app.py

import streamlit as st
from streamlit_drawable_canvas import st_canvas
import networkx as nx
import matplotlib.pyplot as plt
from PyNite import FEModel3D
import numpy as np

def draw_truss_app():
    st.title("Truss Drawing & Analysis App")

    # Create a drawing canvas
    canvas_result = st_canvas(
        fill_color="rgba(255, 165, 0, 0.3)",
        stroke_width=2,
        stroke_color="#000000",
        background_color="#FFFFFF",
        height=400,
        width=600,
        drawing_mode="freedraw",
        key="canvas",
    )

    if st.button("Analyze Truss"):
        if canvas_result.json_data is not None:
            edges = process_canvas_data(canvas_result.json_data)
            G = create_graph(edges)
            plot_graph(G)
            analyze_truss(G)
        else:
            st.error("Please draw a truss before analyzing!")

def process_canvas_data(json_data):
    edges = []
    for obj in json_data["objects"]:
        if "path" in obj:
            path = obj["path"]
            for i in range(len(path) - 1):
                x1, y1 = path[i]
                x2, y2 = path[i + 1]
                edges.append(((x1, y1), (x2, y2)))
    return edges

def create_graph(edges):
    G = nx.Graph()
    for (x1, y1), (x2, y2) in edges:
        G.add_edge((x1, y1), (x2, y2))
    return G

def plot_graph(G):
    plt.figure(figsize=(6, 4))
    for edge in G.edges():
        x_values, y_values = zip(*edge)
        plt.plot(x_values, y_values, 'r-', linewidth=2)
    plt.gca().invert_yaxis()
    plt.show()
    st.pyplot(plt)

def analyze_truss(G):
    model = FEModel3D()
    for node in G.nodes():
        x, y = node
        model.add_node(str(node), x/100, y/100, 0)
    for edge in G.edges():
        n1, n2 = edge
        model.add_member(str(edge), str(n1), str(n2), "Steel", 0.01, 0.01)
    model.analyze()

    st.write("### Analysis Results:")
    for node in model.Nodes:
        st.write(f"Node {node}: DX = {model.Nodes[node].DX}, DY = {model.Nodes[node].DY}")

if __name__ == "__main__":
    draw_truss_app()