question: public void initGL ( ) { mEglCore = new EglCore ( null , EglCore . FLAG_RECORDABLE | EglCore . FLAG_TRY_GLES3 ) ; mWindowSurface = new WindowSurface ( mEglCore , mSurfaceTexture ) ; mWindowSurface . makeCurrent ( ) ; mRecordSurface = new WindowSurface ( mEglCore , mMediaRecorder . getSurface ( ) , false ) ; initGLComponents ( ) ; }
target:  Initialize all necessary components for GLES rendering, creating window surfaces for drawing the preview as well as the surface that will be used by MediaRecorder for recording