FrankLWC

A lightweight custom controls framework built in F# for Windows Forms, supporting hierarchical composition, 2D transformations, and interactive event handling.

Features

• Custom lightweight controls with arbitrary shapes (rectangles, ellipses, Bezier curves)
• 2D transformations (translate, rotate, scale) both accumulative and non-accumulative
• Hierarchical composition - controls can contain other controls
• Hit-testing with accurate detection on transformed/rotated regions
• Mouse and keyboard events propagated through the control hierarchy
• Double-buffered rendering with anti-aliasing

Architecture

Class	Description
TransformMatrixs	Manages World-to-View and View-to-World transformation matrices
AbstractLWControl	Abstract base defining the interface for all lightweight controls
LWControl	Concrete control that can contain child controls
LWContainer	Root Windows Forms UserControl integrating LWC with WinForms
LWArray	Collection wrapper for managing multiple controls

Usage

Include the framework and create controls:

#load "FrankLWC.fsx"
open FrankLWC

let container = new LWContainer(Dock = DockStyle.Fill)
let control = new LWControl(...)
container.LWControls.Add(control)

See Demo.fsx and Demo2.fsx for complete interactive examples including draggable shapes, animated transformations, and a Bezier curve editor.

Tech stack

• F# (.fsx scripts)
• Windows Forms / GDI+ / System.Drawing.Drawing2D

License

Apache License 2.0 - see LICENSE for details.