CDK Mission Editor: Variables

Variables in mission editor are used to store information like text, numbers or booleans used for creating true or false statements, they can be used to optimize code of your mission and also to create things that are normally impossible without using them.

If you create a string variable named t1_unit_01 you will be able to see it in Target or Object tab which you can find in actions similar to unitSetProperties where you can select AI or player units, its name will be displayed as @t1_unit_01, it will be displayed similarly in other actions too.

As mentioned before, they can also be used to optimize missions, but only when you need a really high amount of triggers that do perform similar functions, in case of small mission you won’t even notice a difference and usually you will need more triggers than when just using simple actions without variables, so this article will explain how to use them and show a good use of them.

Basics

How to create a variable

1. Choose on the side toolbar Variables, you can find it under Triggers tab.
   Now you should be able to see a window with multiple tabs that can be pressed, Add for adding new variables, Edit for editing, Del for deleting and Up and Down to move them.
2. Press Add to add a new variable.
   After pressing it a new window should appear, you can select a name for it under Variable name: and select its type under Variable type:, there are 10 of them, but for now I’ll only explain how to use string (text), integer (number without a fractional component), real (number with a fractional component) and bool (used for creating true or false statements)
3. Set the variable name to t1_unit_string_01 and it’s type to string. 
   Now you should have created a new string variable, the next thing to do is set its value and assign it to something
4. Select created variable.
   After selecting there should appear a new field where you can set its value
5. Set the variable value to t1_unit_01.
   Now you need a new action where you can assign this variable
   
6. Go to the Triggers / Missions Obj. Navigat tab, find an unitSetProperties action and create it.
7. Press object and select @t1_unit_string_01, then scroll down and enable cannotShoot option.
   It should assign a variable to this action and give it a simple property, now we need a unit which will use it
8. Create a new armada unit and call it t1_unit_01 and make it a player unit.
   If everything went without any issues then your unit shouldn’t be able to fire and that will mean that you properly assigned a variable to unitSetProperties action

Ways of storing information in variables

Editing variable value manually

Go to the window with Variables, simply select one of them and just set it’s value.

Sometimes it’s a good idea to assign some important actions and conditions to variables and then just edit them by changing variable value in the .blk file.

Using varSet (Int/Real/Bool/String) actions

Create a varSet action, in the Var tab select that variable which you want to edit, then set it’s value, you can also import this value from other variable using input_var option.

Using varAddString action

This way you can add a text to existing string variable by adding a value in the field with same name or a number and set selected amount of shown digits (for example if you add a 3 number and set digits to 2 then it will be shown as 03), you can also input all these values from other variables

Using varModify action

To do operations on selected number

Using varSetRandomInt action

To just let the game choose a random number from selected range

Using varGetIntFromString or varGetStringValue

Example of how you can set it:

Current variables:

Now I want it to set the string to the name of a unit that has a higher number (by 1)

Actions:

• unitSetVar (var = “t1_unit_string” value = “”) — to clear value of selected string
• unitSetVar (var = “t1_unit_string” value = “t1_unit”) — sets the value to that with which starts name of AI
• varModify (var = “t1_unit_int” operator = “add” value = “1”) — adds 1 to existing number
• unitAddString (var = “t1_unit_string” input_var = “t1_unit_int” digits = “2”) — adds the number of the next unit

After that this variable should be shown as t1_unit_13.

Examples of use

Creating a set of triggers that checks multiple areas for units

This set of triggers is meant to check if there are units in a selected area, then if there’s at least one unit from the A or B team in it the mission should mark this area on the minimap with a colour depending on which team is at this moment in that area. If there are both teams in the same area then it should give it white neutral marking on the minimap. The mission should have 36 of those areas and they should be placed next to each other.

To make everything behave as intended, you need 8 triggers, one that checks all areas at the start of mission, one that checks all areas later when the first one is disabled, three for checking if there are any units in them and from what team they are, another three triggers to mark all areas and obviously variables, in this case 42 of them.

Adding variables

The first step to get things done is to add variables that you will need for your mission

Adding areas

The second step is to add areas

• Create 36 box areas that are placed next to each other

It should create one big 6×6 box, so it should have 6 columns and 6 rows. Don’t forget to set their size to 2000×2000 meters.

They can’t overlap with each other because if that happens it can break the mission, there should be at least 5 meters of free space between areas

• Rename all areas to b_area_01, b_area_02, b_area_03 etc.

Remember that they can’t be named in random order, it is the best to name them from the left to the right or in reverse order

Creating triggers that checks all areas at the start of mission

First trigger will responsible for creating a name of areas which will be later checked in other triggers for the number assigned to every area (1, 2 or 3)

Basically it works like that, first_time_check_all_areas sets the value of b_area_string (for example b_area_01 — name of the area that is going to be checked, it will be needed for showing icons) and b_area_string_check (for example b_area_01_int — name of the variable (it’s stored value, 1, 2 or 3) that is going to be checked) that is going to be checked, then activates when_t1, when_t2 and when_both triggers that will shown an icon on the minimap with corresponding color

Three similar triggers which the main function will be to add an icon on the minimap

• Trigger name = "when_t1" — it will check the number assigned to b_area_xx_int (xx = number) variables, 1 — set the icon color to A team
• Trigger name = "when_t2" — it will check the number assigned to b_area_xx_int (xx = number) variables, 2 — set the icon color to B team 
• Trigger name = "when_both" — it will check the number assigned to b_area_xx_int (xx = number) variables, 3 — set the icon color to neutral team (white)

This one is for when_t1 Every time only one of these triggers will be used and the rest of them will abort should they not meet the condition

Now you will need to copy this trigger to make it work for every colour (blue, red and white)

• Copy this trigger two times and set the name of copies to when_t2 and when_both, then change their values in varCompareInt to 2 for when_t2 and 3 for when_both.
• Change the color of icon in missionShowMapIcon (under actions) to Team B for when_t2 and White for when_both.
• Change the target in triggerDisable action, switch it to @when_t2 for when_t2 and @when_both for when_both.

Now go back to the window with Variables and set values of all b_area_xx_int (xx = number) variables to 1, 2 or 3. If you did everything properly then the mission should show blue, red or white icons on the minimap.

Creating triggers that give a number to b_area_xx_int variables and keep checking them until the mission ends

This trigger works like first_time_check_all_areas, the only big difference is the part under Actions, this time it is used to reset trigger state when b_area_int it reaches 36, other difference is a trigger that is enabled at the end of Actions and Else, it is set to check_if_no_one_in_area now.

The next set of triggers will change the number of b_area_xx_int variables, for that you need to create three similar triggers, which will check if there are any units in areas.

After that, it will work exactly like in the previous part (3.).

If you did everything properly, then now this entire set of triggers should work like it was explained in the description of this section.You can increase the number of areas but you also need to increase the value of b_area_amount_int variable if you want to do that.

Sample mission

• Link to the multiplayer mission that contains this set of triggers (Remember that you need to remove https:// part of this link to make it work in War Thunder)