[4.6 UI] Image fading - How to?

Questions & Answers
1

I want to make the FadePanel image to fade from 0 to 128, but its not really working :confused:

    using UnityEngine;
    using System.Collections;
    using UnityEngine.UI;
    
    public class PanelTransition : MonoBehaviour {
    	public Image FadePanel;

    	void Update ()
        {
    	   FadePanel.color.a = Mathf.Lerp(0,128,Time.time);
        }
    }
3

So, the answer above links to a solution from 2012. The author wants to know how you do it in the new 4.6 GUI library, which is only recently available. Take a look at UI.Graphic.CrossFadeAlpha found here.

Say you have a UI.Text object named text, and you want it to fade out over the next half second:

text.CrossFadeAlpha(0, .5f, false);

I hope this helps someone else. Sorry, I donā€™t understand what the false (ignore timestamp) does. The docs page for it is missing.

2

Found an answer Here

Basically, stay away from Time.time. that value is equal to the number of seconds that passed since you started the program.

Thereā€™s 2 options available to achieve what you want. either you use an incrementing value (that goes from 0 to 1 over time) instead of Time.time. Something like :

float timer = 0;
void Update()
{
    timer += Time.deltaTime;
    FadePanel.color.a = Mathf.Lerp(0,128,timer);
}

Or, you use a different ā€œfrom valueā€ every frameā€¦ your ā€œcurrent valueā€ actually. like so :

void Update()
{
    FadePanel.color.a = Mathf.Lerp(FadePanel.color.a,128,Time.deltaTime);
}

The effects are slightly different, The first one will be more linear, as for the second one, it will be more ā€œquadraticā€ā€¦ it depends on which you prefer.