// Copyright (c) Microsoft Corporation. All rights reserved. // Licensed under the MIT License. See LICENSE in the project root for license information. using UnityEngine; namespace HoloToolkit.Unity { /// <summary> /// Causes a Hologram to maintain a fixed angular size, which is to say it /// occupies the same pixels in the view regardless of its distance from /// the camera. /// </summary> public class FixedAngularSize : MonoBehaviour { /// <summary> /// Offsets the scale ratio so that text does not scale down too much. (Set to zero for linear scaling) /// </summary> [Tooltip("Offsets the scale ratio so that text does not scale down too much. (Set to zero for linear scaling)")] [Range(0.0f, 1.0f)] [SerializeField] private float sizeRatio = 0.0f; public float SizeRatio { get { return sizeRatio; } set { // Set the value of sizeRatio, while maintaining the supported range. if (value < 0.0f) { sizeRatio = 0.0f; } else if (value > 1.0f) { sizeRatio = 1.0f; } else { sizeRatio = value; } } } /// <summary> /// The ratio between the transform's local scale and its starting distance from the camera. /// </summary> private Vector3 startingScale; /// <summary> /// The starting distance from the camera. /// </summary> private float startingDistance; private void Start() { // Calculate the XYZ ratios for the transform's localScale over its // initial distance from the camera. startingDistance = Vector3.Distance(CameraCache.Main.transform.position, transform.position); startingScale = transform.localScale; SetSizeRatio(SizeRatio); } /// <summary> /// Manually update the OverrideSizeRatio during runtime or through UnityEvents in the editor /// </summary> /// <param name="ratio"> 0 - 1 : Use 0 for linear scaling</param> public void SetSizeRatio(float ratio) { if (ratio == 0) { if (startingDistance > 0.0f) { // set to a linear scale ratio SizeRatio = 1 / startingDistance; } else { // If the transform and the camera are both in the same // position (that is, the distance between them is zero), // disable this Behaviour so we don't get a DivideByZero // error later on. enabled = false; #if UNITY_EDITOR Debug.LogWarning("The object and the camera are in the same position at Start(). The attached FixedAngularSize Behaviour is now disabled."); #endif // UNITY_EDITOR } } else { SizeRatio = ratio; } } /// <summary> /// LateUpdate is used to ensure that the scaling occurs after any other processing (ex: cursor placement). /// </summary> private void LateUpdate() { float distanceToHologram = Vector3.Distance(CameraCache.Main.transform.position, transform.position); // create an offset ratio based on the starting position. This value creates a new angle that pivots // on the starting position that is more or less drastic than the normal scale ratio. float curvedRatio = 1 - startingDistance * SizeRatio; transform.localScale = startingScale * (distanceToHologram * SizeRatio + curvedRatio); } } }