static int PingPong=0;
	PingPong= ( PingPong+ 1) % 4;

	start_fbo(accum[PingPong].fbo,XRES,YRES);
	sky_do(sceneTime);
	end_fbo();

	char temp[5]={0};
	int blurtex[4];
	for (int i=0;i<4;i++)
	{
		ZeroMemory(temp,5);
		sprintf(temp,"tex%d",i+1,4);
		blurtex[i]=oglGetUniformLocation(blur_shaderobj, temp);
	}
	oglUseProgram(  blur_shaderobj );
	for (int i=0;i<4;i++)
	{
		oglUniform1i(blurtex[i], i);
		oglActiveTextureARB(GL_TEXTURE0_ARB + i);
		glBindTexture(GL_TEXTURE_2D,accum[((PingPong + i) % 4)].texture);
	}
	oglActiveTextureARB(GL_TEXTURE0_ARB + 0);
	draw_fbtexture(accum[PingPong].texture,XRES, YRES);
	oglUseProgram( NULL );
	glBindTexture(GL_TEXTURE_2D,0);