How can i store or read a animation clip data in runtime? - unity3d

Question

I'm working on a small program that can modify the animation at run time(Such as when you run faster the animation not only play faster but also with larger movement). So i need to get the existing animation, change its value, then send it back.
I found it is interesting that i can set a new curve to the animation, but i can't get access to what i already have. So I either write a file to store my animation curve (as text file for example), or i find someway to read the animation on start up.
I tried to use
AnimationUtility.GetCurveBindings(AnimationCurve);
It worked in my testing, but in some page it says this is a "Editor code", that if i build the project into a standalone program it will not work anymore. Is that true? If so, is there any way to get the curve at run time?
Thanks to the clearify from Benjamin Zach and suggestion from TehMightyPotato
I'd like to keep the idea about modifying the animation at runtime. Because it could adapt to more situations imo.
My idea for now is to write a piece of editor code that can read from the curve in Editor and output all necesseary information about the curve (keyframes) into a text file. Then read that file at runtime and create new curve to overwrite the existing one. I will leave this question open for a few days and check it to see if anyone has a better idea about it.

Answer 1

As said already AnimationUtility belongs to the UnityEditor namespace. This entire namespace is completely stripped of in a build and nothing in it will be available in the final app but only within the Unity Editor.
Store AnimationCurves to file
In order to store all needed information to a file you could have a script for once serializing your specific animation curve(s) in the editor before building using e.g. BinaryFormatter.Serialize. Then later on runtime you can use BinaryFormatter.Deserialize for returning the info list again.
If you wanted it more editable you could as well use e.g. JSON or XML of course
UPDATE: In general Stop using BinaryFormatter!
In the newest Unity versions the Newtonsoft Json.NET package comes already preinstalled so simply rather use JSON
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using Unity.Plastic.Newtonsoft.Json;
using UnityEditor;
using UnityEngine;
using Object = UnityEngine.Object;
public class AnimationCurveManager : MonoBehaviour
{
[Serializable]
public sealed class ClipInfo
{
public int ClipInstanceID;
public List<CurveInfo> CurveInfos = new List<CurveInfo>();
// default constructor is sometimes required for (de)serialization
public ClipInfo() { }
public ClipInfo(Object clip, List<CurveInfo> curveInfos)
{
ClipInstanceID = clip.GetInstanceID();
CurveInfos = curveInfos;
}
}
[Serializable]
public sealed class CurveInfo
{
public string PathKey;
public List<KeyFrameInfo> Keys = new List<KeyFrameInfo>();
public WrapMode PreWrapMode;
public WrapMode PostWrapMode;
// default constructor is sometimes required for (de)serialization
public CurveInfo() { }
public CurveInfo(string pathKey, AnimationCurve curve)
{
PathKey = pathKey;
foreach (var keyframe in curve.keys)
{
Keys.Add(new KeyFrameInfo(keyframe));
}
PreWrapMode = curve.preWrapMode;
PostWrapMode = curve.postWrapMode;
}
}
[Serializable]
public sealed class KeyFrameInfo
{
public float Value;
public float InTangent;
public float InWeight;
public float OutTangent;
public float OutWeight;
public float Time;
public WeightedMode WeightedMode;
// default constructor is sometimes required for (de)serialization
public KeyFrameInfo() { }
public KeyFrameInfo(Keyframe keyframe)
{
Value = keyframe.value;
InTangent = keyframe.inTangent;
InWeight = keyframe.inWeight;
OutTangent = keyframe.outTangent;
OutWeight = keyframe.outWeight;
Time = keyframe.time;
WeightedMode = keyframe.weightedMode;
}
}
// I know ... singleton .. but what choices do we have? ;)
private static AnimationCurveManager _instance;
public static AnimationCurveManager Instance
{
get
{
// lazy initialization/instantiation
if (_instance) return _instance;
_instance = FindObjectOfType<AnimationCurveManager>();
if (_instance) return _instance;
_instance = new GameObject("AnimationCurveManager").AddComponent<AnimationCurveManager>();
return _instance;
}
}
// Clips to manage e.g. reference these via the Inspector
public List<AnimationClip> clips = new List<AnimationClip>();
// every animation curve belongs to a specific clip and
// a specific property of a specific component on a specific object
// for making this easier lets simply use a combined string as key
private string CurveKey(string pathToObject, Type type, string propertyName)
{
return $"{pathToObject}:{type.FullName}:{propertyName}";
}
public List<ClipInfo> ClipCurves = new List<ClipInfo>();
private string filePath = Path.Combine(Application.streamingAssetsPath, "AnimationCurves.dat");
private void Awake()
{
if (_instance && _instance != this)
{
Debug.LogWarning("Multiple Instances of AnimationCurveManager! Will ignore this one!", this);
return;
}
_instance = this;
DontDestroyOnLoad(gameObject);
// load infos on runtime
LoadClipCurves();
}
#if UNITY_EDITOR
// Call this from the ContextMenu (or later via editor script)
[ContextMenu("Save Animation Curves")]
private void SaveAnimationCurves()
{
ClipCurves.Clear();
foreach (var clip in clips)
{
var curveInfos = new List<CurveInfo>();
ClipCurves.Add(new ClipInfo(clip, curveInfos));
foreach (var binding in AnimationUtility.GetCurveBindings(clip))
{
var key = CurveKey(binding.path, binding.type, binding.propertyName);
var curve = AnimationUtility.GetEditorCurve(clip, binding);
curveInfos.Add(new CurveInfo(key, curve));
}
}
// create the StreamingAssets folder if it does not exist
try
{
if (!Directory.Exists(Application.streamingAssetsPath))
{
Directory.CreateDirectory(Application.streamingAssetsPath);
}
}
catch (IOException ex)
{
Debug.LogError(ex.Message);
}
// create a new file e.g. AnimationCurves.dat in the StreamingAssets folder
var json = JsonConvert.SerializeObject(ClipCurves);
File.WriteAllText(filePath, json);
AssetDatabase.Refresh();
}
#endif
private void LoadClipCurves()
{
if (!File.Exists(filePath))
{
Debug.LogErrorFormat(this, "File \"{0}\" not found!", filePath);
return;
}
var fileStream = new FileStream(filePath, FileMode.Open);
var json = File.ReadAllText(filePath);
ClipCurves = JsonConvert.DeserializeObject<List<ClipInfo>>(json);
}
// now for getting a specific clip's curves
public AnimationCurve GetCurve(AnimationClip clip, string pathToObject, Type type, string propertyName)
{
// either not loaded yet or error -> try again
if (ClipCurves == null || ClipCurves.Count == 0) LoadClipCurves();
// still null? -> error
if (ClipCurves == null || ClipCurves.Count == 0)
{
Debug.LogError("Apparantly no clipCurves loaded!");
return null;
}
var clipInfo = ClipCurves.FirstOrDefault(ci => ci.ClipInstanceID == clip.GetInstanceID());
// does this clip exist in the dictionary?
if (clipInfo == null)
{
Debug.LogErrorFormat(this, "The clip \"{0}\" was not found in clipCurves!", clip.name);
return null;
}
var key = CurveKey(pathToObject, type, propertyName);
var curveInfo = clipInfo.CurveInfos.FirstOrDefault(c => string.Equals(c.PathKey, key));
// does the curve key exist for the clip?
if (curveInfo == null)
{
Debug.LogErrorFormat(this, "The key \"{0}\" was not found for clip \"{1}\"", key, clip.name);
return null;
}
var keyframes = new Keyframe[curveInfo.Keys.Count];
for (var i = 0; i < curveInfo.Keys.Count; i++)
{
var keyframe = curveInfo.Keys[i];
keyframes[i] = new Keyframe(keyframe.Time, keyframe.Value, keyframe.InTangent, keyframe.OutTangent, keyframe.InWeight, keyframe.OutWeight)
{
weightedMode = keyframe.WeightedMode
};
}
var curve = new AnimationCurve(keyframes)
{
postWrapMode = curveInfo.PostWrapMode,
preWrapMode = curveInfo.PreWrapMode
};
// otherwise finally return the AnimationCurve
return curve;
}
}
Then you can do something like e.e.
AnimationCurve originalCurve = AnimationCurvesManager.Instance.GetCurve(
clip,
"some/relative/GameObject",
typeof<SomeComponnet>,
"somePropertyName"
);
the second parameter pathToObject is an empty string if the property/component is attached to the root object itself. Otherwise it is given in the hierachy path as usual for Unity like e.g. "ChildName/FurtherChildName".
Now you can change the values and assign a new curve on runtime.
Assigning new curve on runtime
On runtime you can use animator.runtimeanimatorController in order to retrieve a RuntimeAnimatorController reference.
It has a property animationClips which returns all AnimationClips assigned to this controller.
You could then use e.g. Linq FirstOrDefault in order to find a specific AnimationClip by name and finally use AnimationClip.SetCurve to assign a new animation curve to a certain component and property.
E.g. something like
// you need those of course
string clipName;
AnimationCurve originalCurve = AnimationCurvesManager.Instance.GetCurve(
clip,
"some/relative/GameObject",
typeof<SomeComponnet>,
"somePropertyName"
);
// TODO
AnimationCurve newCurve = SomeMagic(originalCurve);
// get the animator reference
var animator = animatorObject.GetComponent<Animator>();
// get the runtime Animation controller
var controller = animator.runtimeAnimatorController;
// get all clips
var clips = controller.animationClips;
// find the specific clip by name
// alternatively you could also get this as before using a field and
// reference the according script via the Inspector
var someClip = clips.FirstOrDefault(clip => string.Equals(clipName, clip.name));
// was found?
if(!someClip)
{
Debug.LogWarningFormat(this, "There is no clip called {0}!", clipName);
return;
}
// assign a new curve
someClip.SetCurve("relative/path/to/some/GameObject", typeof(SomeComponnet), "somePropertyName", newCurve);
Note: Typed on smartphone so no warranty! But I hope the idea gets clear...
Also checkout the example in AnimationClip.SetCurve → You might want to use the Animation component instead of an Animator in your specific use case.