Changed color scheme, avoid redrawing world if fig is shared.

rotorpy/learning/quadrotor_environments.py

@@ -1,6 +1,7 @@
 import numpy as np
 from scipy.spatial.transform import Rotation
 import matplotlib.pyplot as plt
+import matplotlib.colors as mcolors
 
 from enum import Enum
 from rotorpy.world import World
@@ -60,7 +61,8 @@ class QuadrotorEnv(gym.Env):
                  aero = True,                 # Whether or not aerodynamic wrenches are computed.
                  render_mode = "None",        # The rendering mode
                  render_fps = 30,             # The rendering frames per second. Lower this for faster visualization. 
-                 ax = None,
+                 fig = None,                  # Figure for rendering. Optional. 
+                 ax = None,                   # Axis for rendering. Optional. 
                 ):
         super(QuadrotorEnv, self).__init__()
 
@@ -151,13 +153,19 @@ class QuadrotorEnv(gym.Env):
             self.wind_profile = wind_profile
 
         if self.render_mode == '3D':
-            self.fig = plt.figure('Visualization')
-            # self.fig.clear()
-            self.ax = self.fig.add_subplot(projection='3d')
-            self.quad_obj = Quadrotor(self.ax, wind=True, color=np.random.rand(3))
+            if fig is None and ax is None:
+                self.fig = plt.figure('Visualization')
+                self.ax = self.fig.add_subplot(projection='3d')
+            else:
+                self.fig = fig
+                self.ax = ax
+            colors = list(mcolors.CSS4_COLORS)
+            self.quad_obj = Quadrotor(self.ax, wind=True, color=np.random.choice(colors))
             self.world_artists = None
             self.title_artist = self.ax.set_title('t = {}'.format(self.t))
 
+        self.rendering = False   # Bool for tracking when the renderer is actually rendering a frame. 
+
         return 
 
     def render(self):
@@ -402,14 +410,17 @@ class QuadrotorEnv(gym.Env):
 
     def _plot_quad(self):
 
-        if abs(self.t / (1/self.metadata['render_fps']) - round(self.t / (1/self.metadata['render_fps']))) > 1e-2:
+        if abs(self.t / (1/self.metadata['render_fps']) - round(self.t / (1/self.metadata['render_fps']))) > 5e-2:
+            self.rendering = False  # Set rendering bool to false.
             return
         
+        self.rendering = True # Set rendering bool to true. 
+
         plot_position = deepcopy(self.vehicle_state['x'])
         plot_rotation = Rotation.from_quat(self.vehicle_state['q']).as_matrix()
         plot_wind = deepcopy(self.vehicle_state['wind'])
 
-        if self.world_artists is None:
+        if self.world_artists is None and not ('x' in self.ax.get_xlabel()):
             self.world_artists = self.world.draw(self.ax)
             self.ax.plot(0, 0, 0, 'go')