lerobot/lerobot/common/envs/pusht/pusht_env.py

379 lines
13 KiB
Python

import collections
import cv2
import gymnasium as gym
import numpy as np
import pygame
import pymunk
import pymunk.pygame_util
import shapely.geometry as sg
import skimage.transform as st
from gymnasium import spaces
from pymunk.vec2d import Vec2d
from lerobot.common.envs.pusht.pymunk_override import DrawOptions
def pymunk_to_shapely(body, shapes):
geoms = []
for shape in shapes:
if isinstance(shape, pymunk.shapes.Poly):
verts = [body.local_to_world(v) for v in shape.get_vertices()]
verts += [verts[0]]
geoms.append(sg.Polygon(verts))
else:
raise RuntimeError(f"Unsupported shape type {type(shape)}")
geom = sg.MultiPolygon(geoms)
return geom
class PushTEnv(gym.Env):
metadata = {"render.modes": ["human", "rgb_array"], "video.frames_per_second": 10}
reward_range = (0.0, 1.0)
def __init__(
self,
legacy=True, # compatibility with original
block_cog=None,
damping=None,
render_action=True,
render_size=96,
reset_to_state=None,
):
self._seed = None
self.seed()
self.window_size = ws = 512 # The size of the PyGame window
self.render_size = render_size
self.sim_hz = 100
# Local controller params.
self.k_p, self.k_v = 100, 20 # PD control.z
self.control_hz = self.metadata["video.frames_per_second"]
# legcay set_state for data compatibility
self.legacy = legacy
# agent_pos, block_pos, block_angle
self.observation_space = spaces.Box(
low=np.array([0, 0, 0, 0, 0], dtype=np.float64),
high=np.array([ws, ws, ws, ws, np.pi * 2], dtype=np.float64),
shape=(5,),
dtype=np.float64,
)
# positional goal for agent
self.action_space = spaces.Box(
low=np.array([0, 0], dtype=np.float64),
high=np.array([ws, ws], dtype=np.float64),
shape=(2,),
dtype=np.float64,
)
self.block_cog = block_cog
self.damping = damping
self.render_action = render_action
"""
If human-rendering is used, `self.window` will be a reference
to the window that we draw to. `self.clock` will be a clock that is used
to ensure that the environment is rendered at the correct framerate in
human-mode. They will remain `None` until human-mode is used for the
first time.
"""
self.window = None
self.clock = None
self.screen = None
self.space = None
self.teleop = None
self.render_buffer = None
self.latest_action = None
self.reset_to_state = reset_to_state
def reset(self):
seed = self._seed
self._setup()
if self.block_cog is not None:
self.block.center_of_gravity = self.block_cog
if self.damping is not None:
self.space.damping = self.damping
# use legacy RandomState for compatibility
state = self.reset_to_state
if state is None:
rs = np.random.RandomState(seed=seed)
state = np.array(
[
rs.randint(50, 450),
rs.randint(50, 450),
rs.randint(100, 400),
rs.randint(100, 400),
rs.randn() * 2 * np.pi - np.pi,
]
)
self._set_state(state)
observation = self._get_obs()
return observation
def step(self, action):
dt = 1.0 / self.sim_hz
self.n_contact_points = 0
n_steps = self.sim_hz // self.control_hz
if action is not None:
self.latest_action = action
for _ in range(n_steps):
# Step PD control.
# self.agent.velocity = self.k_p * (act - self.agent.position) # P control works too.
acceleration = self.k_p * (action - self.agent.position) + self.k_v * (
Vec2d(0, 0) - self.agent.velocity
)
self.agent.velocity += acceleration * dt
# Step physics.
self.space.step(dt)
# compute reward
goal_body = self._get_goal_pose_body(self.goal_pose)
goal_geom = pymunk_to_shapely(goal_body, self.block.shapes)
block_geom = pymunk_to_shapely(self.block, self.block.shapes)
intersection_area = goal_geom.intersection(block_geom).area
goal_area = goal_geom.area
coverage = intersection_area / goal_area
reward = np.clip(coverage / self.success_threshold, 0, 1)
done = coverage > self.success_threshold
observation = self._get_obs()
info = self._get_info()
return observation, reward, done, info
def render(self, mode):
return self._render_frame(mode)
def teleop_agent(self):
TeleopAgent = collections.namedtuple("TeleopAgent", ["act"])
def act(obs):
act = None
mouse_position = pymunk.pygame_util.from_pygame(Vec2d(*pygame.mouse.get_pos()), self.screen)
if self.teleop or (mouse_position - self.agent.position).length < 30:
self.teleop = True
act = mouse_position
return act
return TeleopAgent(act)
def _get_obs(self):
obs = np.array(
tuple(self.agent.position) + tuple(self.block.position) + (self.block.angle % (2 * np.pi),)
)
return obs
def _get_goal_pose_body(self, pose):
mass = 1
inertia = pymunk.moment_for_box(mass, (50, 100))
body = pymunk.Body(mass, inertia)
# preserving the legacy assignment order for compatibility
# the order here doesn't matter somehow, maybe because CoM is aligned with body origin
body.position = pose[:2].tolist()
body.angle = pose[2]
return body
def _get_info(self):
n_steps = self.sim_hz // self.control_hz
n_contact_points_per_step = int(np.ceil(self.n_contact_points / n_steps))
info = {
"pos_agent": np.array(self.agent.position),
"vel_agent": np.array(self.agent.velocity),
"block_pose": np.array(list(self.block.position) + [self.block.angle]),
"goal_pose": self.goal_pose,
"n_contacts": n_contact_points_per_step,
}
return info
def _render_frame(self, mode):
if self.window is None and mode == "human":
pygame.init()
pygame.display.init()
self.window = pygame.display.set_mode((self.window_size, self.window_size))
if self.clock is None and mode == "human":
self.clock = pygame.time.Clock()
canvas = pygame.Surface((self.window_size, self.window_size))
canvas.fill((255, 255, 255))
self.screen = canvas
draw_options = DrawOptions(canvas)
# Draw goal pose.
goal_body = self._get_goal_pose_body(self.goal_pose)
for shape in self.block.shapes:
goal_points = [
pymunk.pygame_util.to_pygame(goal_body.local_to_world(v), draw_options.surface)
for v in shape.get_vertices()
]
goal_points += [goal_points[0]]
pygame.draw.polygon(canvas, self.goal_color, goal_points)
# Draw agent and block.
self.space.debug_draw(draw_options)
if mode == "human":
# The following line copies our drawings from `canvas` to the visible window
self.window.blit(canvas, canvas.get_rect())
pygame.event.pump()
pygame.display.update()
# the clock is already ticked during in step for "human"
img = np.transpose(np.array(pygame.surfarray.pixels3d(canvas)), axes=(1, 0, 2))
img = cv2.resize(img, (self.render_size, self.render_size))
if self.render_action and self.latest_action is not None:
action = np.array(self.latest_action)
coord = (action / 512 * 96).astype(np.int32)
marker_size = int(8 / 96 * self.render_size)
thickness = int(1 / 96 * self.render_size)
cv2.drawMarker(
img,
coord,
color=(255, 0, 0),
markerType=cv2.MARKER_CROSS,
markerSize=marker_size,
thickness=thickness,
)
return img
def close(self):
if self.window is not None:
pygame.display.quit()
pygame.quit()
def seed(self, seed=None):
if seed is None:
seed = np.random.randint(0, 25536)
self._seed = seed
self.np_random = np.random.default_rng(seed)
def _handle_collision(self, arbiter, space, data):
self.n_contact_points += len(arbiter.contact_point_set.points)
def _set_state(self, state):
if isinstance(state, np.ndarray):
state = state.tolist()
pos_agent = state[:2]
pos_block = state[2:4]
rot_block = state[4]
self.agent.position = pos_agent
# setting angle rotates with respect to center of mass
# therefore will modify the geometric position
# if not the same as CoM
# therefore should be modified first.
if self.legacy:
# for compatibility with legacy data
self.block.position = pos_block
self.block.angle = rot_block
else:
self.block.angle = rot_block
self.block.position = pos_block
# Run physics to take effect
self.space.step(1.0 / self.sim_hz)
def _set_state_local(self, state_local):
agent_pos_local = state_local[:2]
block_pose_local = state_local[2:]
tf_img_obj = st.AffineTransform(translation=self.goal_pose[:2], rotation=self.goal_pose[2])
tf_obj_new = st.AffineTransform(translation=block_pose_local[:2], rotation=block_pose_local[2])
tf_img_new = st.AffineTransform(matrix=tf_img_obj.params @ tf_obj_new.params)
agent_pos_new = tf_img_new(agent_pos_local)
new_state = np.array(list(agent_pos_new[0]) + list(tf_img_new.translation) + [tf_img_new.rotation])
self._set_state(new_state)
return new_state
def _setup(self):
self.space = pymunk.Space()
self.space.gravity = 0, 0
self.space.damping = 0
self.teleop = False
self.render_buffer = []
# Add walls.
walls = [
self._add_segment((5, 506), (5, 5), 2),
self._add_segment((5, 5), (506, 5), 2),
self._add_segment((506, 5), (506, 506), 2),
self._add_segment((5, 506), (506, 506), 2),
]
self.space.add(*walls)
# Add agent, block, and goal zone.
self.agent = self.add_circle((256, 400), 15)
self.block = self.add_tee((256, 300), 0)
self.goal_color = pygame.Color("LightGreen")
self.goal_pose = np.array([256, 256, np.pi / 4]) # x, y, theta (in radians)
# Add collision handling
self.collision_handeler = self.space.add_collision_handler(0, 0)
self.collision_handeler.post_solve = self._handle_collision
self.n_contact_points = 0
self.max_score = 50 * 100
self.success_threshold = 0.95 # 95% coverage.
def _add_segment(self, a, b, radius):
shape = pymunk.Segment(self.space.static_body, a, b, radius)
shape.color = pygame.Color("LightGray") # https://htmlcolorcodes.com/color-names
return shape
def add_circle(self, position, radius):
body = pymunk.Body(body_type=pymunk.Body.KINEMATIC)
body.position = position
body.friction = 1
shape = pymunk.Circle(body, radius)
shape.color = pygame.Color("RoyalBlue")
self.space.add(body, shape)
return body
def add_box(self, position, height, width):
mass = 1
inertia = pymunk.moment_for_box(mass, (height, width))
body = pymunk.Body(mass, inertia)
body.position = position
shape = pymunk.Poly.create_box(body, (height, width))
shape.color = pygame.Color("LightSlateGray")
self.space.add(body, shape)
return body
def add_tee(self, position, angle, scale=30, color="LightSlateGray", mask=None):
if mask is None:
mask = pymunk.ShapeFilter.ALL_MASKS()
mass = 1
length = 4
vertices1 = [
(-length * scale / 2, scale),
(length * scale / 2, scale),
(length * scale / 2, 0),
(-length * scale / 2, 0),
]
inertia1 = pymunk.moment_for_poly(mass, vertices=vertices1)
vertices2 = [
(-scale / 2, scale),
(-scale / 2, length * scale),
(scale / 2, length * scale),
(scale / 2, scale),
]
inertia2 = pymunk.moment_for_poly(mass, vertices=vertices1)
body = pymunk.Body(mass, inertia1 + inertia2)
shape1 = pymunk.Poly(body, vertices1)
shape2 = pymunk.Poly(body, vertices2)
shape1.color = pygame.Color(color)
shape2.color = pygame.Color(color)
shape1.filter = pymunk.ShapeFilter(mask=mask)
shape2.filter = pymunk.ShapeFilter(mask=mask)
body.center_of_gravity = (shape1.center_of_gravity + shape2.center_of_gravity) / 2
body.position = position
body.angle = angle
body.friction = 1
self.space.add(body, shape1, shape2)
return body