Q: On the screenshots, which are available at the moment, the physics looks very impressive. Can you describe it in detail?
DM: It is really complicated to estimate the physics in ‘Faces of War’ only on the basis of screenshots. We see explosions, elements of vehicles flying apart, structures falling to ruins, dust, smoke, fire on static pictures… It is true that almost all special effects are designed based on laws of physics. Even particle systems work using these laws, the system allows us to indicate the air resistance, direction of wind and its strength, gravitation; we can create particles, which would bounce from the ground surface or other objects. However it is a minor part of physics system in ‘Faces of War’. These are only visible aspects. Others can be perceived only in the game, interacting with the gaming environment. This is the main purpose of physics system.
Q: Does it mean that player would deal with physics the whole gameplay through? Can you give some examples of unusual physics implementation, which were not available in RTS earlier?
DM: Yes, it is true. The player will encounter physics the whole gameplay through. Our game is not a simulator, but even vehicles behave according to laws of physics: a turn of tank on the place is accompanied with inertia; a flat tire of a car will make it give down on the specified point; if a car looses its wheel on the run, the car can turn down.
The ships in ‘Faces of War’ go according to the laws of physics as well. The vessels have compartments, which would be flooded, if there is a leak in the hull and the ship is lopsided. When the hull damages are critical, it would drown.
Speaking about unusual implementation of physics, the falling of structures and objects apart till they are completely destroyed is rather unusual in itself. Rather large building gets destroyed quite long, if you don’t explode the basement, you’ll need long time to bomb the structure piece by piece. It is designed to give the player the naturalness of the happening, for example a rock fence, which gave cover to a squad of soldiers from the rain of bullets fired out of several heavy machine-guns, would be destroyed at once even by a light tank. Larger objects are destroyed with higher complexity, and it can be too tough for a light tank.
With this level of refinement of the gaming world and its laws unusual ways of physics application in ‘Faces of War’ are born in the player’s head. It means, we didn’t apply here any patterns, in the opposite we supply the user with a wide and interesting space for experiments.
Q: How did you succeed to create a fully destroyable environment? What difficulties did the integration of physics bring to the development of ‘Faces of War’?
DM: The decision to create a fully destroyable environment was a step forward in relation to ‘Soldiers: Heroes of WWII’. All objects in the game could be destroyed even earlier, the players really liked it. We decided to preserve the tradition and made even more. We succeeded to make a refinement of destroying objects on the level, allowed by the terms of game development. It is obvious that this approach triggered the creation of complicated highly-refined models and textures. It influenced the development of destruction system and partially the physics. At the end we received a destruction system of various objects, which allow having their pieces broken off; you can destroy these objects completely or partially. All complex objects are calculated in the way that if their basements are destroyed, their upper parts are destroyed too.
It is a little bit improper to speak about the physics integration into the game engine. Like AI system the system of physics was a part of the GEM engine and was developed together with it and with the game. When we needed a new functionality of physics, we implemented changes, applied and tested it, considered them, made new changes and so on. Yes, we encountered difficulties, however not with the integration rather with the development. Frankly speaking there are a few game developers, who take upon the development of their own physics engine. It is a complicated thing and it is not always expedient.
Q: Does the physics really serve the gaming process? Can you give examples, how physics help to achieve strategic goals?
DM: The most simple and obvious application of physics in the game is the destruction of objects and obstacles. If the player faces the choice: to wait till the enemy shows up out of the cover or to destroy this cover himself, the player chooses often the latter. There are plenty of such examples. Shall the soldiers go under the cross-fire of machine-gunners from a house ambush or use abandoned field cannon and destroy the building to pieces? Shall a tank crew expose their machine to the free fire of cannons or hide the tank turret in the house ruins and turn it proudly from side to side threatening the enemy. Here we have both: tactics and strategy. Different situations suggest various solutions. In some situation the player will not be able to destroy everything around him, because he will have to save shells. Another time he’ll like to preserve the house to hide his soldiers inside in the future.
This option shows its features especially in the Multiplayer. Here you’ll have to fight against a “human” enemy, who would have his own plans for covers and obstacles. This all is just great fun and not only pure calculation. Watching the tank tracks grind the concrete chips of a destroyed structure is enough to get addicted to this process.
Q: Thanks to physics the battle fields will always be different depending on the player’s choice. If the environment can react in this way, is it possible to assume that we’ll never play on the same maps similarly?
DM: It is true. It depends on player’s decisions and actions. If he decides to go a new way, find another solution for a tactical task – yes, he will play differently. The player can play differently in Single-player mode as well (it is clear about the Multiplayer), the question is, if the player would like to play every time differently. We give the player such a chance. Sometimes we hint a little, but we never say it directly, how he can pass some place in the game. Otherwise the charm of challenge would disappear, the player will have no mystery to solve, no space for tests and experiments, and all become obvious. If the player is ready to take the challenge, it is up to him. He has got a map, troops; he can try, consider, try again, and play one more time. If the player doesn’t want to look for new solutions, no problem, there are more obvious ways to solve the issue. This is a challenge too. We let the players choose.
Q: What object types do have physical parameters?
DM: It is difficult to answer this question. In general all objects have corresponding physical parameters. In fact these are all objects, which can be found in the game. All of them can be exposed to physical effect and all of them have corresponding parameters of materials they consist of, i.e. mass and dimensions for calculation of collisions. The objects have additional parameters, which allow them to burn or get destroyed in a proper way. The full list of all additional parameters is enormous, it is processed by the separate system of the game engine, which is responsible for interactions.
Q: How are the damages inflicted from the point of view of power of various weapon types?
DM: Weapons have direct impact – a disruptive force and indirect impact – explosive blast (explosive shells, for example). Direct impact is applied directly to the target with the account of the hit angle (angle between the direction of shell flight and the surface), indirect is applied to all objects in the radius of the explosive blast action. Having enough power both can destroy or damage an object. The calculation of inflicted damages is carried out with the use of a special scheme; however this scheme is not built on hit-points. This system is unified for all game objects; however it is more refined and complicated for vehicles. Calculation of vehicle damages takes into account the damage of components, the damage from projectiles are calculated with account of armor rate of the place of shell hit.
If a shell or a bullet pierce an object through or ricochet from it, the shell or the bullet loose a part of its disruptive ability. The loss rate is calculated depending on the material used in the object and its thickness (exactly: the distance passed by the shell inside of the object). Unfortunately we can not give a detailed description, as the details of the damage system are kept in secret.
Q: How exact are the inflicted damages?
DM: On one hand the damages are rather authentic from the point of view of WWII history. On the other hand, the volume of inflicted damages is a question of good gameplay and balance, because we deal with a game first of all. We tried to achieve the latter, i.e. good and nice gameplay and correct balance without damaging the authentic system. Each weapon has its individual adjustments and parameters. The inflicted damage is customized individually. From this point of view the damages are very exact.
Q: The explosions look very impressive and refined. Are they calculated in advance (scripted) or will their trajectory change depending on the target? Does the equipment have gravity centers or the mass is applied to the whole model?
DM: There are a lot of various effects in the game; there are 30 types of explosions. These are shell explosions, effects from their hits to various materials (metal, wood, concrete, ground etc) and explosions of carious vehicle types. For calculation of shell hits with the vehicles the angle of shell collision with the armor is applied. The shell explosions produce explosion blast, which pushes objects and inflict damages (an explosive blast from a heavy shell scatter the humans all around).
A great number of effects was created not only for the purpose to make the picture more interesting, the effects are informative as well. By the effect you can tell, if the shell broke through the enemy armor or just scratched it.
Yes, the gravitation center of models and inertia tensor are calculated automatically by all models. As a model can consist of several parts, if one of them is broken off after a hit, all the parameters are calculated in a new way and the object still behaves physically correct.
Q: Would you like to say something to the community?
DM: I’d like to say to our fans that we’ll integrate improved chicken physics for sure.
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