Common technical details
- Turn-based/simultaneous execution
All three games share the same concept; turns are divided into a planning and an executing phase. While the planning phase can, in single player mode, last as long as the player needs to give orders to all their units, the executing phase always lasts 60 seconds of real-time. Both sides, either computer or another human, enter their orders before the execution phase takes place. This is known as the Wego system. During the execution phase, units carry out their orders, but the player cannot influence the result and is limited to watch, replay and move the camera. All games offer to play individual battles (ranging from 15 to 60 turns, or 120 turns in Barbarossa to Berlin and Afrika Korps) or operations, linking a series of battles. See Scenarios below for more information.
- Editor
The games offer an editor to create maps and battles. The editor is a simple, top-down, tile-based affair that allows mappers to place any of the game's terrain tiles anywhere on a square grid representing the map and change the elevation of each tile individually. Buildings, roads, forests, fields, rocks, and water can be placed, in addition to the forces that will be disposed to each side, if the map is designed as a scenario with fixed forces. Also, in creating custom scenarios, players can write their own text introductions to the scenario; one text file for both sides, and two other side-specific text files that set up the battle and the order of battle for each side. Players can also write their own victory/loss texts.
The series also offers a "quick battle" option. Player(s) can only edit some general parameters (mission type, year, region) and then the computer creates a random map. Units can be selected by the computer or can be bought using points. Each unit has a value in points depending on type, for example a tank costs more than a squad of riflemen. Optionally, for added realism, when buying units the rarity of the unit can be taken into account. This keeps the battles true to the time period, as players trying to use rarer units are penalized. Additionally, scenario designers often carefully research a battle to create accurate historical battles.
- Multiplayer
All games offer to play as a single player versus a customizable AI, or to play against a human opponent by hot-seat, email or TCP/IP.
- Scale
Game is at the squad/team level with individual vehicles and guns represented. Depending on the scenario, the players can command forces ranging from a platoon up to a reinforced battalion. Ideally, the game operates at the company level with the player taking on the role of a company commander. Given the large size of the maps in Barbarossa to Berlin and Afrika Korps, with enough computer processing power a player could deploy a brigade/regiment on a single map.
Game concepts
- Morale and Leadership
Continuing the theme first presented in the Close Combat series of tactical computer wargames, Combat Mission models the morale state of soldiers in the game, with different levels ranging from OK to Routed. Fatigue levels are also modelled, and beginning in Barbarossa to Berlin soldiers are modelled with varying base levels of fitness; Fit, Weakened or Unfit. A final consideration is experience and training, which Combat Mission assigns to units ranging from Conscript to Elite.
While every unit will try to follow commands, units under fire will react to that fire by taking cover, breaking or even fleeing in panic. Units will recover from lowered morale states, though some may be permanently affected for the duration of the game. Leadership is also modelled in the game, with headquarters units influencing the morale, firepower, and stealth of units under their command.
- Casualties
A hit on an enemy unit does not always mean destruction. Infantry units in the game represent from 1 to 15 soldiers, and wounded/killed men disappear from the simulation. When a unit has lost all available manpower, it will show up on the map as a dead soldier icon.
Armour penetration in Combat Mission is given realistic treatment. Partial penetrations, spalling, and non-fatal penetrating hits are all modelled in the game, with realistic ballistic stats for both armour and armour-piercing weapons. Catastrophic damage to vehicles is modelled, with real life tank models prone to fires being equally prone to "brewing up" in the game.
- Scenario types
There are two types of scenarios in the first Combat Mission series; Battles and Operations. Battles are standalone scenarios, either randomly generated Quick Battles or pre-made by scenario designers. Operations are a series of two or more battles played over the same terrain, linking these fights into a greater overall context. Forces are carried over from one battle to the next in an operation, but often units will have ammunition replenishment and new units will be added to the player's army. Operations have different objectives than scenarios; sometimes winning depends on advancing to the end of the map, for example.
The second Combat Mission series will have two types of scenarios; Battles as in 'CMx1', and Campaigns, which will be story driven. Like the Operations in 'CMx1', the 'CMx2' campaigns will carry over forces from one battle to the next, but individual promotions will be possible and repair/retention of weapons is expected to be more realistically handled.
- Victory
Victory is assessed by four factors; inflicting casualties, holding key terrain (when indicated by the scenario by flags), exiting units from the map (when indicated by the scenario), and capturing enemy soldiers. A computation of points is done after each scenario.
- Spotting and fog of war
The player can zoom out and watch the battlefield from a bird's eye perspective as well as zoom in and attach the camera to a single unit. However, due to the games' fog of war features, the player will only see the enemy units their own units have spotted. Each unit has its own line of sight that is blocked by obstacles like hills, houses and trees. Night, dust, weather, smoke or sandstorms all reduce the line of sight.
Sometimes units can hear the enemy. That is represented with a grey symbol featuring a red question mark and the text "sound". Sound contact information tends to be less precise than visual information. Also previously spotted units may disappear again, if they hide or move out of line of sight. Long-range visual contact is not always sufficient to correctly identify an enemy unit.
- Line of sight
Every unit under the player's control can be clicked and forced to display a graphical line of sight representation. The line of sight is sometimes the only way to decide if a unit can see a specific spot or not.
The first generation series of games used a concept called "absolute spotting" while the second used "relative spotting."
..."relative spotting"...is...(when) each unit knows what it has/hasn't spotted. Right now CM uses what we call "absolute spotting", which means once a unit spots something it is spotted. There is absolutely no sense of if anybody has spotted the unit before or after on a unit by unit basis.
Relative spotting is something we had wanted to get into CMBO. Unfortunately, it is more complicated thing than it might look like at first. Each unit would only be able to see/shoot at units that it was aware of. This means lots and lots of spotting calculations going on all the time even though units have already been spotted. It also means that there has to be some sort of user interface to distinguish between units spotted by other units and units spotted by the currently selected unit. If I thought back to when we realized this was too much to bite off for the first version I am sure I could remember a few other significant reasons why we didn't go with relative spotting right away [1]
- Weather and terrain
Weather and terrain is highly variable and includes different visibility (sunny, fog, precipitation, night), ground cover (mud, snow, dry ground), temperature (Not in Beyond Overlord, with extreme temperatures affecting vehicle and weapon performance) and ground type (dirt, sand, rock). Terrain is laid out in 20 metre tiles in 'CMx1' (to change to smaller tiles in 'CMx2') and includes terrain types appropriate to each individual theatre (western Europe, eastern Europe, the Mediterranean) including brush, marsh, light trees, forest, pine forest, hedges, low fences (wooden and stone), graveyards, small and large buildings, stone and wood buildings, small huts, steppe, desert, rocky ground, palm trees, cratered ground, dirt roads, paved roads, deep and shallow fords, rivers, and various types of bridges.
Sound and music
There is no background music in Combat Mission except during the title screen. The in-game sound consists of wind noise, rain, and background explosions.
Different vehicles have different engine sounds, while the troops will shout different phrases in their native languages as a cue to the player that units are moving, coming under fire, panicking, low on ammunition, surrendering, or other battlefield occurrences. Different weapon systems also have different sound effects.
Physics engine
There is a realistic physics engine in each of the games. Tanks can seek a hull-down position behind obstacles. Vehicles, being hit while moving at full speed, will sometimes continue due to momentum before coming to a halt. Tanks can push lighter vehicles out of the way. Specific details such as ground pressure are taken into effect, to the point where a heavy tank will get stuck in the mud; while a jeep will be able to drive right through the same area.
Unit commands and tactics
Depending on the type of units, each unit has a set of commands available. Movement orders are given by waypoints and varying speeds and levels of stealth can be selected. The unit will try to follow directions until the unit comes under fire or they run into a minefield. Tanks have the ability to hunt for other tanks, seeking a hull-down position behind obstacles or "scoot & shoot" by firing and then retreating to a pre-selected hiding spot. Infantry units can all hide, sneak and move. Most units can run for a while, and many units like rifle squads can "advance" or "assault" which simulates the use of fire and movement at the squad level, with some men firing from cover while others advance in short bursts of movement. Soviet units can launch human wave attacks. It is possible to fire at spotted enemies but also give Area Fire commands.
While units can be ordered to perform certain specific actions (assault, fire, move, hide, etc.) actual unit tactics, in the sense of manoeuvring, occupying an objective or laying an ambush are entirely dictated by the player. Units under human command will not move (other than fleeing when broken or shaken) unless specifically ordered to do so. They will fire back if fired upon and tanks will pop smoke and often retreat a short distance if they register the targeting laser of a hostile MBT or other heavy vehicle.
In the World War 2 series of games Infantry squads (particularly the Americans) can be broken down into 3 teams. In the modern Combat Mission games (Shock Force and Black Sea) Infantry squads can only be broken into a maximum of two teams within a particular category - Scout, Assault, Split and Anti-tank. Each of these categories creates a team of that specific type using the appropriate soldiers. The remaining unit members are bundled into the second team.
For example, selecting Scout will create a two-man Scout (Team 1) while placing everyone else into Team 2.
Armoured units do not break down into separate teams, the individual vehicles being considered as separate entities.
Realism
The game engine handles various aspects of the battlefield differently; ranging from very detailed (like tank armor) to very abstract (like infantry movement). The two game engine variants, 'CMx1' and 'CMx2' also have significant differences in processing capability, ability to handle large numbers of units or complex models/maps and iterative AI complexity, with CMx2 being a much more robust, stable and flexible development of the core game engine.
- Infantry in the first series of games (which use the 'CMx1' engine) is handled more simply than other parts of the game: A squad of 12 men is displayed as 3 soldiers and a numeric value displaying 12 in the status bar if you click on the unit. A two-man bazooka crew is displayed as a single soldier and a value displaying two in the status bar. However large a squad in manpower is, it will always face and move as a single unit. Large infantry units can be split into smaller, less effective units with a corresponding loss in morale.
The 'CMx2' engine, used in Combat Mission: Strike Force and onwards, provides a much more detailed treatment of Infantry. Individual soldiers are modelled, animated and tracked, along with their own individual AI within the game. So a platoon of 8 infantry contains 8 individual soldiers which are treated as separate entities united by a common unit AI, but with their own set of characteristics, including even their name.
For example, the real-time Morale status of each soldier is tracked, although it is their current unit (squad, team, platoon, etc.) as a whole which will break or rally. Each soldier will scan, aim, fire, throw grenades, reload, cower as individuals while operating as part of their unit. If their platoon is ordered to move every soldier will attempt to do so but will still react to events around them, such as suppressive fire, artillery explosions, mines, etc.
- Some aspects are simplified for clarity and to avoid overloading the engine with too much detail. Experience, motivation and fitness are measured on a per unit scale, with the smallest being a team (such as a machine gunner and assistant, or a sniper duo) or an individual tank or IFV. These soft factors can be manually adjusted from the battalion level down to the individual teams or vehicle - so a mechanized infantry company could have a collective Veteran experience level, but 1st Platoon is given Regular experience, while its 1st Squad could be put as Conscript.
- Terrain is handled in 20 metre tiles. While you see a group of trees in the battle graphic, you can turn the (visualization of the) trees completely off and be left with a dark-green area of the ground instead. This area has a value for providing cover, providing camouflage and hindering movement. The value always acts for the complete square, not for a single tree. Elevation is handled correctly, making it possible to seek cover behind slopes or dominate a battlefield by controlling high ground. Alternatively, reverse slope defence tactics can also be quite effective, as they were in real life.
- Airplanes cannot be controlled nor seen at all. Depending on the scenario description, airplanes will participate in the combat. All you will see is the fast moving shadow of the plane on the ground. Airplanes can be destroyed, however, (you will see tracers of machine gun and anti-aircraft fire streaming upwards) and in return shoot (with varying accuracy) with their guns, bombs and rockets.
- Indirect firing heavy artillery is mostly stationed off-screen and represented by a single artillery observer. If he has line of sight to a target, he can order very accurate shelling of the target area. However, target patterns are predictably oriented to the map edges. Barbarossa to Berlin introduced the idea of pre-registered barrages which can be called down immediately on the first turn of the game with no chance of error, representing pre-planned artillery missions rather than "on-call."
Combat Mission: Black Sea introduced the use of UAVs. Some models, notably those used by the US forces, can be used to identify targets beyond the operating unit's Line of Sight, allowing indirect fire support and CAS missions to be called in.
- Mortars and direct firing guns are presented in great detail.
- Tanks and all kinds of vehicles are modeled in great detail, with accurate researched values for speed, number of weapons, cannon range & angles, turret speed, and armor penetration angles / armor plates quality protecting different parts of a vehicle. Different ammunition types with different armor penetration values are present.
- Historical details like uniforms and availability of troop types and quality is very detailed and generally well researched with particular attention paid to German order of battle information. Any size unit from a platoon to a battalion may be used in the game, but specifics of weapons and manpower are non user-definable. However, extensive research into different troop and unit types gives a wide array of unit types. For example, while a player cannot define how many men or LMGs a squad of Germans will have, he can nonetheless select units from different branches (Luftwaffe, Waffen SS, Army, Volksgrenadiers) and types (Mechanized, Airborne, Infantry, Security, etc.), all of which have standardized but historically researched strengths and equipment.
