Assignment 00 (Ungraded)

Goal: Familiarize yourself with compas and compas_timber by creating a manually constructed reciprocal frame node and transitioning to an automated, rule-based workflow using a custom class.

In class, we will go through the basic cases of setting up a timber model, direct joint assignments, and joint rules. This assignment bridges these concepts by tasking you with the development of a TimberModelCreator class that will contain methods to create timber models. This class will be extended and used throughout the course.

Exercise Steps

We have provided a Grasshopper file (a00_compas-timber_starting_point.ghx) that contains the starting components for each part of the assignment.

Part 1: Manual Construction

Construct a simple reciprocal frame (RF) node to understand the fundamental components of a COMPAS Timber model.

1. Open a00_compas-timber_starting_point.ghx in Rhino/Grasshopper.
2. Locate the group labeled Direct Joint Assignments.
3. Double-click the Python component to open the editor.
4. Complete the code inside to:
   • Creating beams from lines (Beam.from_centerline).
   • Manually placing joints (XLapJoint.create).

Part 2: Rule-Based Logic

Transition from manual assignments to rule-based automation.

1. Locate the group labeled Topology in the Grasshopper file.
2. Open the Python component and complete the code to use:
   • Topology Rules: Defining rules based on intersection types (X, T, or L shapes).
   • You can use the other two rule examples provided in the code right above.

Part 3: Automated Workflow with Classes

To prepare for more complex structures, you will implement/extend a helper class called TimberModelCreator in an external Python file, and then use it inside Grasshopper.

1. The Class:
   • Open a00_timber_model.py in VS Code.
   • Implement the missing methods: create_beams, add_topology_rules, and apply_rules.
2. The Script:
   • In Grasshopper, locate the group labeled COMPAS Timber Model - From Lines.
   • The Python component there is already set up to import your class.
   • Run the component (or press the button) to verify your class generates the model correctly.

Note: If you make changes to the .py file while Grasshopper is running, the code should update automatically thanks to a feature of COMPAS for auto reloading.

Expected Output

• A functional reciprocal frame unit consisting of three beams.
• Correct joinery at all beam intersections.
• A clean geometric output visualized in Rhino.

Resources

• COMPAS API Reference
• COMPAS Timber documentation