GL3 profile.
+   * @see GLContext#isGL3bc()
    */
   public boolean isGL3bc();
 
   /**
    * Indicates whether this GL object conforms to the OpenGL ≥ 3.1 core profile.
    * The GL3 core profile includes the GL2ES2 profile.
+   * @see GLContext#isGL3()
    */
   public boolean isGL3();
 
   /**
    * Indicates whether this GL object conforms to the OpenGL ≤ 3.0 profile.
    * The GL2 profile includes the GL2ES1 and GL2ES2 profile.
+   * @see GLContext#isGL2()
    */
   public boolean isGL2();
 
   /**
    * Indicates whether this GL object conforms to the OpenGL ES1 ≥ 1.0 profile.
+   * @see GLContext#isGLES1()
    */
   public boolean isGLES1();
 
@@ -127,6 +133,7 @@ public interface GLBase {
    * To query whether core ES2 functionality is provided, use {@link #isGLES2Compatible()}.
    * </p> 
    * @see #isGLES2Compatible()
+   * @see GLContext#isGLES2()
    */
   public boolean isGLES2();
 
@@ -137,44 +144,52 @@ public interface GLBase {
    * To query whether core ES3 functionality is provided, use {@link #isGLES3Compatible()}.
    * </p> 
    * @see #isGLES3Compatible()
+   * @see GLContext#isGLES3()
    */
   public boolean isGLES3();
   
   /**
    * Indicates whether this GL object conforms to one of the OpenGL ES profiles,
    * see {@link #isGLES1()} and {@link #isGLES2()}.
+   * @see GLContext#isGLES()
    */
   public boolean isGLES();
 
   /**
    * Indicates whether this GL object conforms to a GL2ES1 compatible profile.
+   * @see GLContext#isGL2ES1()
    */
   public boolean isGL2ES1();
 
   /**
    * Indicates whether this GL object conforms to a GL2ES2 compatible profile.
+   * @see GLContext#isGL2ES2()
    */
   public boolean isGL2ES2();
 
   /**
    * Indicates whether this GL object conforms to a GL3ES3 compatible profile.
+   * @see GLContext#isGL3ES3()
    */
   public boolean isGL3ES3();
 
   /**
    * Indicates whether this GL object conforms to a GL4ES3 compatible profile.
+   * @see GLContext#isGL4ES3()
    */
   public boolean isGL4ES3();
 
   /**
    * Indicates whether this GL object conforms to a GL2GL3 compatible profile.
+   * @see GLContext#isGL2GL3()
    */
   public boolean isGL2GL3();
 
   /**
    * Indicates whether this GL object is compatible with the core OpenGL ES2 functionality.
    * @return true if this context is an ES2 context or implements 
-   *         the extension <code>GL_ARB_ES2_compatibility</code>, otherwise false 
+   *         the extension <code>GL_ARB_ES2_compatibility</code>, otherwise false
+   * @see GLContext#isGLES2Compatible() 
    */
   public boolean isGLES2Compatible();
 
@@ -182,93 +197,117 @@ public interface GLBase {
    * Indicates whether this GL object is compatible with the core OpenGL ES3 functionality.
    * @return true if this context is an ES3 context or implements 
    *         the extension <code>GL_ARB_ES3_compatibility</code>, otherwise false 
+   * @see GLContext#isGLES3Compatible() 
    */
   public boolean isGLES3Compatible();
 
-  /** Indicates whether this GL object supports GLSL. */
+  /** 
+   * Indicates whether this GL object supports GLSL. 
+   * @see GLContext#hasGLSL() 
+   */
   public boolean hasGLSL();
 
   /**
+   * Returns the downstream GL instance in case this is a wrapping pipeline, otherwise <code>null</code>.
+   * <p>
+   * See {@link #getRootGL()} for retrieving the implementing root instance. 
+   * </p>
+   * @throws GLException if the downstream instance is not null and not a GL implementation
+   * @see #getRootGL()
+   */
+  public GL getDownstreamGL() throws GLException;
+  
+  /**
+   * Returns the implementing root instance, considering a wrapped pipelined hierarchy, see {@link #getDownstreamGL()}.
+   * <p>
+   * If this instance is not a wrapping pipeline, i.e. has no downstream instance,
+   * this instance is returned.
+   * </p>
+   * @throws GLException if the root instance is not a GL implementation
+   */
+  public GL getRootGL() throws GLException;
+  
+  /**
    * Casts this object to the GL interface.
-   * @throws GLException if this GLObject is not a GL implementation
+   * @throws GLException if this object is not a GL implementation
    */
   public GL getGL() throws GLException;
 
   /**
    * Casts this object to the GL4bc interface.
-   * @throws GLException if this GLObject is not a GL4bc implementation
+   * @throws GLException if this object is not a GL4bc implementation
    */
   public GL4bc getGL4bc() throws GLException;
 
   /**
    * Casts this object to the GL4 interface.
-   * @throws GLException if this GLObject is not a GL4 implementation
+   * @throws GLException if this object is not a GL4 implementation
    */
   public GL4 getGL4() throws GLException;
 
   /**
    * Casts this object to the GL3bc interface.
-   * @throws GLException if this GLObject is not a GL3bc implementation
+   * @throws GLException if this object is not a GL3bc implementation
    */
   public GL3bc getGL3bc() throws GLException;
 
   /**
    * Casts this object to the GL3 interface.
-   * @throws GLException if this GLObject is not a GL3 implementation
+   * @throws GLException if this object is not a GL3 implementation
    */
   public GL3 getGL3() throws GLException;
 
   /**
    * Casts this object to the GL2 interface.
-   * @throws GLException if this GLObject is not a GL2 implementation
+   * @throws GLException if this object is not a GL2 implementation
    */
   public GL2 getGL2() throws GLException;
 
   /**
    * Casts this object to the GLES1 interface.
-   * @throws GLException if this GLObject is not a GLES1 implementation
+   * @throws GLException if this object is not a GLES1 implementation
    */
   public GLES1 getGLES1() throws GLException;
 
   /**
    * Casts this object to the GLES2 interface.
-   * @throws GLException if this GLObject is not a GLES2 implementation
+   * @throws GLException if this object is not a GLES2 implementation
    */
   public GLES2 getGLES2() throws GLException;
 
   /**
    * Casts this object to the GLES3 interface.
-   * @throws GLException if this GLObject is not a GLES3 implementation
+   * @throws GLException if this object is not a GLES3 implementation
    */
   public GLES3 getGLES3() throws GLException;
 
   /**
    * Casts this object to the GL2ES1 interface.
-   * @throws GLException if this GLObject is not a GL2ES1 implementation
+   * @throws GLException if this object is not a GL2ES1 implementation
    */
   public GL2ES1 getGL2ES1() throws GLException;
 
   /**
    * Casts this object to the GL2ES2 interface.
-   * @throws GLException if this GLObject is not a GL2ES2 implementation
+   * @throws GLException if this object is not a GL2ES2 implementation
    */
   public GL2ES2 getGL2ES2() throws GLException;
 
   /**
    * Casts this object to the GL3ES3 interface.
-   * @throws GLException if this GLObject is not a GL3ES3 implementation
+   * @throws GLException if this object is not a GL3ES3 implementation
    */
   public GL3ES3 getGL3ES3() throws GLException;
 
   /**
    * Casts this object to the GL4ES3 interface.
-   * @throws GLException if this GLObject is not a GL3ES3 implementation
+   * @throws GLException if this object is not a GL3ES3 implementation
    */
   public GL4ES3 getGL4ES3() throws GLException;
 
   /**
    * Casts this object to the GL2GL3 interface.
-   * @throws GLException if this GLObject is not a GL2GL3 implementation
+   * @throws GLException if this object is not a GL2GL3 implementation
    */
   public GL2GL3 getGL2GL3() throws GLException;
 
diff --git a/src/jogl/classes/javax/media/opengl/GLContext.java b/src/jogl/classes/javax/media/opengl/GLContext.java
index b27db18af..9d383c371 100644
--- a/src/jogl/classes/javax/media/opengl/GLContext.java
+++ b/src/jogl/classes/javax/media/opengl/GLContext.java
@@ -504,6 +504,17 @@ public abstract class GLContext {
   public abstract void destroy();
 
   /**
+   * Returns the implementing root GL instance of this GLContext's GL object, 
+   * considering a wrapped pipelined hierarchy, see {@link GLBase#getDownstreamGL()}.
+   * @throws GLException if the root instance is not a GL implementation
+   * @see GLBase#getRootGL()
+   * @see GLBase#getDownstreamGL()
+   * @see #getGL()
+   * @see #setGL(GL)
+   */
+  public abstract GL getRootGL();
+  
+  /**
    * Returns the GL pipeline object for this GLContext.
    *
    * @return the aggregated GL instance, or null if this context was not yet made current.
@@ -915,40 +926,83 @@ public abstract class GLContext {
              isExtensionAvailable(GLExtensions.IMG_texture_format_BGRA8888) ;
   }
 
-  /** @see GLProfile#isGL4bc() */
+  /** 
+   * Indicates whether this GLContext is capable of GL4bc.  <p>Includes [ GL4bc ].</p>
+   * @see GLProfile#isGL4bc() 
+   */
   public final boolean isGL4bc() {
       return ctxVersion.getMajor() >= 4 && 0 != (ctxOptions & CTX_IS_ARB_CREATED)
                                         && 0 != (ctxOptions & CTX_PROFILE_COMPAT);
   }
 
-  /** @see GLProfile#isGL4() */
+  /** 
+   * Indicates whether this GLContext is capable of GL4.    <p>Includes [ GL4bc, GL4 ].</p>
+   * @see GLProfile#isGL4() 
+   */
   public final boolean isGL4() {
       return ctxVersion.getMajor() >= 4 && 0 != (ctxOptions & CTX_IS_ARB_CREATED)
                                         && 0 != (ctxOptions & (CTX_PROFILE_COMPAT|CTX_PROFILE_CORE));
   }
 
-  /** Indicates whether this profile is capable of GL4 (core only). <p>Includes [ GL4 ].</p> */
+  /** 
+   * Indicates whether this GLContext is capable of GL4 (core only). <p>Includes [ GL4 ].</p> 
+   */
   public final boolean isGL4core() {
       return ctxVersion.getMajor() >= 4 && 0 != (ctxOptions & CTX_IS_ARB_CREATED)
                                         && 0 != (ctxOptions & CTX_PROFILE_CORE);
   }
   
-  /** @see GLProfile#isGL3bc() */
+  /** 
+   * Indicates whether this GLContext is capable of GL3bc.  <p>Includes [ GL4bc, GL3bc ].</p>
+   * @see GLProfile#isGL3bc() 
+   */
   public final boolean isGL3bc() {
       return 0 != (ctxOptions & CTX_IS_ARB_CREATED) &&
              0 != (ctxOptions & CTX_PROFILE_COMPAT) &&
              ctxVersion.compareTo(Version310) >= 0 ;
   }
 
-  /** @see GLProfile#isGL3() */
+  /** 
+   * Indicates whether this GLContext is capable of GL3.    <p>Includes [ GL4bc, GL4, GL3bc, GL3 ].</p>
+   * @see GLProfile#isGL3() 
+   */
   public final boolean isGL3() {
       return 0 != (ctxOptions & CTX_IS_ARB_CREATED) &&
              0 != (ctxOptions & (CTX_PROFILE_COMPAT|CTX_PROFILE_CORE)) &&
              ctxVersion.compareTo(Version310) >= 0 ;
   }
   
-  /** Indicates whether this profile is capable of GL3 (core only). GL3 starts w/ OpenGL 3.1 <p>Includes [ GL4, GL3, GLES3 ].</p> */
+  /** 
+   * Indicates whether this GLContext is capable of GL3 (core only). GL3 starts w/ OpenGL 3.1 <p>Includes [ GL4, GL3 ].</p>
+   */
   public final boolean isGL3core() {
+      return 0 != ( ctxOptions & CTX_IS_ARB_CREATED ) &&
+             0 != ( ctxOptions & CTX_PROFILE_CORE ) &&
+             ctxVersion.compareTo(Version310) >= 0;
+  }
+  
+  /** 
+   * Indicates whether this GLContext's native profile does not implement a default <i>vertex array object</i> (VAO), 
+   * starting w/ OpenGL 3.1 core and GLES3.
+   * <p>Includes [ GL4, GL3, GLES3 ].</p>
+   * <pre>
+     Due to GL 3.1 core spec: E.1. DEPRECATED AND REMOVED FEATURES (p 296),
+            GL 3.2 core spec: E.2. DEPRECATED AND REMOVED FEATURES (p 331)
+     there is no more default VAO buffer 0 bound, hence generating and binding one
+     to avoid INVALID_OPERATION at VertexAttribPointer. 
+     More clear is GL 4.3 core spec: 10.4 (p 307).
+   * </pre>
+   * <pre>
+     GLES3 is included, since upcoming ES releases &gt; 3.0 may behave the same:
+            GL ES 3.0 spec F.1. Legacy Features (p 322).
+   * </pre>
+   * <p>
+   * If no default VAO is implemented in the native OpenGL profile,
+   * an own default VAO is being used, see {@link #getDefaultVAO()}.
+   * </p>
+   * @see #getDefaultVAO()
+   */
+  public final boolean hasNoDefaultVAO() {
       return ( 0 != ( ctxOptions & CTX_PROFILE_ES ) && ctxVersion.getMajor() >= 3 ) ||
              ( 0 != ( ctxOptions & CTX_IS_ARB_CREATED ) &&
                0 != ( ctxOptions & CTX_PROFILE_CORE ) &&
@@ -956,52 +1010,87 @@ public abstract class GLContext {
              ) ;
   }
   
-  /** @see GLProfile#isGL2() */
+  /**
+   * If this GLContext does not implement a default VAO, see {@link #hasNoDefaultVAO()},
+   * an <i>own default VAO</i> will be created and bound at context creation.
+   * <p>
+   * If this GLContext does implement a default VAO, i.e. {@link #hasNoDefaultVAO()}
+   * returns <code>false</code>, this method returns <code>0</code>.
+   * </p> 
+   * <p>
+   * Otherwise this method returns the VAO object name
+   * representing this GLContext's <i>own default VAO</i>.  
+   * </p> 
+   * @see #hasNoDefaultVAO()
+   */
+  public abstract int getDefaultVAO();
+
+  /** 
+   * @see GLProfile#isGL2() 
+   */
   public final boolean isGL2() {
       return 0 != ( ctxOptions & CTX_PROFILE_COMPAT ) && ctxVersion.getMajor()>=1 ;
   }
 
-  /** @see GLProfile#isGL2GL3() */  
+  /** 
+   * @see GLProfile#isGL2GL3() 
+   */  
   public final boolean isGL2GL3() {
       return isGL2() || isGL3();
   }
 
-  /** @see GLProfile#isGLES1() */
+  /** 
+   * @see GLProfile#isGLES1() 
+   */
   public final boolean isGLES1() {
       return 0 != ( ctxOptions & CTX_PROFILE_ES ) && ctxVersion.getMajor() == 1 ;
   }
 
-  /** @see GLProfile#isGLES2() */
+  /** 
+   * @see GLProfile#isGLES2() 
+   */
   public final boolean isGLES2() {
       return 0 != ( ctxOptions & CTX_PROFILE_ES ) && ctxVersion.getMajor() >= 2 ;
   }
 
-  /** @see GLProfile#isGLES3() */
+  /** 
+   * @see GLProfile#isGLES3() 
+   */
   public final boolean isGLES3() {
       return 0 != ( ctxOptions & CTX_PROFILE_ES ) && ctxVersion.getMajor() >= 3 ;
   }
 
-  /** @see GLProfile#isGLES() */
+  /** 
+   * @see GLProfile#isGLES() 
+   */
   public final boolean isGLES() {
       return 0 != ( CTX_PROFILE_ES & ctxOptions ) ;
   }
 
-  /** @see GLProfile#isGL2ES1() */
+  /** 
+   * @see GLProfile#isGL2ES1() 
+   */
   public final boolean isGL2ES1() {
       return isGLES1() || isGL2();
   }
 
-  /** @see GLProfile#isGL2ES2() */
+  /** 
+   * @see GLProfile#isGL2ES2() 
+   */
   public final boolean isGL2ES2() {
       return isGLES2() || isGL2GL3();
   }
 
-  /** @see GLProfile#isGL3ES3() */
+  /** 
+   * @see GLProfile#isGL3ES3() 
+   */
   public final boolean isGL3ES3() {
       return isGL4ES3() || isGL3();
   }
 
-  /** @see GLProfile#isGL4ES3() */
+  /** 
+   * @see GLProfile#isGL4ES3() 
+   */
   public final boolean isGL4ES3() {
       return isGL4() || isGLES3() ;
   }