# C# Unity ESP & Bounding Box Visualization Framework

A high-performance C# framework demonstrating real-time in-game bounding box calculations, collider screen projections, Unity `Animator` skeleton bone rendering, and distance-scaled name tags using Unity's `OnGUI` and `Camera.WorldToScreenPoint`.

## Features

- **3D Bounding Box Calculation**: Projects the 8 corner vertices of world-space `Bounds` into screen space and renders 12 connected wireframe edges.
- **2D Screen-Aligned Box**: Computes tight 2D screen bounding rectangles derived from 3D collider extents.
- **Skeleton & Bone ESP**: Traverses `Animator.GetBoneTransform(HumanBodyBones)` to render a full anatomical humanoid skeleton.
- **Name & Distance Tags**: Renders formatted text labels and health bars scaled by camera distance.
- **Occlusion & Viewport Clipping**: Automatically culls entities positioned behind the active camera frustum (`Z > 0`).

## Mathematical Projection Pipeline

### 1. 3D Bounding Box
Given an entity bounding box with center $C = (c_x, c_y, c_z)$ and extents $E = (e_x, e_y, e_z)$, the 8 world-space corners are computed:

$$V_{i,j,k} = C + (\pm e_x, \pm e_y, \pm e_z)$$

Each vertex is transformed to screen space via `Camera.WorldToScreenPoint(V)` and inverted along the Y-axis for Unity GUI coordinates:
$$y_{gui} = \text{Screen.height} - y_{screen}$$

### 2. Bone Skeleton Graph
Humanoid bones are queried using `HumanBodyBones` and connected as line segments:
- **Head & Spine**: `Head` -> `Neck` -> `Chest` -> `Spine` -> `Hips`
- **Left Arm**: `Neck` -> `LeftShoulder` -> `LeftUpperArm` -> `LeftLowerArm` -> `LeftHand`
- **Right Arm**: `Neck` -> `RightShoulder` -> `RightUpperArm` -> `RightLowerArm` -> `RightHand`
- **Left Leg**: `Hips` -> `LeftUpperLeg` -> `LeftLowerLeg` -> `LeftFoot`
- **Right Leg**: `Hips` -> `RightUpperLeg` -> `RightLowerLeg` -> `RightFoot`

## Usage

Attach `ESPManager` to an active GameObject with camera reference:

```csharp
using UnityEngine;
using CSharpESP;

public class ExampleUsage : MonoBehaviour
{
    private void Start()
    {
        ESPManager.Instance.EnableBox3D = true;
        ESPManager.Instance.EnableBones = true;
        ESPManager.Instance.EnableNameTags = true;
    }
}
```

## Structure

```
src/
├── Drawing/
│   └── RenderHelper.cs     # 2D line, box, string, and texture drawing primitives
├── Entities/
│   └── ESPTarget.cs        # Target tracking component with collider/animator bindings
├── Renderers/
│   ├── BoneRenderer.cs     # HumanBodyBones skeleton graph traversal & rendering
│   ├── Box2DRenderer.cs    # Screen-aligned 2D rectangle & corner brackets
│   ├── Box3DRenderer.cs    # 8-vertex 12-edge 3D wireframe bounding box
│   └── NameTagRenderer.cs  # Distance-scaled text label & health bar
├── ESPManager.cs           # Main MonoBehaviour dispatcher
└── MathUtils.cs            # Coordinate projection & bounding math
```

## License

Released under the [MIT License](LICENSE).