JOGL: Proper handling of Read Drawable Support (if not supported), add query.

Read Drawable feature reflects the make context current API
having a seperate read drawable next to the write drawable (default).
  glXMakeContextCurrent(write, read, ..)

On X11 a ready drawable is only supported for GLX >= 1.3,
on Windows only if extension WGL_ARB_make_current_read is available,
on EGL it's always supported, on OSX not at all.

API cleanup GLContext:
  changes: setGLDrawableRead(GLDrawable) ->  setGLReadDrawable(GLDrawable)
  new:     isGLReadDrawableAvailable()
  new:     getGLExtensionsString();

Access qualifier cleanup.

GLContextImpl: GLVersionNumber moved out.

1 files changed, 7 insertions, 8 deletions

diff --git a/src/jogl/classes/com/jogamp/opengl/impl/egl/EGLContext.java b/src/jogl/classes/com/jogamp/opengl/impl/egl/EGLContext.java
index d95a9e3ff..246814537 100644
--- a/src/jogl/classes/com/jogamp/opengl/impl/egl/EGLContext.java
+++ b/src/jogl/classes/com/jogamp/opengl/impl/egl/EGLContext.java
@@ -50,14 +50,9 @@ public abstract class EGLContext extends GLContextImpl {
     // EGL extension functions.
     private EGLExtProcAddressTable eglExtProcAddressTable;
 
-    public EGLContext(GLDrawableImpl drawable, GLDrawableImpl drawableRead,
-                      GLContext shareWith) {
-        super(drawable, drawableRead, shareWith);
-    }
-
-    public EGLContext(GLDrawableImpl drawable,
-                      GLContext shareWith) {
-        this(drawable, null, shareWith);
+    EGLContext(GLDrawableImpl drawable,
+               GLContext shareWith) {
+        super(drawable, shareWith);
     }
 
     public Object getPlatformGLExtensions() {
@@ -83,6 +78,10 @@ public abstract class EGLContext extends GLContextImpl {
 
     protected Map/*<String, String>*/ getExtensionNameMap() { return null; }
 
+    public final boolean isGLReadDrawableAvailable() {
+        return true;
+    }
+
     protected void makeCurrentImpl(boolean newCreated) throws GLException {
         if(EGL.EGL_NO_DISPLAY==((EGLDrawable)drawable).getDisplay() ) {
             throw new GLException("drawable not properly initialized, NO DISPLAY: "+drawable);