want help with code, to draw a fullscreen quad

[kyoobey]

here is my full code: https://gist.github.com/tshrpl/01999d1244a92acb4812abede2a3ff3d

the result i get:

expected result: a fullscreen quad

[kvark]

Your example is fairly large. I would recommend just taking hello-triangle, and growing it into what you need.

[kyoobey]

found the problem
its line 509 in main.rs https://gist.github.com/tshrpl/01999d1244a92acb4812abede2a3ff3d#file-main-rs-L509
centroid should be the average of _vertex_0 and _vertex_2 or _vertex_1 and _vertex_3 not _vertex_0 and _vertex_3