Survival : Escape from Observers
This scenario is similar to Avoid Reaver, but much more difficult.
It is a scenario in which an agent (Zerg Scourge) that started at the bottom of the map should move to the top of the map to avoid more than 100 protoss observers randomly moving in the entire area of the map.
The episode ends when the agent collides with protoss observers or arrives at the top of the map.
This map is relatively difficult as following reasons.
- larger size of map. : The size of the map is 128 X 128 tiles, much larger than 10 x 10 of the river cover.
- more obstacles. : There are three obstacles to river cover, but this map should reach the top by avoiding more than 100 observers.
- terminate condition of the episode : Unlike River Avoidance, when an agent hits an obstacle (observer), the episode ends.
- randomness : There is randomness due to the nature of StarCraft map, so that there is a slight chance an episode won’t end even if the agent collides with observers.
Action Space
In this scenario, only thing to decide is where to move. We provide three types of action space which has different output values. To conquer this scenario with high probability of success, you may need to use the continuous action space rather than the discrete action space.
| Action Type | Type | Output | Description |
|---|---|---|---|
| 0 | Discrete | one integer between 0 ~ action size | Output number means the moving direction. 0 means 3 o’clock. The total number of action spaces is defined as 360 / (move-dist). The last number of action means stop moving |
| 1 | Continuous | x, y, action number | ● X, Y : 2D coordinates, ● the action number 0 : move, 1 : attack move |
| 2 | Continuous | theta, radian, action number | ● theta : the angle started from 3 0’clock ● radian : distance to move toward specific direction ● action number 0 : move, 1 : attack move |
Observation
To reach the goal without collision, the agent must know the information of close enemies such as position, velocity, acceleration, etc. But some information like hit points, shield, energy, something has to do with combat may not necessary in this scenario. Therefore, pre-processing of the raw observation into meaningful input features is essential.
- Base Information of unit type
| Observation name | Description | Type |
|---|---|---|
| acceleration | The unit’s accelation amount | int32 |
| armor | The amount of armor the unit type has | int32 |
| cooldown_max | The amount of base cooldown applied to the unit after an attack | int32 |
| damage_amount | The base amount of damage that this weapon can deal per attack | int32 |
| damage_factor | The intended number of missiles/attacks that are used. This is used to multiply with the damage amount to obtain the full amount of damage for an attack. | int32 |
| energy_max | The maximum amount of energy for this unit type | int32 |
| hp_max | The maximum amount of hit points for this unit type | int32 |
| seek_range | The range at which this unit type will start targeting enemy units | int32 |
| shield_max | The maximum amount of shield points for this unit type | int32 |
| sight_range | The sight range of this unit type | int32 |
| top_speed | The unit type’s top movement speed with no upgrades | double |
| weapon_range | The maximum attack range of the weapon, measured in pixels | int32 |
- Current informaiton of all units in game
| Observation name | Description | Type |
|---|---|---|
| unit_type | The type of unit | string |
| hp | The current amount of hit points for this unit | int32 |
| shield | The current amount of shield points for this unit | int32 |
| energy | The current amount of energy points for this unit | int32 |
| cooldown | The current amount of cooldown for this unit | int32 |
| pos_x | The X coordinates for current position of this unit. The position is roughly the center if the unit | int32 |
| pos_y | The Y coordinates for current position of this unit. The position is roughly the center if the unit | int32 |
| velocity_x | The X component of the unit’s velocity, measured in pixels per frame | double |
| velocity_y | The Y component of the unit’s velocity, measured in pixels per frame | double |
| angle | The unit’s facing direction in radians | double |
| accelerating | True, if the current unit is accelerating. | bool |
| braking | True, if the current unit is slowing down to come to a stop | bool |
| attacking | True, if this unit is currently attacking something | bool |
| is_attack_frame | True, if this unit is currently playing an attack animation | bool |
Reward
In the case of that scenario, when the agent reaches the top of the map or collides with an observer the episode ends.
What is unusual thing in the scenario is that there is the safe area where the agent never die even if it collides with observers.
So if you don’t reshape the reward properly, you may see the scourge trying to stay at the safe area to avoid dying.
- +5 : when agent reaches the goal.
- -5 : when agent collides with enemy
- +0.5 : others
Environment configuration
You should know those parameters when you create the environment.
from saida_gym.starcraft.avoidObserver import AvoidObserver
env = AvoidObserver(version=0, action_type=2, frames_per_step=6, verbose=0)
- version (integer): version of the map. The difficulty is various according to the version. (default = 0)
- action_type (integer) : 0 is the discrete action space, 1 and 2 are the continuous action space.
- frames_per_step (integer): determine how many frames will be skipped in one step of action.
- move_angle (integer) : in case of discrete action type, this value determines the total number of action spaces. 360 degrees divided by ‘move_angle’ will be the number of action spaces.
For example, if ‘move_angle’ is 30, 360/30 = 12 will be the number of action spaces. That means this value should be divisor of 360. - move_dist (integer): determine how far the agent will move in one step. unit = tile size (1 tile = 32px)
- verbose (integer): log level
- bot_runner (bool): None only if you don’t want to execute starcraft bot automatically.
- no_gui (bool): True if you want to render the game.(default : False)
- local_speed (integer): the play speed of starcraft in game (default : 0)
- auto_kill (bool): True if you want to kill ongoing starcraft process. (default : True)
- random_seed (integer): random seed value which determines randomness of starcraft