WIP materialization Mesh from Thrust Diagram.

Author: petrasvestartas

gitbook/.gitbook/assets/materialization_thrust_diagram.png

@@ -10,16 +10,15 @@ The aim of this tutorial is to convert a RhinoVault session (a JSON file with a
 
 ## Pattern from RhinoVault Session
 
-Before you start create a folder on your computer where you will store the `rhinovault_session.json` file as well as python example files. Then open Rhino Script Editor by command `ScriptEditor`. And copy-paste the code below that extracts the mesh pattern from the session file.
+<figure><img src="../.gitbook/assets/materialization_pattern.gif" alt=""><figcaption></figcaption></figure>
+
+Before you start create a folder on your computer where you will store the `rhinovault_session.json` file as well as python example files. Then open Rhino Script Editor by command `ScriptEditor`. Add a new python file by clicking on the plus sign named `000.pattern.py`. Then copy-paste the code below that extracts the mesh pattern from the session file.
 
 The session file employs the compas.scene data structure for storing: Pattern, FormDiagram, ThrustDiagram, and ForceDiagram. It also stores general settings for drawing and thrust-network analysis. We will use two attributes: Pattern and ThrustDiagram for mesh transformation into solid blocks. The scene also helps to visualize COMPAS items (geometry & data structures).
 
 The first three comments are specific to Python in Rhino, indicating: a) `python3` specifies the language used, b) the code is written in the `brg-csd` environment, and c) `compas_rv` is a library requirement that must be installable from the Python Package Index (PyPI).
 
 
-<figure><img src="../.gitbook/assets/materialization_pattern.gif" alt=""><figcaption></figcaption></figure>
-
-
 ```python
 #! python3
 # venv: brg-csd
@@ -46,6 +45,111 @@ scene.add(rv_scene.find_by_name("Pattern").mesh)
 scene.draw()
 ```
 
-## RhinoVault Session - ThrustDiagram
+## Mesh from Thrust Diagram
+
+<figure><img src="../.gitbook/assets/materialization_thrust_diagram.png" alt=""><figcaption></figcaption></figure>
+
+Let's create file called `001_thrust_diagram.py` in the script editor. The thrust diagram's mesh attribute is used as the base mesh for materialization. We need to delete mesh faces with the attribute `_is_loaded==False`, marked in red. After deletion, we will split the list of boundary vertices by support vertices and store them in the `borders` attribute. We will also store support points in the `supports` attribute. Be aware that the script does not handle multiple boundaries, and you may need to make your own modifications for other cases if the mesh topology is different. Finally, the mesh is serialized into JSON file called `001_mesh.json`.
+
+In this step we will extract thrust-diagram.
+
+```python
+#! python3
+# venv: brg-csd
+# r: compas_rv
+
+import pathlib
+
+import compas
+from compas.datastructures import Mesh
+from compas.scene import Scene
+from compas_tna.diagrams import FormDiagram
+from compas import json_dump
+from compas.itertools import pairwise
+
+
+def break_boundary(mesh: Mesh, breakpoints: list[int]) -> tuple[list[list[int]], list[int]]:
+
+    # Get the list of vertices on the boundary (first boundary from the mesh)
+    boundary: list[int] = mesh.vertices_on_boundaries()[0]
+    
+    # If the first and last vertices in the boundary are the same, remove the last vertex (close loop)
+    if boundary[0] == boundary[-1]:
+        del boundary[-1]
+
+    # Sort the breakpoints based on their index in the boundary
+    breakpoints = sorted(breakpoints, key=lambda s: boundary.index(s))
+
+    # Find the starting point in the boundary for the first breakpoint
+    start = boundary.index(breakpoints[0])
+    
+    # Rearrange the boundary to start from the first breakpoint
+    boundary = boundary[start:] + boundary[:start]
+
+    # Iterate over pairs of breakpoints and create sub-boundaries from the main boundary
+    borders = []
+    
+    for a, b in pairwise(breakpoints):
+        start = boundary.index(a)  # Find index of the first breakpoint in the boundary
+        end = boundary.index(b)    # Find index of the second breakpoint in the boundary
+        borders.append(boundary[start : end + 1])  # Add the sub-boundary from start to end
+
+    # Add the last segment from the last breakpoint to the first one to close the loop
+    borders.append(boundary[end:] + boundary[:1])
+
+    # Return the sub-boundaries and the breakpoints
+    return borders, breakpoints
+
+
+# =============================================================================
+# Load data
+# =============================================================================
+
+IFILE = pathlib.Path(__file__).parent / "rhinovault_session.json"
+
+rv_session = compas.json_load(IFILE)
+rv_scene: Scene = rv_session["scene"]
+
+thrustobject = rv_scene.find_by_name("ThrustDiagram")
+thrustdiagram: FormDiagram = thrustobject.mesh
+
+# =============================================================================
+# Mesh
+#
+# - make a copy of the thrustdiagram
+# - remove the "TNA" faces cooresponding to boundary openings
+# - compute the average edge length for remeshing
+# =============================================================================
+
+mesh: Mesh = thrustdiagram.copy(cls=Mesh)
+
+# for face in list(mesh.faces_where(_is_loaded=False)):
+#     mesh.delete_face(face)
+
+# =============================================================================
+# Mesh: Borders
+# =============================================================================
+
+supports = list(mesh.vertices_where(is_support=True))
+borders, supports = break_boundary(mesh, supports)
+print(borders)
+print(supports)
+
+mesh.attributes["supports"] = supports
+mesh.attributes["borders"] = borders
+
+# =============================================================================
+# Serialize
+# =============================================================================
 
-In this step we will extract thrust-diagram.
+json_dump(mesh, pathlib.Path(__file__).parent / "001_mesh.json")
+
+# =============================================================================
+# Visualisation
+# =============================================================================
+
+scene = Scene()
+# scene.clear_context()
+scene.add(mesh)
+scene.draw()
+```