Positioning Screen Space UI element in center of a grid square?

Questions & Answers
1

I want to be able to click/touch anywhere in a grid square and snap a screen space UI element (popup menu) to the center of that square.

I have an empty gameobject that has a grid with each box equal to one world unit (see screenshot bellow). The gameobject has a transform, a box collider, and script on it. I can snap to a local position in the grid with the code below, but I can’t seem to figure out how to convert a Local point to Screen Space point. How can I find the coordinates to snap a Screen Space UI element to the center of a grid square that is in local world units?

Thanks for the help

< TL;DR >

This code works for locally positioned gameobject, how do I get from here to screen space UI element snapped to the center of a grid square?

// Snaps a local positioned gameobject to the center of a grid square.
// Each grid square is one world unit.
// midPoint = 0.5f;
transform.position = new Vector3(Mathf.FloorToInt(localPoint.x) + midPoint, Mathf.FloorToInt(localPoint.y) + midPoint, localPoint.z);

91784-screenshot.jpg
91784-screenshot.jpg797×1278 79.4 KB

Screenshot of the prototype with grid.

2

I figured it out something that works.

_localPoint =  new Vector3(Mathf.FloorToInt(localPoint.x) + midPoint, Mathf.FloorToInt(localPoint.y) + midPoint, localPoint.z);

_menu.transform.position = ConvertLocalToScreenPoint(_localPoint);

// ...

private Vector3 ConvertLocalToScreenPoint(Vector3 localPoint)
{
    return RectTransformUtility.WorldToScreenPoint(Camera.main, transform.TransformPoint(localPoint));
}