Tint Projectiles Based on Player
If you want the missiles of your unit to be colored based on the player that casts it, this tutorial is for you!
The fact that I am using 4 upgrades, requirements, validators, events, etc. is because I'm going to make the game tint the projectiles of 4 different players.
General concept
We'll use Validators to detect which Custom Upgrade a player's caster-unit has. We'll also have to give this upgrade to the players via triggers.
Upgrades
Create 4 blank upgrades and you're done for this part!
Requirements
Create 4 requirements of Tech Type "Upgrade".
In the Requirements + field, remove anything you see. From there, add a new value (right click -> Add Node) to the Use field and select "Equals".
Now, add a new value to the Equals: "Count Upgrade". From there, choose the corresponding upgrade as the Alias and select Completed as the State.
You'll also need to create a new Node that will correspond to the Upgrade Count. Do as follow: create a new value to the Equals, select Constant and set it to 1.
You'll do this for the 4 requirements, one different upgrade per requirement, but always setting the Constant to 1.
Validators
Create 4 Validators of type Player Requirement.
Make sure the field Validator - Player + is set to "Caster Origin".
Change the field Validator - Value to the corresponding Requirement.
Actors
Go to your missile unit (Ammo Unit)'s Actor tab and change the Event - Events +: right-click to make a new Event. The Event's type should be Actor Creation (since we always want the actor to be tinted).
Now, right-click on the Event and click on "Add Term". Change the Term type to ValidatePlayer and change the Validator to one of the 4 you've created.
Next step is to set the Action's "Msg Type" to Set Tint Color. All you'll want to change in this is the "Color" field.
Repeat this 3 more times, adding a new Event for each player (remember we're making this for four players, hence the fact that we're doing 4 times everything).
Triggers
Now, using a Map Initialization event, you'll want to create a "Set Upgrade Level For Player" action and give a level 1 upgrade for all the 4 players (remember you've created 4 different upgrades, one for each player).
Other techniques
There are multiple ways to achieve this. Some are easier, but may not fit most of the situations.
Alternative #1
We could use 1 upgrade and 4 constants (the difference would be in the triggers: you'd set a level value to the upgrade instead of different upgrades of level 1).
Alternative #2
We could use resources.
The only thing this technique requires is 4 different Validators of type "Player Compare Resource". From there, you change the fields Validator - Compare, Validator - Resource and Validator - Value. Don't forget to verify that the Validator - Player + field is set to "Player Origin".
As for the triggers, we'd have to use a "Modify Player Property" action.
IMPORTANT NOTE: You shouldn't use this technique if the resource amount a player has might change during the game.
