question: glass render?

[flash0tt]

Hi! how to make a glass block like vanilla? model is the same with vanilla.
{
"type": "block:simple",
"entries": [{
"id": "glass_n_1",
"material": "glass",
"creativeTab": "it_project",
"renderLayer": "cutout",
"opacity": 1,
"isOpaqueCube": false,
"isFullCube": false
}]
}
screen shot:
https://i.loli.net/2018/09/15/5b9cc7648c586.png