/** Clears the playback surface to black. */
private void clearSurface(Surface surface) {
// We need to do this with OpenGL ES (*not* Canvas -- the "software render" bits
// are sticky). We can't stay connected to the Surface after we're done because
// that'd prevent the video encoder from attaching.
//
// If the Surface is resized to be larger, the new portions will be black, so
// clearing to something other than black may look weird unless we do the clear
// post-resize.
EglCore eglCore = new EglCore();
WindowSurface win = new WindowSurface(eglCore, surface, false);
win.makeCurrent();
GLES20.glClearColor(0, 0, 0, 0);
GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT);
win.swapBuffers();
win.release();
eglCore.release();
}
