Tick mark wrong in texture sample

[PrincessGod]

In this sample,
use this code in render part

       // Compute the projection matrix
132    var projectionMatrix =
133        m4.orthographic(0, gl.canvas.clientWidth, gl.canvas.clientHeight, 0, -1, 1);

and the m4.orthographic() set 0 -> gl.canvas.clientHeight form top to bottom

...
    function orthographic(left, right, bottom, top, near, far, dst) {
...

but set 0 -> positive (-1, 4) from bottom to top for tick marks ,
maybe it have to be (4, -1) from bottom to top.
I founded this when check both direction to CLAMP_TO_EDGE.

[greggman]

Doh! Fixed

5815d73