Wednesday, October 24, 2007

System of Game Development Tools

In addition the terrain and units files created by the Terrain File Builder and the Units File Builder, I have written a Scenario File Builder that generates a scenario file for each scenario of a new game.

All three files (terrain, units, and scenario) are input to the Game Engine. The Game Engine provides the user interface for the Player and handles game mechanics like movement along paths (when the artificial intelligence is chosen for a side), conducts combat, and keeps track of turn and phase changes. The Game Engine also maintains statistics for each unit such as strength, morale, and combat level.

Tuesday, October 9, 2007

Units File Builder

This week I am working on another game development tool. This one is called a Units File Builder. It generates a file of data related to a unit, a unit being defined as representing a force of some kind (regiment, brigade, battery, etc.).

Data collected by the Units File Builder includes such items as X/Y location, strength, side and type (infantry, cavaltry, etc.) but also any path assignment the unit may have.

A path is a route of five nodes that a unit will follow at a certain turn in the game or under certain conditions.

The file generated by the UFB, like the Terrain File, will be read into a game processor program.

Saturday, October 6, 2007

Terrain File Builder

After posting the finished Agincourt, 1415 game, a game development tool project was undertaken. This effort created a program that facilitates assigning terrain values the hex cells on a game map.

This new tool is called the Terrain File Builder.

The idea is that the Terrain File Builder will generate a file of terrain values for each map hex, which will then be input to future game engines. The TFB assigns a current terrain value to a map hex clicked by the mouse.

Graphic maps files (33 x 22 hexes) for a new game are created in Paint Shop Pro 6, reduced by half, then exported as a JPG file. This JPG file is input to the TFB and, being reduced by half, fits fully on the screen.

Thursday, September 13, 2007

Fatigue at Agincourt

The problem came up on how to model fatigue in the game AGINCOURT, 1415: DARK GREW THE SKY WITH ARROWS.

The French foot armored units (dismounted knights and men-at-arm), weighed down by many pounds of metal armor, had to trudge across a muddy field then melee in the muck. Fatigue had to be an important factor in the battle as the exhausted French were overwhelmed or captured.

Creating a fatigue factor for each unit and increasing it with every turn or movement or melee in the mud was considered.

However, a unit morale factor already exists which is used to determine if a unit routs or is captured. In battle, a unit's morale may decrease due to fatigue (and other factors). A unit suffering a hit and fatigue even more probably might definitely take a morale loss.

The rulel chosen to simulate fatigue in the game was the following. After a fire or melee combat hit, a unit automatically undergoes a morale check where a d6 morale roll is compared to the current unit morale (1 - 4). If the morale roll is greater than the current morale, then the unit takes a morale step loss (eg; goes from good to fair). If an armored foot unit (infantry) is in plowed field (mud) terrain and takes a fire or melee hit, then the d6 morale roll for that unit is modified by +1 to simulate the effect of fatigue in the sometimes knee-deep muck.

In addition, any infantry (armored foot) units meleeing in plowed field terrain take a - 1 melee roll modifier. This also simulates fatigue and the difficulty of effective use of weapons in the terrain by fighters weighted down by armor in the slop.

While not perfect, this model will increase French infantry losses in plowed field terrain. The lowered unit morale will lead to greater probablity of rout and capture.

But the rule is for armored foot units. What about English armored units? The same rule applies to them; they had to fight in the same muddy terrain so when an English infantry unit takes a hit in plowed field terrain, that unit also gets the + 1 morale roll modifier. However, the English knights, in the historical scenario, do not slog for several turns across a muddy field, taking fire (arrow) hits and having to climb over the bodies of fallen men and horses.

Wednesday, August 29, 2007

The Captured French Knights at Agincourt

During the battle of Agincourt, thousands of french mounted and dismounted knights were captured. These were sent to the rear under guard to be held for ransom.

In "Agincourt As A DBA Game" (The Courier #81), Russ Lockwood offers a rule where French knights in melee combat are not eliminated but captured. This is done by moving the unit in question to the English camp area.

Borrowing and expanding on this idea for AGINCOURT, 1415, the rule becomes:

If in melee combat a French knight takes a hit requiring the loss of a Strength Point, the unit is also checked to see if it is captured.

A d6 Capture Roll is generated and compared to the unit's current morale. If the Capture Roll is greater than the unit's morale (morale values range from 1 - 4 with 4 being excellent and 1 being poor), the unit is captured. If not, the unit fights on and may end up being eliminated.

The idea behind this is that the higher a unit's morale, the less likely it will be to surrender and if a unit's morale is lower, the greater chance it may allow itself to be taken captive.

Since the English camp has seven hexes, there is a maximum of seven units that can be captured (only one captured unit is allowed per hex). Limiting the number of captive units models the fact that the English killed a lot of captives when a French attack on the English rear took place rather than have them freed to rejoin the battle.

In AGINCOURT, 1415, if a non-captive French unit enters a camp hex, the French unit in the hex is freed and will become active again. Two English infantry units guard the English camp.

Wednesday, August 22, 2007

The Berserking Longbowmen at Agincourt

Consider the case of the 5,000 English berserking archers at Agincourt. These guys reputedly dropped their longbows and, picking up swords and axes, took on 6,000 armored French knights, which were also on foot, and slaughtered or captured the lot.

Yes, the English had 1000 armored knights pinning the French men-at-arms in place from the front as the English archers swarmed in from the flanks.

But does something seem wrong about this picture?

How about the fact that, under normal circumstances, a heavily-armored French knight could take on several sword-wielding archers wearing only leather jerkins as protection. So how did the French get overwhelmed? When the archers came rushing in from the flanks, why didn't the French knights turn and cut them to pieces?

Two explanations.

First, they were fatigued from fighting and slogging in the mud of the plowed field on which the battle was fought while weighted down by armor. In effect, they were less agile IN THE MUD than the unincumbered archers. On clear terrain, armor versus agility would result in a clear advantage for armor against light infantry (the archers), which is why they were armored in the first place. But, instead, they were in mud.

Second, the French men-at-arms were forced in on each other by the funneling effect of the battlefield and the arrow fire from the flanks. This crowding caused the French confusion, disorder and difficulty using their weapons.

To model these two aspects of the battle in the game, AGINCOURT, two consideratuions were made in the game design. Firstly, melee attacks by longbowmen converted to light infantry against French infantry (men-at-arms) in a PLOWED FIELD (mud) terrain hex will result in a + 1 modification to the d6 mellee die roll in favor of the attacking converted archers (light infantry). In addition, whenever an infantry (men-at-arms) unit type is in melee and is not the only unit in its hex, the meleeing infantry unit suffers a - 1 modifier as an attacker or a + 1 modifier is given to an attacker meleeing against that unit.

Tuesday, August 21, 2007

Defensive Stakes Terrain

One of the interesting and unique aspects of the battle of Agincourt is that, prior to the start of battle, the English longbowmen drove stakes into the ground to serve as a barrier against the French cavalry. Horses would not charge into a thicket of sharpened poles. Without such a defensive wall, the French cavalry would get in among the unarmored and lightly armed archers and run them down.

To simulate this in AGINCOURT, each longbowmen unit is allowed to change one PLOWED FIELD or CLEAR hex into a STAKES hex. Once set, the STAKES hexes are set for the rest of the game and a longbowmen unit cannot convert any more hexes.

Up to six hexes are permitted to be converted to STAKES terrain in a game.

The STAKES terrain can only be removed by French men-at-arms or crossbowmen units moving into the hex, which changes the hex back to it's starting terrain type.

French cavalry cannot enter a STAKES hex. In melee, attacking French cavalry take a - 2 modification of the d6 melee roll against an English unit in a STAKES hex, which guarantees a NO EFFECT melee result. Meanwhile, the longbowmen can continue to fire at the attacking cavalry.

Sunday, August 19, 2007

Longbow Versus Crossbow

At Agincourt, the French had six thousand crossbowmen and the English five thousand longbowmen.

Research shows that both weapons fire about the same distance with the crossbow having perhaps the greater accuracy. However, for the conditions of this battle, the longbow had a decisive advantage: it could be fired many times more frequently than a crossbow. One study shows an average of 12 times a minute for the longbow compared to four times a minute for the crossbow or three to one.

To model this in AGINCOURT, the game, it was decided to add a plus one modifier to the d6 roll for a longbow to hit and to modify the crossbow hit roll by -1.

If to hit a unit must roll a five or a six, the longbow unit will hit on d6 rolls of 4, 5 and 6. The crossbow unit will hit on rolls of only 6. The longbow unit, then, will hit three times as often in the same time interval, reflecting the 3 to 1 firing frequency advantage of the longbow over the slower crossbow.

Friday, August 17, 2007

Agincourt Map Scale

Finding the scale of the Agincourt game map was a little tricky. The scale defines how many yards are in a hex. One source said that longbowmen had a maximum range of 350 yards. That range has to be defined in terms of hexes. We also know that the attacking French battles (lines) were compressed by the narrowing field, making them less effective in melee combat. Compression would be represented by more than one French unit in a hex. So if a French battle starts off X hexes wide, by the time it reaches the English line it should have collapsed into inself to maybe X/2 hexes wide.

The map is 33 hexes horizontally by 22 hexes vertically. Each army is arrayed vertically or up and down on the map. If we let the French battle line be 12 hexes wide, then the English line should be about 7 hexes wide.

We also know that the English had about 1000 men-at-arms, four deep and shoulder-to-shoulder, across their front with archers on the sides. That would put 250 men across the front with three behind each one. If each man requires one yard of space then this is a 250 yard front.

If we use five hexes of the seven-hex front for the English men-at-arms, then each hex must equal fifty yards.

Since longbow maximum range is 350 yards, we now know that most of the English longbow units must be no farther than seven hexes from the French lines at the start of the battle since it was a galling rain of arrows that spurred the French cavalry to attack.

With 1000 English men-at-arms men spread over five hexes we know that each hex holds 200 men. We want Strength Points between 1 and 10. If we let one SP equal fifty men-at-arms then the five English men-at-arm units each will have four Strength Points. Five is a good number for the total number of English infantry because the English archers numbered 5000 and we don't want too many units on the map.

Tuesday, August 14, 2007

Agincourt Project

Several completed games need only dusting off to be uploaded but they can wait. It was decided to take a break from play testing existing games and develop a new game.

The project selected is Agincourt, 1415. Besides the fun of developing a new game, this project will serve another purpose. The step-by-step development of Agincourt, 1415 will be recorded in the Designer's Notebook of the web site. Hopefully, it will make a good example of what goes on when developing a computer-based board game.

The battle of Agincourt pitted Henvy V's longbowmen against the flower of French knighthood. Many brave French knights died and the victor Henry V had a play written about him by a guy named William Shakeapeare.

It took about three or four hours to put together the game map which can be viewed in the Designer's Notebook. The map represents the historic battlefield which funneled French troops between dense woods on either side across a muddy, slow-moving plowed field into the teeth of armor-piercing English longbows.

Monday, August 13, 2007

Engineers at Blenheim, 1704

The 1704 battle of Blenheim made an interesting game. The supposedly invincible Franco-Bavarian army army of Louis XIV, the Sun King, was located on higher ground with swampy terrain and the Nebel river protecting their front. The town of Blenheim and the Danube River anchored their right while heavy woods guarded their left. The Allies under John Churchill, Duke of Marlborough, and Prince Eugene of Savoy, were faced with crossing these obstacles and attacking uphill with French cavalry waiting.

Marlborough ordered engineers to repair the stone bridge across the Nebel and to assemble mobile pontoon bridges for other crossings. Meanwhile, pioneers with troops assisting, bundled bound branches and threw them into the swamp, across which they laid planks. This work was done after infantry and cavalry first swam across the Nebel to provide cover fire.

To simulate how the Allies dealt with these terrain obstacles, a special unit called an "engineer" was created for the Allied side. These units have the ability to convert swamp, river and damaged bridges to "bridge" terrain. Wherever an engineer unit moves, the computer converts the above mentioned terrain to bridge terrain.

The primary source for information on this battle is the excellent book by Charles Spenser, Blenheim, Battle For Europe (2004). Mr. Spenser is directly related to John, Duke of Marlborough. I am fortunate to have a signed copy of the book.

Sunday, August 12, 2007

Web Site Tweeking

Waterloo:Give Me Blucher or Give Me Night was put up last week and the web site has been updated to reflect that. Also started on the Game Development section of the web site, which concerns how to go about developing computer-based board games.

Waterloo is the first game using the Napoleonic Engine. Borodino is the second. Borodino is done and will be play tested soon if no other projects gets in the way.