Implement Polygon Shapes #38

New Issue

2026-03-27T23:18:17Z

thib8956 commented

2026-03-27 23:18:17 +00:00

Overview

Add support for freeform polygon shapes with custom vertices.

Current State

Fixed shapes: Rectangle, Circle, Triangle
No support for arbitrary polygons
Triangle has 3 fixed vertices based on position

Implementation Plan

1. SPolygon class

Create new SPolygon extending AbstractShape
Store list of Point vertices
Calculate bounds from vertices

2. Polygon creation

Click multiple points to define vertices
Press Enter or double-click to complete
Minimum 3 points for valid polygon

3. Resizing polygons

Scale proportionally when resized
Or adjust individual vertices (advanced)
Initial implementation: scale all vertices from center

4. Rendering

ShapeDraftman: draw polygon with Graphics2D.drawPolygon()
SVGDraftman: emit
HTMLDraftman: use clip-path polygon or SVG background

5. ShapeVisitor updates

Add visitPolygon(SPolygon) to ShapeVisitor interface
Update all visitor implementations

6. Attributes support

ColorAttributes: fill and stroke colors
SelectionAttributes: selection state
Hit testing: use Polygon.contains() or ray casting

Files to create/modify

Create: shapes/SPolygon.java
Modify: ShapeVisitor.java - add visitPolygon method
Modify: ui/ShapeDraftman.java - implement visitPolygon
Modify: ui/visitors/SVGDraftman.java - implement visitPolygon
Modify: ui/visitors/HTMLDraftman.java - implement visitPolygon
Modify: App.java - add Add Polygon menu item

Edge cases

Less than 3 points: invalid, do not create
Self-intersecting polygons: valid but fill may look odd
Very small polygons: minimum size constraints
Open polygon vs closed: always close the shape

## Overview Add support for freeform polygon shapes with custom vertices. ## Current State - Fixed shapes: Rectangle, Circle, Triangle - No support for arbitrary polygons - Triangle has 3 fixed vertices based on position ## Implementation Plan ### 1. SPolygon class - Create new SPolygon extending AbstractShape - Store list of Point vertices - Calculate bounds from vertices ### 2. Polygon creation - Click multiple points to define vertices - Press Enter or double-click to complete - Minimum 3 points for valid polygon ### 3. Resizing polygons - Scale proportionally when resized - Or adjust individual vertices (advanced) - Initial implementation: scale all vertices from center ### 4. Rendering - ShapeDraftman: draw polygon with Graphics2D.drawPolygon() - SVGDraftman: emit <polygon points="..."> - HTMLDraftman: use clip-path polygon or SVG background ### 5. ShapeVisitor updates - Add visitPolygon(SPolygon) to ShapeVisitor interface - Update all visitor implementations ### 6. Attributes support - ColorAttributes: fill and stroke colors - SelectionAttributes: selection state - Hit testing: use Polygon.contains() or ray casting ## Files to create/modify - Create: shapes/SPolygon.java - Modify: ShapeVisitor.java - add visitPolygon method - Modify: ui/ShapeDraftman.java - implement visitPolygon - Modify: ui/visitors/SVGDraftman.java - implement visitPolygon - Modify: ui/visitors/HTMLDraftman.java - implement visitPolygon - Modify: App.java - add Add Polygon menu item ## Edge cases - Less than 3 points: invalid, do not create - Self-intersecting polygons: valid but fill may look odd - Very small polygons: minimum size constraints - Open polygon vs closed: always close the shape

thib8956 referenced this issue from a commit

2026-03-27 23:57:48 +00:00

Implement #38: Polygon Shapes

thib8956 referenced this issue

2026-03-27 23:58:11 +00:00

Implement #38: Polygon Shapes #45

thib8956 referenced this issue from a commit

2026-03-28 00:32:08 +00:00

test: add comprehensive SPolygon unit tests for PR #45

thib8956 referenced this issue from a commit

2026-03-28 00:33:35 +00:00

test: add comprehensive SPolygon unit tests for PR #45