How to create a state based traffic signal?

Question

I want to create a traffic light for a Unity3D game. I will model it in blender.

What is the best way to control this light in a unity scene?

One way I could think of is to change texture of say red light from dull red to bright red, when it is time for red signal. But I am not sure if this is possible or a good strategy.

Answer 1

You can access the material of the lamp object in the Unity-API.

public GameObject lampObject;
public bool isGreen;
public Color greenColor, redColor;

private void Update()
{
    lampObject.material.color = isGreen ? greenColor : redColor;
}

This will set the material color of the lamp to a specified value you can edit in the inspector. It is also possible to lerp to the target color with Color.Lerp.

var targetColor = isGreen ? greenColor : redColor;
lampObject.material.color = Color.Lerp(lampObject.material.color, targetColor, 0.1f);

The 0.1f will control how fast the color will blend to the target color.

Other possible ways would be -as you said- changing the texture of the lamp object texture by accessing lampObject.material.mainTexture but I dont see any reasons to change the whole texture just for a traffic lamp color.