screen projection for all

Author: liminchen

dirichlet/GravityEnergy.py

@@ -1,6 +1,6 @@
 import numpy as np
 
-gravity = [0.0, 9.81]
+gravity = [0.0, -9.81]
 
 def val(x, m):
     sum = 0.0

dirichlet/simulator.py

@@ -13,7 +13,7 @@
 k = 1e3     # spring stiffness
 n_seg = 4   # num of segments per side of the square
 h = 0.02    # time step size in s
-DBC = [0, (n_seg + 1) * n_seg]  # fix the left and right top nodes
+DBC = [n_seg, (n_seg + 1) * (n_seg + 1) - 1]  # fix the left and right top nodes
 
 # initialize simulation
 [x, e] = square_mesh.generate(side_len, n_seg)  # node positions and edge node indices
@@ -29,10 +29,15 @@
 is_DBC = [False] * len(x)
 for i in DBC:
     is_DBC[i] = True
-
 # simulation with visualization
+resolution = np.array([900, 900])
+offset = resolution / 2
+scale = 200
+def screen_projection(x):
+    return [offset[0] + scale * x[0], resolution[1] - (offset[1] + scale * x[1])]
+
 time_step = 0
-screen = pygame.display.set_mode([900, 900])
+screen = pygame.display.set_mode(resolution)
 running = True
 while running:
     # run until the user asks to quit
@@ -45,9 +50,9 @@
     # fill the background and draw the square
     screen.fill((255, 255, 255))
     for eI in e:
-        pygame.draw.aaline(screen, (0, 0, 255), 450 + x[eI[0]] * 200, 450 + x[eI[1]] * 200)
+        pygame.draw.aaline(screen, (0, 0, 255), screen_projection(x[eI[0]]), screen_projection(x[eI[1]]))
     for xI in x:
-        pygame.draw.circle(screen, (0, 0, 255), 450 + xI * 200, 0.1 * side_len / n_seg * 200)
+        pygame.draw.circle(screen, (0, 0, 255), screen_projection(xI), 0.1 * side_len / n_seg * scale)
 
     pygame.display.flip()   # flip the display
 

mass_spring/simulator.py

@@ -30,8 +30,14 @@
     x[i][0] *= initial_stretch
 
 # simulation with visualization
+resolution = np.array([900, 900])
+offset = resolution / 2
+scale = 200
+def screen_projection(x):
+    return [offset[0] + scale * x[0], resolution[1] - (offset[1] + scale * x[1])]
+
 time_step = 0
-screen = pygame.display.set_mode([900, 900])
+screen = pygame.display.set_mode(resolution)
 running = True
 while running:
     # run until the user asks to quit
@@ -44,9 +50,9 @@
     # fill the background and draw the square
     screen.fill((255, 255, 255))
     for eI in e:
-        pygame.draw.aaline(screen, (0, 0, 255), 450 + x[eI[0]] * 200, 450 + x[eI[1]] * 200)
+        pygame.draw.aaline(screen, (0, 0, 255), screen_projection(x[eI[0]]), screen_projection(x[eI[1]]))
     for xI in x:
-        pygame.draw.circle(screen, (0, 0, 255), 450 + xI * 200, 0.1 * side_len / n_seg * 200)
+        pygame.draw.circle(screen, (0, 0, 255), screen_projection(xI), 0.1 * side_len / n_seg * scale)
 
     pygame.display.flip()   # flip the display