store a reference to a float in a variable? (similar to what the "ref" keyword does)

Hello everyone,

is it possible to store a referece of a float?
What i tried (using the “ref” keyword):

List<FloatInfo> backups = new List<FloatInfo>();
public void BackupInt(ref float referenceToFloat, float value) {
     backups.Add(new FloatInfo(referenceToFloat, value);
public class FloatInfo {
    public float reference; // Since the "ref" keyword is only available for function parameters i can't do "public ref float referece";
    public float value;
    public FloatInfo(ref flaot reference, float backupValue) {
         // unfortunately this copies the variable instead of using the reference. Therefore the reference is gone :(
         this.reference = reference; 
         this.value = backupValue;

I need the reference to know what variable i am dealing with. When i need to call a backup i just want to set the int reference equal the backupValue. By that i want to achieve a Undo system.

Hopefully you understand what i want to achieve (It’s kind of tricky to explain). Do you have an idea to solve this?

(wrapping the int in a class is not the solution. The reference realy needs to refer to the “origin” float. I want to undo transform.position.x values by that)

While there is the nullable float option ( float? ), it does not actually store a reference.
Though the ref keyword does exactly what you want, it can only be applied to function parameters, not member variables.

Alas, I don’t think this is going to be possible, without a wrapper class. (Hopefully, someone will post otherwise.)

That being said, don’t forget you have the ability to define IMPLICIT cast to/from float functions, that should allow you to use your wrapper class everywhere you can use a normal float. But even then, if want to keep a reference, rather than a value, you would need to declare the variables you STORE as that wrapper-class, rather than a float. (This obviously excludes the transform.position.x you wanted to use: in this case, you would need to keep the reference to the transform class itself, and somehow, know which member of the transform to use.)

I think Unite Austin 2017 conference about game architecture seems to answer this, and spoiler, with ScriptableObject.

[CreateAssetMenu(fileName ="FloatVariable", menuName = "Architecture/Float Variable")]
public class FloatVariable : ScriptableObject {
    public float value;

public class FloatReference {
    public bool useConstant = true;
    public float constant;
    public FloatVariable variable;

    public float Value => (useConstant)
             ? m_constant : m_variable.value;