Tiger-Deer
This environment is part of the magent environments. Please read that page first for general information.
| Name | Value |
|---|---|
| Actions | Discrete |
| Agents | 121 |
| Parallel API | Yes |
| Manual Control | No |
| Action Shape | (5),(9) |
| Action Values | Discrete(5),(9) |
| Observation Shape | (3,3,21), (9,9,25) |
| Observation Values | [0,2] |
| Import | pettingzoo.magent import tiger_deer_v3 |
| Agents | agents= [ deer_[0-100], tiger_[0-19] ] |
Agent Environment Cycle
Tiger-Deer
In tiger-deer, there are a number of tigers who are only rewarded for teaming up to take down the deer (two tigers must attack a deer in the same step to receive reward). If they do not eat the deer, they will slowly lose 0.1 HP each turn until they die. If they do eat the deer they regain 8 health (they have 10 health to start). At the same time, the deer are trying to avoid getting attacked. Deer start with 5 HP, lose 1 HP when attacked, and regain 0.1 HP each turn. Deer should run from tigers and tigers should form small teams to take down deer.
Action Space
Key: move_N means N separate actions, one to move to each of the N nearest squares on the grid.
Tiger action space: [do_nothing, move_4, attack_4]
Deer action space: [do_nothing, move_4]
Reward
Tiger’s reward scheme is:
- 1 reward for attacking a deer alongside another tiger
Deer’s reward scheme is:
- -1 reward for dying
- -0.1 for being attacked
Observation space
The observation space is a 3x3 map with 21 channels for deer and 9x9 map with 25 channels for tigers, which are (in order):
| name | number of channels |
|---|---|
| obstacle/off the map | 1 |
| my_team_presence | 1 |
| my_team_hp | 1 |
| other_team_presence | 1 |
| other_team_hp | 1 |
| binary_agent_id | 10 |
| one_hot_action | 5 Deer/9 Tiger |
| last_reward | 1 |
| agent_position | 2 |
Arguments
tiger_deer_v3.env(map_size=45, minimap_mode=False, tiger_step_recover=-0.1, deer_attacked=-0.1, max_cycles=500)
map_size: Sets dimensions of the (square) map. Increasing the size increases the number of agents. Minimum size is 10.
minimap_mode: Turns on global minimap observations. These observations include your and your opponents piece densities binned over the 2d grid of the observation space. Also includes your agent_position, the absolute position on the map (rescaled from 0 to 1).
tiger_step_recover: Amount of health a tiger gains/loses per turn (tigers have health 10 and get health 8 from killing a deer)
deer_attacked: Reward a deer gets for being attacked
max_cycles: number of frames (a step for each agent) until game terminates