FCS Scripting Language - Knowledge Base for LLM Agents

This folder contains documentation and examples for training AI coding agents (Golem) to write FemCAD Script (FCS) code.

Purpose

Enable LLM agents to:

1. Understand and write FCS scripts without access to interpreter source code
2. Generate valid geometry, mesh, and analysis definitions
3. Work with the FLI command-line interface
4. Create structural engineering models programmatically

Documentation Files

Example Projects

Learning Path

1. Start with basics: Read 01-LANGUAGE-BASICS.md for syntax and types
2. Learn geometry: Read 02-GEOMETRY-PRIMITIVES.md for creating shapes
3. Understand analysis: Read 03-ANALYSIS-FEM-KEYWORDS.md for FEM setup
4. Master components: Read 04-CLASSES-DISTRIBUTIONS.md for parametric design
5. Make models visually clear: Read 26-MATERIAL-VISUALIZATION.md for layer material presets, one-sided surfaces, glass, metal, and highlight materials
6. Practice with CLI: Read 05-FLI-CLI-USAGE.md for running scripts
7. Study examples: Read 06-WORKED-EXAMPLES.md for complete models
8. Build configurator input pages: Read 22-FCC-PLATFORM-INTEGRATION.md and 27-FCC-INPUT-ITEM-ARRAY.md for PVC-backed parameter schemas

Quick Start for AI Agents

Running FCS Scripts

# Evaluate an expression
fli.exe model.fcs "expression"

# Interactive mode
fli.exe model.fcs

# Generate output
fli.exe model.fcs expression --t PNG --o output.png

# Visual 3D model viewer (fliw = fli + WebView viewer)
fliw.exe model.fcs

Basic Syntax

# Variable assignment (value binding)
x := 10
y := x * 2

# Geometry definition
vertex {v1} xyz 0 0 0
vertex {v2} xyz 1 0 0
curve {line1} vertex {v1} {v2}

# Class instantiation
myObj := ClassName{ property1 = value1, property2 = value2 }

# Lambda function
add := a, b => a + b

FCS Language Overview

FCS is a domain-specific scripting language for structural engineering and finite element analysis. Key characteristics:

• Declarative with lazy evaluation
• Expression-oriented - everything returns a value
• Domain keywords for geometry, mesh, materials, loads
• Python-like syntax for expressions
• .fcs file extension

File Dependencies

• Scripts use gclass {name} filename "path/to/file.fcs" for loading components
• Relative paths resolve from the current script's directory

Key Concepts

Domain Objects

• vertex, curve, area, volume - Geometry primitives
• material, thickness, cross_section - Section properties
• beam, planestress, shell - Structural members
• support, load - Boundary conditions
• mesharea, meshcurve - Mesh control

Coordinate Systems

• GCS - Global Coordinate System
• GCS.Tx(d), GCS.Ty(d), GCS.Tz(d) - Translation
• GCS.Rx(a), GCS.Ry(a), GCS.Rz(a) - Rotation

Common Patterns

# Parametric model
span := 10
gblock {member} gclass {memberClass} lcs GCS parameters {length := span}

# Conditional geometry
gblock {opt} gclass {gc} lcs GCS if (hasOptionalPart)

# Array iteration
values := [1, 2, 3]
sum := values.Sum

Testing Scripts

Use FLI to validate scripts:

# Quick syntax check
fli.exe model.fcs "True" --td Warning

# Evaluate specific expression
fli.exe model.fcs "vertex1.X + vertex1.Y"

• gclass {Name} filename "path.fcs" declares reusable classes
• Package structure via .fcsconfig.json