How can I draw 2D triangles in Unity 5?

I'm trying to draw 2D triangles using this or this (scripts) but unsuccessfully (I don't see any triangles). I have only camera, canvas and panel in it, also I've tried to apply it on empty canvas's child object, how must I apply these scripts? I've tried different variations. And is it a good way to draw triangles or is there something better? Also I've read somewhere here that GL Class doesn't work on iOS and/or Mac, is it true?