Variable Radius Circle Workspace — Java 25 / JavaFX 25

A fresh rewrite of the variable-radius circle workspace. It uses JavaFX controls and canvas rendering instead of Processing.

Requirements

• JDK 25
• Internet access on first Gradle run so Gradle can obtain JavaFX 25 and Jackson

Repository-native AI context

Coding agents should begin with AGENTS.md. It automatically directs them to the project purpose, accepted requirements, mathematical/domain rules, architecture, UI behavior, current implementation state, tests, decisions, and living feature map.

The intent is that normal prompts can describe only the requested change; compatible agents should load the repository context, update affected tests and living documents, and run validation without requiring a separate project introduction. See AI-DLC.md.

Initialize or verify the context on Windows:

powershell -ExecutionPolicy Bypass -File .\setup-agent.ps1 -StageGit

Run

Windows:

gradlew.bat run

macOS/Linux:

./gradlew run

Architectural changes

• Immutable Java records are the model.
• Rotation is recalculated from a directed contact graph on every update.
• slaveContactId is the only source of truth for inherited rotation.
• Powered, slaved, and stopped states are explicit.
• JavaFX text fields commit on Enter and focus loss.
• JavaFX controls provide native caret, selection, scrolling, resizing, and maximization.
• The displayed angle is deterministic: startAngle + effectiveRate × masterTick.

Interaction

• Drag a circle: resets its rotation to 0 and removes its current contacts.
• Release near a 15° tangency candidate: snaps externally or internally.
• Arrow keys: move without snapping and detach contacts.
• Mouse wheel: zoom around the pointer.
• Middle/right drag: pan.
• Inspector: edit radius/diameter/circumference, rotation, rates, contacts, and slave input.
• Contact degree and unit fields update each other through the model.
• Save/Load JSON and Reset Start are available in the toolbar.

JavaFX 25 requires a modern JDK; this project deliberately targets Java 25.

Gradle configuration-cache note

This JavaFX project deliberately disables Gradle's configuration cache. The OpenJFX Gradle plugin currently prepares JavaFX runtime arguments for the run JavaExec task at execution time, which Gradle 9.x does not allow while storing the configuration cache.

If IntelliJ still passes --configuration-cache, the run task is explicitly marked incompatible and Gradle will run it without caching. You can also run:

gradlew.bat --no-configuration-cache clean run