How to use RenderTexture to render the whole scene with multiple Cameras in LUA?

Recently in my game, I want to render the whole scene to the render texture and blur it as the background.

The following code does not work, I get a blank image. “self” here is the instance of Scene in LUA

rt:begin()
self:visit()
rt:endToLua()

I have trid to use “self:render(cc.Director:getInstance():getRenderer())” to replace “self:visit()”. But “getRenderer()” is not exported to LUA. I also have tried to use “cc.Director:getInstance():drawScene()”, it still not work!

If I call “visit” of the children of the Scene, everything seems correct but the Camera is not specified.

So, how to render the whole scene to the RenderTexture with more than one Camera? Thanks.

In current mechanism,we can’t render the whole scene to the RenderTexture with more than one camera, and this work is under way. And we don’t do the render things in the Lua as far as possible.

cocos2dx ccUtils captureScreen works fine with 3D and, I assume, anything.

Need to use Frame Buffer Object to capture multiple cameras.