Added Step Back and Restart feature

znvis/particle/particle.py

@@ -51,6 +51,10 @@ class Particle:
             Director tensor of the shape (n_confs, n_particles, n_dims)
     mesh_list : list
             A list of mesh objects, one for each time step.
+    static : bool (default=False)
+            If true, only render the mesh once at initialization. Be careful
+            as this changes the shape of the required position and director 
+            to (n_particles, n_dims) 
     smoothing : bool (default=False)
             If true, apply smoothing to each mesh object as it is rendered.
             This will slow down the initial construction of the mesh objects
@@ -64,7 +68,7 @@ class Particle:
     force: np.ndarray = None
     director: np.ndarray = None
     mesh_list: typing.List[Mesh] = None
-
+    static: bool = False
     smoothing: bool = False
 
     def _create_mesh(self, position, director):
@@ -105,13 +109,21 @@ def construct_mesh_list(self):
         """
         self.mesh_list = []
         try:
-            # n_particles = int(self.position.shape[1])
-            n_time_steps = int(len(self.position))
+            if not self.static: 
+                n_particles = int(self.position.shape[1])
+                n_time_steps = int(self.position.shape[0])
+            else:
+                n_particles = int(self.position.shape[0])
+                n_time_steps = 1
+                self.position = self.position[np.newaxis, :, :]
+                if self.director is not None:
+                    self.director = self.director[np.newaxis, :, :]
+
         except ValueError:
             raise ValueError("There is no data for these particles.")
 
         for i in track(range(n_time_steps), description=f"Building {self.name} Mesh"):
-            for j in range(np.shape(self.position[i])[0]):
+            for j in range(n_particles):
                 if j == 0:
                     if self.director is not None:
                         mesh = self._create_mesh(

znvis/particle/vector_field.py

@@ -47,6 +47,10 @@ class VectorField:
             Direction tensor of the shape (n_steps, n_vectors, n_dims)
     mesh_list : list
             A list of mesh objects, one for each time step.
+    static : bool (default=False)
+            If true, only render the mesh once at initialization. Be careful
+            as this changes the shape of the required position and direction 
+            to (n_particles, n_dims) 
     smoothing : bool (default=False)
             If true, apply smoothing to each mesh object as it is rendered.
             This will slow down the initial construction of the mesh objects
@@ -58,7 +62,7 @@ class VectorField:
     position: np.ndarray = None
     direction: np.ndarray = None
     mesh_list: typing.List[Arrow] = None
-
+    static: bool = False
     smoothing: bool = False
 
     def _create_mesh(self, position: np.ndarray, direction: np.ndarray):
@@ -97,15 +101,28 @@ def construct_mesh_list(self):
         """
         self.mesh_list = []
         try:
-            n_particles = int(self.position.shape[1])
-            n_time_steps = int(self.position.shape[0])
+            if not self.static: 
+                n_particles = int(self.position.shape[1])
+                n_time_steps = int(self.position.shape[0])
+            else:
+                n_particles = int(self.position.shape[0])
+                n_time_steps = 1
+                self.position = self.position[np.newaxis, :, :]
+                self.direction = self.direction[np.newaxis, :, :]
+
         except ValueError:
             raise ValueError("There is no data for this vector field.")
 
+        new_mesh = True
+
         for i in track(range(n_time_steps), description=f"Building {self.name} Mesh"):
             for j in range(n_particles):
-                if j == 0:
-                    mesh = self._create_mesh(self.position[i][j], self.direction[i][j])
-                else:
-                    mesh += self._create_mesh(self.position[i][j], self.direction[i][j])
+                if np.max(self.direction[i][j]) > 0: # ignore vectors with length zero
+                    if new_mesh is False:
+                        mesh += self._create_mesh(self.position[i][j], self.direction[i][j])
+                    else:
+                        mesh = self._create_mesh(self.position[i][j], self.direction[i][j])
+                        new_mesh = False
+            new_mesh = True
+
             self.mesh_list.append(mesh)