Question Change color of generated object

Hi guys, I have a problem that may seems easy to you but I had tried a lots of suggestion found online. The main problem is that I'm still learning of course and I don't understand all the mechanics. This is my first 100% game build by myself and I'm trying to find a solution to probably a problem that I had made inside my logics. I'm pretty sure the solution is simple but...

Down you can see a portion of my script related to creation of rectangles with a random color from my array.

Code (CSharp):

1.  
2. "brickPrefab class"
3.  
4. // variables
5. public Color[] colorPicker;
6. private Color selectedColor;  
7.  
8. private void Start(){
9.       int randomColor = Random.Range(0, colorPicker.Length);
10.       selectedColor = GetComponent<Renderer>().material.color = colorPicker[randomColor];
11. }
12.  
13. private void GetHit(){
14.       // change color of the rectangle here
15. }
16.  

In my GameManager script

Code (CSharp):

1. public GameObject brickPrefab;      // brick
2.  
3. private void Start()
4. {
5.       // bricks generator
6.         for (int i = -4; i < 5; i++)
7.         {
8.             for (int z = -2; z < 2; z++)
9.             {
10.                 Instantiate(brickPrefab, new Vector3(i * 2, 0.25f, z * 1.2f), Quaternion.identity);
11.             }
12.         }
13. }

Till this point I'm pretty happy, the game works fine. Now I want that the rectangles changes color (maybe alpha) when hit by enemy (method in brickPrefab class, GetHit() ). And I can't make it work. My prefab is a rectangle wit a general material with white color on it.

Do you have any suggestion?

 

You can just set the renderer's material.color again to change the color in your GetHit() method.

 

Ah yes, I can write inside GetHIt method

Code (CSharp):

1. this.GetComponent<Renderer>().material.color = Color.black;

and it will work. But I would like to have 2-3 state od changes.

0 hit = 100% alpha
1 hit = 75 % alpha
...
...

The problem is that I don't know how to change the alpha of the color. On screen I have, let's say, 40 rectangles and every one have a different colour. Of course I can reassign a random colour to the rectangle when hitted but I will preffer an alpha change to indicate a state o decay

 

That part is simple. Basically you just need to make a new color with a different alpha value (which you can base off another color):

Code (CSharp):

1. public static Color WithAlpha(Color color, float a) {
2.     return new Color(color.r, color.g, color.b, a);
3. }

Then just assign the new color to the renderer's material. Just remember that the alpha value (and r,g,b) should be a number between 0 and 1.

 

I've tied to but indeed I had made some mistake.

Code (CSharp):

1. private void GetHit()
2. {
3. // get original material
4.             Color originalColor = GetComponent<Renderer>().material.color;
5. // set new color based on new method
6.             this.GetComponent<Renderer>().material.color = WithAlpha(originalColor, 0.5f);*/
7. }
8.  
9. public static Color WithAlpha(Color color, float a)
10.     {
11.         return new Color(color.r, color.g, color.b, a);
12.     }

Nothing happen when the rectangle is hit

 

I see a "*/" at the end of line 6 of your code snippet. Either that's a copy/paste error, or all of your code up to that point is part of a large block comment. If it's part of a comment, it won't run.

 

Sorry the */ is an error for testing. The actual code don't have it.

 

Does that code actually run? If you put a Debug.Log() statement around there, does it show up in the logs?

 

Yes, if I put a Debug.log() insite WithAlpha method I get a log every time the rectangle get hit. Maybe something is wrong with the method to get the original color and than put it back to the same rectangle