docs: public void start() {
                  // Log.d("EglHelper" + instanceId, "start()");
                  if (mEgl == null) {
                          // Log.d("EglHelper" + instanceId, "getting new EGL");
                          /*
                           * Get an EGL instance
                           */
                          mEgl = (EGL10) EGLContext.getEGL();
                  } else {
                          // Log.d("EglHelper" + instanceId, "reusing EGL");
                  }
  
                  if (mEglDisplay == null) {
                          // Log.d("EglHelper" + instanceId, "getting new display");
                          /*
                           * Get to the default display.
                           */
                          mEglDisplay = mEgl.eglGetDisplay(EGL10.EGL_DEFAULT_DISPLAY);
                  } else {
                          // Log.d("EglHelper" + instanceId, "reusing display");
                  }
  
                  if (mEglConfig == null) {
                          // Log.d("EglHelper" + instanceId, "getting new config");
                          /*
                           * We can now initialize EGL for that display
                           */
                          int[] version = new int[2];
                          mEgl.eglInitialize(mEglDisplay, version);
                          mEglConfig = mEGLConfigChooser.chooseConfig(mEgl, mEglDisplay);
                  } else {
                          // Log.d("EglHelper" + instanceId, "reusing config");
                  }
  
                  if (mEglContext == null) {
                          // Log.d("EglHelper" + instanceId, "creating new context");
                          /*
                           * Create an OpenGL ES context. This must be done only once, an OpenGL context is a somewhat heavy object.
                           */
                          mEglContext = mEGLContextFactory.createContext(mEgl, mEglDisplay, mEglConfig);
                          if (mEglContext == null || mEglContext == EGL10.EGL_NO_CONTEXT) {
                                  throw new RuntimeException("createContext failed");
                          }
                  } else {
                          // Log.d("EglHelper" + instanceId, "reusing context");
                  }
  
                  mEglSurface = null;
          }