Rotating GUI Texture By Angle

Questions & Answers
1

So I used Ben Pitt’s code from this post: how to rotate GUI Textures - Questions & Answers - Unity Discussions to get the rotation part working. Now what I need is for the texture to always point toward a game object in the scene, I’m not sure how to do this, I’ve tried a few things that didn’t work. Any ideas?

2

Hopefully this works for you, unfortunately I can only really read C# and can’t write it so easily so I’ve written this in unityscript, but maybe you can convert the additions I’ve made, or possibly unityscript is fine for you…

var texture : Texture2D = null;
var angle : float = 0;
var size : Vector2 = new Vector2(128, 128);
var pos : Vector2 = new Vector2(0, 0);
var rect : Rect;
var pivot : Vector2;

var targetObj : GameObject;
var screenPos : Vector2;
var offset : Vector2;
var Rads : float = 0;

function Start() {
	UpdateSettings();
}

function Update() {
	screenPos = Camera.main.WorldToScreenPoint(targetObj.transform.position);
	screenPos.y = Screen.height-screenPos.y;
	offset = screenPos - pos;
	Rads = Mathf.Atan2(offset.y, offset.x)-(Mathf.PI/2);
	RadDegConvert(Rads);
}

function UpdateSettings() {
	pos = new Vector2(transform.localPosition.x, transform.localPosition.y);
	rect = new Rect(pos.x - size.x * 0.5f, pos.y - size.y * 0.5f, size.x, size.y);
	pivot = new Vector2(rect.xMin + rect.width * 0.5f, rect.yMin + rect.height * 0.5f);
}

function OnGUI() {
	if (Application.isEditor) { UpdateSettings(); }
	var matrixBackup : Matrix4x4 = GUI.matrix;
	GUIUtility.RotateAroundPivot(angle, pivot);
	GUI.DrawTexture(rect, texture);
	GUI.matrix = matrixBackup;
}

function RadDegConvert(radians) {
	angle = radians*360/(Mathf.PI*2);
}

hope that works for you,

Scribe

3

Your code worked perfectly except for one part… it was inverted. To fix that I added the lines pos.y = Screen.height - pos.y; and `screenPos.y = Screen.height - screenPos.y; before you calculate the offset. This is something I found out about very recently. Thanks!