CAD Visualizer Tool

A CAD editor built using OpenGL and Win32.

CAD Visualizer Tool – Features Overview

Core Features

3D Scene Editor

• Create, select, transform and delete 3D objects in real-time object.
• Object properties panel.

Rendering

• Grid rendering on the XZ plane for scene orientation.
• Bounding box and vertex visualization for selected objects.
• Object list with selection and delete functionality.
• Dialog for creating new objects with type and parameters.

Camera Controls

• Free-look camera: WASD movement and mouse look.
• Provides Orthographic and Perspective Views.
• Orbit camera: rotate around a target, zoom in/out.
• Seamless switching between camera modes.

Orthographic View

Perspective View

File I/O

• Import 3D models from STL files.
• Support for both binary and ASCII STL formats.

Modular MVC (Model-View-Controller) design for maintainability.

Technical Functionality

Geometry & 3D Modeling

Parametric Primitives

The engine supports mathematically defined primitives (cube, sphere, cylinder, torus, cone, plane, pyramid) with fully editable parameters and transform operations.

Face-Level Selection

Each mesh contains a list of triangular faces, each defined by:

• 3 vertex positions
• Precomputed normal
• Per-face AABB bounds

This enables precise selection and ray-intersection down to the triangle level.

Multi-Mode Bounding Volumes

• Object-Space AABB: Original dimensions before transforms
• Scaled Bounds: Size after applying scale factors
• Tight Bounds (Scale Only): Pre-rotation bounding box
• World-Space AABB: Full transformation applied

Bounding Volume Hierarchy (BVH)

A memory-optimized BVH implementation provides fast ray queries and intersection testing.

Key features:

• SAH (Surface Area Heuristic): Optimal split evaluation
• In-place triangle sorting: Improves cache locality
• O(n) SAH evaluation: Using precomputed left/right surface area arrays

KD-Tree Accelerator

Optimized for balanced space partitioning.

Key Features

• Axis cycling (X → Y → Z)
• Median-based splitting
• Triangle overlap handling
• Non-recursive stack traversal

Ray-AABB Rejection

The engine performs fast AABB tests before expensive triangle checks.
This rejects over 90% of rays early.

Möller–Trumbore Triangle Intersection

The engine implements a high-precision triangle intersection method for face and object selection.

Note:
This application is written in C++14, uses OpenGL for rendering, and the Win32 API for its user interface.