Exporter Plugin Repack - 3d Rad

Blog Title: Breathing Life into Legacy Workflows: The Quest for the Perfect 3D Rad Exporter Plugin

Date: October 26, 2023 Category: 3D Workflow, Indie Dev, Reverse Engineering

If you have been in the 3D trenches long enough, you have a graveyard of software on your hard drive. For many of us who started prototyping games in the mid-2000s, that graveyard has a specific tombstone: 3D Rad.

For the uninitiated, 3D Rad was a gem. It was a free, physics-driven game engine that used a node-based visual scripting system long before Unreal Blueprints made it cool. It was lightweight, powerful, and perfect for car demos, FPS prototypes, and bizarre physics sandboxes.

But 3D Rad had a specific, painful bottleneck: The Importer.

To get custom content into 3D Rad, you couldn't just drag and drop an FBX or OBJ. You needed a specific .rad file. And to make that, you needed the official (and long-abandoned) 3D Rad Exporter Plugin for your 3D software.

Today, I want to dive deep into the archaeology of finding, fixing, and utilizing these plugins, specifically for 3ds Max and Blender.

Bridging the Gap: The Architecture and Necessity of a 3D Rad Exporter Plugin

Summary

3D Rad is a legacy engine. Creating a modern "Runtime Exporter Plugin" (importing FBX/GLTF at runtime) is extremely difficult because the engine was not designed for dynamic geometry generation via external DLLs. 3d rad exporter plugin

Recommendation:

1. For importing models: Write an exporter script for your modeling software (Blender/Maya) that exports to .OBJ or .X (DirectX) format. 3D Rad natively supports these.
2. For gameplay logic: Write a C++ DLL that handles math/physics and exposes functions to 3D Rad's Brain script using ExternalCall.
3. For manipulating meshes: Use the internal Brain commands (MeshAddVertex, etc. - if available in your version) rather than trying to inject memory via a C++ plugin.

The 3D Rad Exporter plugin is primarily used to convert 3D models created in modeling software like SketchUp and Blender into the .x (DirectX) format required for 3D Rad game development.  For SketchUp Users 

The most common version of this plugin is for SketchUp. It allows you to export your designs directly to 3D Rad-compatible formats.  Installation: Download the .rbz file from the 3D Rad Forum.

In SketchUp, install it via the Extension Manager (Window > Extension Manager > Install Extension). Do not simply move the .rbs file into the tools folder manually, as this often fails.

Exporting: Once installed, the "3D Rad Exporter" option should appear under the Tools menu.

Texture Handling: A common issue is textures not appearing correctly after export; this can sometimes be mitigated by ensuring textures are correctly applied to faces rather than groups.  For Blender Users  Blog Title: Breathing Life into Legacy Workflows: The

Blender also has a dedicated 3D Rad exporter addon that enables the creation of custom content like skins and rigged meshes. 

Compatibility: The addon typically requires Blender 2.67 or newer and works on 64-bit Windows systems.

Alternative Method: If the plugin fails, you can export your Blender model as an FBX or OBJ and then use a third-party converter like fragMOTION to finalize it as a .x file for 3D Rad.  Alternative: Using .DAE (Collada) 

If you encounter issues with specific exporter plugins, you can download .dae files from the SketchUp 3D Warehouse and convert them using online converters or open them in SketchUp to use the 3D Rad Exporter tool.  Content Creation Tips 

Coordinate Systems: SketchUp and 3D Rad use different axes; your model might appear "on its side" upon import. This can be fixed by rotating the model -90 degrees on the X-axis in a tool like fragMOTION before the final export.

Importing into 3D Rad: Once you have your .x file, use the RadImp or RadImp .NET tools within 3D Rad to import it as a rigidbody or skinmesh.  3D Rad Lesson 5 - "Creating Custom Content" For importing models: Write an exporter script for

Product Name: RadExporter Pro

Tagline: Seamless 3D to Radiance .rad / .rif Workflow

3.1 Geometry Analysis & Healing

Before export, the plugin validates the mesh integrity.

• Manifold Check: Ensures every edge belongs to exactly two faces, creating a "watertight" volume necessary for Monte Carlo particle tracking.
• Normal Unification: Automatically recalculates face normals to ensure consistent orientation (defining "inside" vs. "outside" the volume).
• Intersection Detection: Flags overlapping volumes that would cause undefined particle behavior in the simulation engine.

Geometry Optimization and Transformation

A naive exporter that simply dumps raw vertices will produce inefficient assets. 3D Rad was built for an era of limited VRAM (Video RAM); thus, the plugin must implement aggressive optimization.

First, the exporter must apply “baking” of transforms. In a source application like Blender, an object might have a location ((5, 0, 0)), rotation ((90°, 0, 0)), and scale ((2, 2, 2)). The .rad3D format stores vertices in object space only; it does not support a transformation matrix. Consequently, the plugin must compute the world-space vertex positions by multiplying each vertex by the object’s combined matrix, then write the absolute values. The object’s pivot point is lost upon export, meaning that animations or constraints in 3D Rad must be applied to a dummy parent object, not the mesh itself.

Second, the plugin should perform vertex welding and optimization. Since 3D Rad lacks advanced LOD (Level of Detail) generation, the exporter should offer an option to remove duplicate vertices based on a user-defined epsilon (e.g., 0.0001 units). Furthermore, the plugin must recalculate normals if the source geometry uses smoothing groups or edge splitting, because 3D Rad ignores explicit edge data and relies entirely on per-vertex normals for shading.