Desert War: Designing Brevity

[bcgames]

In this DevBlog I will discuss the techniques and procedures I used to design the Operation Brevity scenario. There are many ways to approach scenario design using the Desert War engine--this is just one of them. Enjoy.

[bcgames]

Before we start, let's start on the same sheet of music. Find attached the Operation Brevity scenario (DRAFT). Unzip this file in your My Documents/My Games/DesertWar/scn folder.

UPDATED: 11 DEC 2018...

[bcgames]

If you are interested in how to make a scenario map, go here:

tm.asp?m=4474692

If you are interested in how to make an Order of Battle for a scenario and how to place it on the map, more to follow in a later post.

This first lesson is on a topic I am dealing with right now--scripting the AI.

So what do I do?

Given a side (Axis or Allies)...

1. Develop potential enemy courses of action. What are the most likely and most dangerous ways/means the enemy might employ to achieve their objectives? How to do this? Consider the enemy's HQs and what missions that might be given if the enemy attacked and goes left, right, up the middle or advances on a broad front. If the enemy defends, what to do if his main effort is on his right, left, center or dispersed across the front?
2. Identify the HQs requiring instruction. You'll want to issue instructions to an organization as opposed to individual units using this scripting engine. Issuing to individual units is tedious and circumvents the "self-defense" attributes AI units have intrinsically.
3. Sketch some courses of action (COA) that show what friendly HQs will be ordered to do if the enemy indicates his intentions (as revealed by friendly reconnaissance efforts).
4. Script the friendly actions identified for each enemy course of action.
5. Test to see if friendly scripted actions work as intended. Tweak and test until you see what is expected.

What does a COA sketch like like? Sort of like this:



At the top of the COA sketch, I've listed the relevant HQs for the Axis AI response. I see all Axis HQs will require movement/attack orders except Frontiera; these guys will get one instruction--Hold At All Costs. You of course can order them to do something different.

COA1 assumes the Allies Main Effort will occur in Area B. The Axis reaction will be to screen with recon units forward of the Allies advance while the Axis Main Effort swings out to the WEST (left) and SOUTH and the EAST to hit the Allies in their WEST flank. The Axis advance culminates with an advance on Halfaya Pass. Axis air effort will split between Ground Support and Ground Attack missions.

[bcgames]

Axis COA 2 assumes the Allies Main Effort (ME) is in the WEST (left). Axis recce will screen forward of the enemy's advance. Kampfgruppe Crammer will maneuver to protect the WEST flank of the Axis ME. Axis ME will attack to seize Ridotta Capuzzo and Halfaya Pass. Supporting Effort by KG 5.Pz attacks to seize Sollum Barracks, Sollum, and assists in capturing Halfaya Pass. Axis air focuses on Ground Support.

[bcgames]

Axis COA3 assumes an Allies broad front strategy. Axis recce screens advance through Area A. KGs 5.Pz and Esebeck, as the Axis ME, attack to seize Ridotta Capuzzo and Halfaya Pass. KG Crammer secures the WEST (Left) flank of the Axis ME. Axis air focus is on Ground Support of the main effort.



Now...how do we script all this?

[bcgames]

Here are the missions of the opposing sides:

Capture Halfaya Pass, drive the enemy from Sollum and Capuzzo, inflict as much loss as possible and exploit success towards Tobruk as far as supply allows without endangering British forces.

Defend to retain Halfaya Pass, Sollum and Capuzzo.

Here is where every body starts the scenario:



The Axis player starts the game with three major components: KG5.Pz, Raggruppemento Frontiera, and the reconnaissance screen. There is also a small garrison force at Bardia. On Game Turn Two (GT2), the Axis receives KG Crammer as a reinforcement; on GT4, KG Esesbeck.

The Allies player starts the game with five major components: A reconnaissance force, Coast Force, 22nd Guards Brigade, 7th Armoured Brigade, and 7th Support Group. There is also a small line-of-communications security force.

The focus of the AI scripting will be on moving these major components around based on enemy action.

[bcgames]

4. Script the friendly actions identified for each enemy course of action.

So what are the "enemy courses of action"? Let's create three of these then see what we've got. The "enemy" in this case are -- The Brits!

Course of Action 1 (COA1) will be something close to the historical Allied plan.

* Coast Force and 22nd Guards Brigade attack to seize objectives at Halfaya Pass, Sollum Barracks, Musaid and Ridotta Capuzzo.
* 7th Armoured Brigade attacks to engage any Axis forces attempting to reinforce the frontier.
* Recce and 7th Support Group protect the left (WEST) flank of 7th Armoured Brigade.
* PAVO secures lines of communications to the EAST edge of the scenario map.
* Allied Air efforts will focus on attacking Axis ground forces attempting to reinforce the frontier.

[bcgames]

COA2: Fast Finish -- Allies attack to secure objectives simultaneously--then dig-in and hold at all costs.

* Coast Force and 22nd Guards Brigade attack to seize objective Halfaya Pass; then become Allies reserve.
* 7th Armoured Brigade attacks to seize objectives Musaid and Sollum Barracks.
* 7th Support Group attacks to seize objective Ridotta Capuzzo.
* Recce screens left flank of 7th Support Group.
* Allies air effort focuses on delaying Axis reinforcements through interdiction missions.

[bcgames]

COA3: Distraction and Progression. Prevent interference by Axis armored forces while 22nd Guards and Coast Force seize all objectives.

* Coast Force and 22nd Guards Brigade attack to seize all objectives (Halfaya, Sollum, Capuzzo, Musaid); then become Allies reserve.
* 7th Armoured Brigade attacks to engage KG5.Pz.
* 7th Support Group attacks to seize Sidi Azeiz; block Axis reinforcements coming from the WEST.
* Recce screens left flank of 7th Support Group.
* Allies air effort focuses on ground attack against Axis reinforcements.



What's Next?

Given the COA laydown shown above, we'll build the script for Allies COA 1 (the historical plan)...

[Alan Sharif]

Very interesting. Thanks for sharing.

[bcgames]

Scripting Allies COA1 - The Historical Plan

To help build this COA script we go back to our sketch and add the hex locations (x,y) we need to get the various Allies organizations moving/acting according to plan. This doesn't have to be pretty. As long as you understand your sketch--you're good.

[bcgames]

Now let's write our first scripts. Open the Brevity scenario in the editor and select the AI tab.

We'll start with Coast force and then work our way over to 7th Armoured Brigade and 7th Support Group way out in the desert. We see from our COA sketch that Coast Force task is to attack Halfaya Pass (hex 26,22) in cooperation with 22nd Guards Brigade. This operation will take a minimum of two scripts--one for Coast Force and one for 22nd Guards. Here's how to do it...

ATTACK is the default task when adding an entry. We want to tell Coast Force where to attack so we'll enter the coordinates for Halfaya Pass (26,22) in Resp Hex_Y and Resp Hex_X

For the script to execute, we need a trigger. We want Coast Force and 22nd Guards to launch their attacks starting on game turn 1 so enter 1 in the Trig Turn cell.

Now do the same for 22nd Guards. Add an entry, select 22nd Guards as the Resp Org, enter Halfaya Pass X,Y location, and enter 1 in the Trig Turn cell.

OK...we've scripted the attacks for two of our six organizations. Now let's save the scenario, exit the editor and run it as an AI vs AI game to see what happens.

[bcgames]

If you scripted the AI outlined above, you might see something like this if you ran the scenario AI vs AI:



We didn't script any artillery fire--so what gives? Well...there are two things. The first is Staff Assist AI. The AI is programmed to help the Scenario Designer with his task of scripting and AI. If you don't commit artillery, air or ground assets in your AI scripting, the AI will assume you, the scenario designer, want the AI to decide where and when to commit unit support and/or asset support. If you--the Scenario Designer don't tell us what to do--we'll fill in the blanks as we see fit (so sez the AI).

[bcgames]

Now let's throw in some supplies for the AI. Move+ supply will double the movement factor of the units in an organization; Combat+ will double the attack factor of non-artillery units and quadruple the attack factor of artillery units. Given that 22nd Guards has further to go to get to Halfaya Pass, let's assign them Move+ supply for GT1. Coast Force and 22nd Guards will be in position to conduct a combine attack on GT2...so let's assign both of these organizations Combat+ supply on GT2. Here's how it looks:

[bcgames]

Now run the scenario to see what happens.

[bcgames]

If you ran the scenario AI vs AI, you'll see that one turn of Combat+ supply is not going to see the capture of Halfaya Pass before GT5 (item 1 in the attached image). What to do?

This is where Max Run comes in. Max Run has a default of 1. It means the AI will perform the assigned Response Task (Resp Task) once and then terminate the script when the Resp Task has been accomplished. IOW, we assigned Combat+ supply on GT2 with a Max Run of 1. Combat+ supply was provided on GT2 and therefore the script terminates. You could re-write the Combat+ script only execute on GT3 or... a better solution is to change the Max Run for script id#4 to 2 or more (see item 2).

Let's enter a Max Run of 3. This means the script will run for three game turns (GTs 2, 3, and 4) before it terminates. Re-run the scenario AI vs AI to see how we're doing. Barring any bad die rolls, looks like Halfaya falls on GT4 not GT5 (see item 3).

[bcgames]

All this previous scripting is nice and instructive...but...

We need the AI to take down Halfaya Pass faster than GT4--there's more for the 22nd Guards to do before the Axis can react to the AI in force. Here's a way.

Let's add some air recce to the equation. Also, some re-stacking of the 22nd Guards initial set-up will make sure all the Matilda tanks get into the fight fast. These tweaks and we get a take-down in two (item 1).

To allocate Air Recce assets, let's Add Entry (id#6), and select airForce from the drop-down menu for Resp Unit. Select an air recce unit and assign it to look at Halfaya Pass (26,22). Trig Turn will be GT1; Max Run = 1. With better intel from the air recce mission the AI artillery will be more effective when the AI attacks (item 2).

While we're at it, let's save some ammo. Set Combat+ Max Run from 3 to 1 (item 3).

Run it. Boom. Take-down in Two.

[bcgames]

Not much interest here. If you have any questions on this topic, just let me know. I'm off to patch work and the Eastern Front.

[bcgames]

Operation Brevity scenario is ready for two player. I've posted PBEM+ challenges for both the Axis and Allied sides. Download the latest Operation Brevity files in the second post above and the challenges should appear in your Desert War PBEM+ interface. If you have the time, let's have a go.

[bcgames]

I know this scenario has been played head-to-head via PBEM...any feedback? Errors? Play balance? Any other observations? What say you?