from compas.geometry import Translation
from compas_cem.diagrams import TopologyDiagram
from compas_cem.elements import Node
from compas_cem.elements import TrailEdge
from compas_cem.elements import DeviationEdge
from compas_cem.loads import NodeLoad
from compas_cem.supports import NodeSupport
from compas_cem.equilibrium import static_equilibrium
from compas_cem.plotters import Plotter
# ------------------------------------------------------------------------------
# Instantiate a topology diagram
# ------------------------------------------------------------------------------
topology = TopologyDiagram()
# ------------------------------------------------------------------------------
# Add nodes
# ------------------------------------------------------------------------------
topology.add_node(Node(0, [0.0, 0.0, 0.0]))
topology.add_node(Node(1, [1.0, 0.0, 0.0]))
topology.add_node(Node(2, [2.5, 0.0, 0.0]))
topology.add_node(Node(3, [3.5, 0.0, 0.0]))
# ------------------------------------------------------------------------------
# Add edges
# ------------------------------------------------------------------------------
topology.add_edge(TrailEdge(0, 1, length=-1.5))
topology.add_edge(DeviationEdge(1, 2, force=-1.0))
topology.add_edge(TrailEdge(2, 3, length=-1.5))
# ------------------------------------------------------------------------------
# Add supports
# ------------------------------------------------------------------------------
topology.add_support(NodeSupport(0))
topology.add_support(NodeSupport(3))
# ------------------------------------------------------------------------------
# Add loads
# ------------------------------------------------------------------------------
topology.add_load(NodeLoad(1, [0.0, -1.0, 0.0]))
topology.add_load(NodeLoad(2, [0.0, -1.0, 0.0]))
# ------------------------------------------------------------------------------
# Build trails automatically
# ------------------------------------------------------------------------------
topology.build_trails()
# ------------------------------------------------------------------------------
# Compute a state of static equilibrium
# ------------------------------------------------------------------------------
form = static_equilibrium(topology, eta=1e-6, tmax=100, verbose=True)
# ------------------------------------------------------------------------------
# Plot results
# ------------------------------------------------------------------------------
plotter = Plotter()
# add topology diagram to scene
artist = plotter.add(topology, nodesize=0.2, show_nodetext=True, show_edgetext=True)
# add shifted form diagram to the scene
form = form.transformed(Translation.from_vector([0.0, -1.0, 0.0]))
plotter.add(form, nodesize=0.2, show_nodetext=True, show_edgetext=True)
# show plotter contents
plotter.zoom_extents()
plotter.show()
