I tried to display a model with many vertices. However, it seems that it is displayed only halfway. [RedGL + Kaendoki.glb result:](http://jsdo.it/cx20/4MRs)  I think that it is probably caused by not supporting the `OES_element_index_uint` extension. [three.js + Kaendoki.glb result:](http://jsdo.it/cx20/gtTA) 