There are two screen in our board. One is hdmi(1280x1024P-60 32bpp), another is lvds(1280x1024P-60 32bpp). When we try to render to one of the screen, it's smooth(export FB_MULTI_BUFFER=2). Now we need to render different graphics to two screen at the same time, but it's not smooth.
We create two process, and use 'eglNativeDisplayType = fbGetDisplayByIndex(x);' to render to /dev/fb0 and /dev/fb2.