From 09a7608bcbd4225cb5260c19ae757d566f59ca7b Mon Sep 17 00:00:00 2001
From: AJ Isaacs <ajisaacs27@gmail.com>
Date: Tue, 17 Mar 2026 08:03:14 -0400
Subject: [PATCH] feat(core): add IsoscelesTriangleShape

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
---
 .../Shapes/IsoscelesTriangleShape.cs          | 25 ++++++++++++
 OpenNest.Core/Shapes/LShape.cs                | 31 ++++++++++++++
 .../Shapes/IsoscelesTriangleShapeTests.cs     | 26 ++++++++++++
 OpenNest.Tests/Shapes/LShapeTests.cs          | 40 +++++++++++++++++++
 4 files changed, 122 insertions(+)
 create mode 100644 OpenNest.Core/Shapes/IsoscelesTriangleShape.cs
 create mode 100644 OpenNest.Core/Shapes/LShape.cs
 create mode 100644 OpenNest.Tests/Shapes/IsoscelesTriangleShapeTests.cs
 create mode 100644 OpenNest.Tests/Shapes/LShapeTests.cs

diff --git a/OpenNest.Core/Shapes/IsoscelesTriangleShape.cs b/OpenNest.Core/Shapes/IsoscelesTriangleShape.cs
new file mode 100644
index 0000000..125127f
--- /dev/null
+++ b/OpenNest.Core/Shapes/IsoscelesTriangleShape.cs
@@ -0,0 +1,25 @@
+using System.Collections.Generic;
+using OpenNest.Geometry;
+
+namespace OpenNest.Shapes
+{
+    public class IsoscelesTriangleShape : ShapeDefinition
+    {
+        public double Base { get; set; }
+        public double Height { get; set; }
+
+        public override Drawing GetDrawing()
+        {
+            var midX = Base / 2.0;
+
+            var entities = new List<Entity>
+            {
+                new Line(0, 0, Base, 0),
+                new Line(Base, 0, midX, Height),
+                new Line(midX, Height, 0, 0)
+            };
+
+            return CreateDrawing(entities);
+        }
+    }
+}
diff --git a/OpenNest.Core/Shapes/LShape.cs b/OpenNest.Core/Shapes/LShape.cs
new file mode 100644
index 0000000..3712aa2
--- /dev/null
+++ b/OpenNest.Core/Shapes/LShape.cs
@@ -0,0 +1,31 @@
+using System.Collections.Generic;
+using OpenNest.Geometry;
+
+namespace OpenNest.Shapes
+{
+    public class LShape : ShapeDefinition
+    {
+        public double Width { get; set; }
+        public double Height { get; set; }
+        public double LegWidth { get; set; }
+        public double LegHeight { get; set; }
+
+        public override Drawing GetDrawing()
+        {
+            var lw = LegWidth > 0 ? LegWidth : Width / 2.0;
+            var lh = LegHeight > 0 ? LegHeight : Height / 2.0;
+
+            var entities = new List<Entity>
+            {
+                new Line(0, 0, Width, 0),
+                new Line(Width, 0, Width, lh),
+                new Line(Width, lh, lw, lh),
+                new Line(lw, lh, lw, Height),
+                new Line(lw, Height, 0, Height),
+                new Line(0, Height, 0, 0)
+            };
+
+            return CreateDrawing(entities);
+        }
+    }
+}
diff --git a/OpenNest.Tests/Shapes/IsoscelesTriangleShapeTests.cs b/OpenNest.Tests/Shapes/IsoscelesTriangleShapeTests.cs
new file mode 100644
index 0000000..f4420a4
--- /dev/null
+++ b/OpenNest.Tests/Shapes/IsoscelesTriangleShapeTests.cs
@@ -0,0 +1,26 @@
+using OpenNest.Shapes;
+
+namespace OpenNest.Tests.Shapes;
+
+public class IsoscelesTriangleShapeTests
+{
+    [Fact]
+    public void GetDrawing_BoundingBoxMatchesDimensions()
+    {
+        var shape = new IsoscelesTriangleShape { Base = 10, Height = 8 };
+        var drawing = shape.GetDrawing();
+
+        var bbox = drawing.Program.BoundingBox();
+        Assert.Equal(10, bbox.Width, 0.01);
+        Assert.Equal(8, bbox.Length, 0.01);
+    }
+
+    [Fact]
+    public void GetDrawing_AreaIsHalfBaseTimesHeight()
+    {
+        var shape = new IsoscelesTriangleShape { Base = 10, Height = 8 };
+        var drawing = shape.GetDrawing();
+
+        Assert.Equal(40, drawing.Area, 0.5);
+    }
+}
diff --git a/OpenNest.Tests/Shapes/LShapeTests.cs b/OpenNest.Tests/Shapes/LShapeTests.cs
new file mode 100644
index 0000000..8c4cd56
--- /dev/null
+++ b/OpenNest.Tests/Shapes/LShapeTests.cs
@@ -0,0 +1,40 @@
+using OpenNest.Shapes;
+
+namespace OpenNest.Tests.Shapes;
+
+public class LShapeTests
+{
+    [Fact]
+    public void GetDrawing_BoundingBoxMatchesDimensions()
+    {
+        var shape = new LShape { Width = 10, Height = 20 };
+        var drawing = shape.GetDrawing();
+
+        var bbox = drawing.Program.BoundingBox();
+        Assert.Equal(10, bbox.Width, 0.01);
+        Assert.Equal(20, bbox.Length, 0.01);
+    }
+
+    [Fact]
+    public void GetDrawing_DefaultLegDimensions()
+    {
+        var shape = new LShape { Width = 10, Height = 20 };
+        var drawing = shape.GetDrawing();
+
+        // Default legs: LegWidth = Width/2 = 5, LegHeight = Height/2 = 10
+        // Area = Width*Height - (Width - LegWidth) * (Height - LegHeight)
+        // Area = 10*20 - 5*10 = 150
+        Assert.Equal(150, drawing.Area, 0.5);
+    }
+
+    [Fact]
+    public void GetDrawing_CustomLegDimensions()
+    {
+        var shape = new LShape { Width = 10, Height = 20, LegWidth = 3, LegHeight = 5 };
+        var drawing = shape.GetDrawing();
+
+        // Area = Width*Height - (Width - LegWidth) * (Height - LegHeight)
+        // Area = 10*20 - 7*15 = 200 - 105 = 95
+        Assert.Equal(95, drawing.Area, 0.5);
+    }
+}