some debug and comments update

Author: liminchen

friction/time_integrator.py

@@ -27,7 +27,7 @@ def step_forward(x, e, v, m, l2, k, n, o, contact_area, mu, is_DBC, h, tol):
 
         # filter line search
         alpha = BarrierEnergy.init_step_size(x, n, o, p)  # avoid interpenetration and tunneling
-        while IP_val(x + alpha * p, e, x_tilde, m, l2, k, n, o, contact_area, (x - x_n) / h, mu_lambda, h) > E_last:
+        while IP_val(x + alpha * p, e, x_tilde, m, l2, k, n, o, contact_area, (x + alpha * p - x_n) / h, mu_lambda, h) > E_last:
             alpha /= 2
         print('step size =', alpha)
 

inv_free/simulator.py

@@ -1,4 +1,4 @@
-# Mass-Spring Solids Simulation
+# FEM Solids Simulation
 
 import numpy as np  # numpy for linear algebra
 import pygame       # pygame for visualization
@@ -23,7 +23,7 @@
 mu = 0.11        # friction coefficient of the slope
 
 # initialize simulation
-[x, e] = square_mesh.generate(side_len, n_seg)      # node positions and edge node indices
+[x, e] = square_mesh.generate(side_len, n_seg)      # node positions and triangle node indices
 x = np.append(x, [[0.0, side_len * 0.6]], axis=0)   # ceil origin (with normal [0.0, -1.0])
 v = np.array([[0.0, 0.0]] * len(x))                 # velocity
 m = [rho * side_len * side_len / ((n_seg + 1) * (n_seg + 1))] * len(x)  # calculate node mass evenly

inv_free/time_integrator.py

@@ -40,7 +40,7 @@ def step_forward(x, e, v, m, vol, IB, mu_lame, lam, n, o, contact_area, mu, is_D
 
         # filter line search
         alpha = min(BarrierEnergy.init_step_size(x, n, o, p), NeoHookeanEnergy.init_step_size(x, e, p))  # avoid interpenetration, tunneling, and inversion
-        while IP_val(x + alpha * p, e, x_tilde, m, vol, IB, mu_lame, lam, n, o, contact_area, (x - x_n) / h, mu_lambda, DBC, DBC_target, DBC_stiff, h) > E_last:
+        while IP_val(x + alpha * p, e, x_tilde, m, vol, IB, mu_lame, lam, n, o, contact_area, (x + alpha * p - x_n) / h, mu_lambda, DBC, DBC_target, DBC_stiff, h) > E_last:
             alpha /= 2
         print('step size =', alpha)
 

mov_dirichlet/time_integrator.py

@@ -40,7 +40,7 @@ def step_forward(x, e, v, m, l2, k, n, o, contact_area, mu, is_DBC, DBC, DBC_v,
 
         # filter line search
         alpha = BarrierEnergy.init_step_size(x, n, o, p)  # avoid interpenetration and tunneling
-        while IP_val(x + alpha * p, e, x_tilde, m, l2, k, n, o, contact_area, (x - x_n) / h, mu_lambda, DBC, DBC_target, DBC_stiff, h) > E_last:
+        while IP_val(x + alpha * p, e, x_tilde, m, l2, k, n, o, contact_area, (x + alpha * p - x_n) / h, mu_lambda, DBC, DBC_target, DBC_stiff, h) > E_last:
             alpha /= 2
         print('step size =', alpha)