Update app.py

app.py

@@ -47,7 +47,7 @@ def sample_info(sample_id_str, fieldn):
         nodes = nodes__
 
 
-    triangles = plaid_sample.get_elements()['TRI_3']
+    quads = plaid_sample.get_elements()['QUAD_4']
 
     # generate colormap
     if np.linalg.norm(field) > 0:
@@ -63,7 +63,7 @@ def sample_info(sample_id_str, fieldn):
         vertex_colors[:,2] = 0.15023281
 
     # generate mesh
-    trimesh = Trimesh(vertices = nodes, faces = triangles)
+    trimesh = Trimesh(vertices = nodes, faces = quads)
     trimesh.visual.vertex_colors = vertex_colors
     mesh = pyrender.Mesh.from_trimesh(trimesh, smooth=False)