output obj for FEM

Author: liminchen

6_inv_free/simulator.py

@@ -50,6 +50,7 @@ def screen_projection(x):
     return [offset[0] + scale * x[0], resolution[1] - (offset[1] + scale * x[1])]
 
 time_step = 0
+square_mesh.write_to_file(time_step, x, e)
 screen = pygame.display.set_mode(resolution)
 running = True
 while running:
@@ -80,5 +81,6 @@ def screen_projection(x):
     [x, v] = time_integrator.step_forward(x, e, v, m, vol, IB, mu_lame, lam, ground_n, ground_o, contact_area, mu, is_DBC, DBC, DBC_v, DBC_limit, h, 1e-2)
     time_step += 1
     pygame.time.wait(int(h * 1000))
+    square_mesh.write_to_file(time_step, x, e)
 
 pygame.quit()

6_inv_free/square_mesh.py

@@ -1,4 +1,5 @@
 import numpy as np
+import os
 
 def generate(side_length, n_seg):
     # sample nodes uniformly on a square
@@ -20,4 +21,20 @@ def generate(side_length, n_seg):
                 e.append([i * (n_seg + 1) + j, (i + 1) * (n_seg + 1) + j, (i + 1) * (n_seg + 1) + j + 1])
                 e.append([i * (n_seg + 1) + j, (i + 1) * (n_seg + 1) + j + 1, i * (n_seg + 1) + j + 1])
 
-    return [x, e]
+    return [x, e]
+
+def write_to_file(frameNum, x, e):
+    # Check if 'output' directory exists; if not, create it
+    if not os.path.exists('output'):
+        os.makedirs('output')
+
+    # create obj file
+    filename = f"output/{frameNum}.obj"
+    with open(filename, 'w') as f:
+        # write vertex coordinates
+        for row in x:
+            f.write(f"v {float(row[0]):.6f} {float(row[1]):.6f} 0.0\n") 
+        # write vertex indices for each triangle
+        for row in e:
+            #NOTE: vertex indices start from 1 in obj file format
+            f.write(f"f {row[0] + 1} {row[1] + 1} {row[2] + 1}\n")

7_self_contact/simulator.py

@@ -53,6 +53,7 @@ def screen_projection(x):
     return [offset[0] + scale * x[0], resolution[1] - (offset[1] + scale * x[1])]
 
 time_step = 0
+square_mesh.write_to_file(time_step, x, e)
 screen = pygame.display.set_mode(resolution)
 running = True
 while running:
@@ -83,5 +84,6 @@ def screen_projection(x):
     [x, v] = time_integrator.step_forward(x, e, v, m, vol, IB, mu_lame, lam, ground_n, ground_o, bp, be, contact_area, mu, is_DBC, DBC, DBC_v, DBC_limit, h, 1e-2)
     time_step += 1
     pygame.time.wait(int(h * 1000))
+    square_mesh.write_to_file(time_step, x, e)
 
 pygame.quit()

7_self_contact/square_mesh.py

@@ -1,4 +1,5 @@
 import numpy as np
+import os
 
 def generate(side_length, n_seg):
     # sample nodes uniformly on a square
@@ -39,4 +40,20 @@ def find_boundary(e):
             be.append([eI[0], eI[1]])
             bp_set.add(eI[0])
             bp_set.add(eI[1])
-    return [list(bp_set), be]
+    return [list(bp_set), be]
+
+def write_to_file(frameNum, x, e):
+    # Check if 'output' directory exists; if not, create it
+    if not os.path.exists('output'):
+        os.makedirs('output')
+
+    # create obj file
+    filename = f"output/{frameNum}.obj"
+    with open(filename, 'w') as f:
+        # write vertex coordinates
+        for row in x:
+            f.write(f"v {float(row[0]):.6f} {float(row[1]):.6f} 0.0\n") 
+        # write vertex indices for each triangle
+        for row in e:
+            #NOTE: vertex indices start from 1 in obj file format
+            f.write(f"f {row[0] + 1} {row[1] + 1} {row[2] + 1}\n")

8_self_friction/simulator.py

@@ -53,6 +53,7 @@ def screen_projection(x):
     return [offset[0] + scale * x[0], resolution[1] - (offset[1] + scale * x[1])]
 
 time_step = 0
+square_mesh.write_to_file(time_step, x, e)
 screen = pygame.display.set_mode(resolution)
 running = True
 while running:
@@ -83,5 +84,6 @@ def screen_projection(x):
     [x, v] = time_integrator.step_forward(x, e, v, m, vol, IB, mu_lame, lam, ground_n, ground_o, bp, be, contact_area, mu, is_DBC, DBC, DBC_v, DBC_limit, h, 1e-2)
     time_step += 1
     pygame.time.wait(int(h * 1000))
+    square_mesh.write_to_file(time_step, x, e)
 
 pygame.quit()

8_self_friction/square_mesh.py

@@ -1,4 +1,5 @@
 import numpy as np
+import os
 
 def generate(side_length, n_seg):
     # sample nodes uniformly on a square
@@ -39,4 +40,20 @@ def find_boundary(e):
             be.append([eI[0], eI[1]])
             bp_set.add(eI[0])
             bp_set.add(eI[1])
-    return [list(bp_set), be]
+    return [list(bp_set), be]
+
+def write_to_file(frameNum, x, e):
+    # Check if 'output' directory exists; if not, create it
+    if not os.path.exists('output'):
+        os.makedirs('output')
+
+    # create obj file
+    filename = f"output/{frameNum}.obj"
+    with open(filename, 'w') as f:
+        # write vertex coordinates
+        for row in x:
+            f.write(f"v {float(row[0]):.6f} {float(row[1]):.6f} 0.0\n") 
+        # write vertex indices for each triangle
+        for row in e:
+            #NOTE: vertex indices start from 1 in obj file format
+            f.write(f"f {row[0] + 1} {row[1] + 1} {row[2] + 1}\n")