Reforge - Defold Scene Exporter (Blender Add-on)

Blender add-on for exporting scenes into a Defold project as:

• .glb meshes
• .model files (supports multiple materials)
• .go prefabs (created once, never overwritten)
• .collection scene file (instances grouped under embedded root)

Also supports optional convex collision export per prototype and texture export into your Defold project.

The add-on can be installed directly from Blender without manual downloads.

Just open Edit → Preferences → Extensions, search for Reforge, and install it with one click.

No more ZIP files — updates are handled automatically through Blender.

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Local Installation

1. Go to the Reforge releases page: https://github.com/ufgo/reforge/releases
2. Download the desired version (reforge-.zip).
3. Open Blender.
4. Navigate to: Edit → Preferences → Add-ons
5. Click Install from Disk… and select the downloaded ZIP file.
6. Enable the Reforge add-on in the add-ons list.

The Reforge panel will appear in:
3D Viewport → Sidebar (N) → Reforge

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Features

Scene export

• Generates a Defold .collection with instances matching Blender transforms.
• Instances are grouped like:
  • embedded_instances { id: "root" children: "<prototype>" ... }
  • one embedded group per prototype that contains all instances of that prototype.

Prototype export (no scene regeneration)

• Export only assets (GLB + .model + convex collision files) without touching the .collection.
• Useful when you updated a mesh/materials/textures and want to refresh only one prototype.

Multi-material .model

• For each prototype, the exporter creates a .model file with one materials {} block per Blender material slot (unique materials, in slot order).
• Material matching uses the Blender material name (must match the material name in the exported GLB).

Material-driven Defold paths (stored on Blender Materials)

Add custom properties on Blender Material datablocks:

• defold_material (string) — Defold .material path
• defold_texture (string) — Defold texture path (optional)

If these are not set:

• defold_material falls back to Default Material from the add-on UI
• defold_texture is found from the material nodes:
  • Principled BSDF -> Base Color -> Image Texture
• if no image is found, a fallback built-in Defold logo texture is used.

Texture export

When enabled, the add-on copies/saves textures into:

• assets/textures/

Textures are overwritten (no _1, _2 duplicates).

Convex collision export

Per-prototype collision export is controlled via Object custom properties:

• defold_collision (bool) — enable convex collision export
• collision_group (string, default: "default")
• collision_mask (string, default: "default")

For prototypes with defold_collision = true, exporter generates:

• assets/collisions/<proto>.convexshape
• assets/collisions/<proto>.collisionobject

Collision objects are created as STATIC:

type: COLLISION_OBJECT_TYPE_STATIC
mass: 0.0
friction: 0.1
restitution: 0.5

Safe Clear (with Confirmation)

The add-on can remove only exporter-created custom properties from:

• Objects
• Materials used by those objects

Keys removed:

• Object: defold_prototype, defold_collision, collision_group, collision_mask
• Material: defold_material, defold_texture

Each Clear action uses Blender’s confirmation popup.

Installation

1. Save the add-on script as a single .py file (example: defold_scene_exporter.py).

2. In Blender:

   • Edit → Preferences → Add-ons
   • Install… → select the .py file
   • Enable the add-on checkbox

Panel location:

• 3D Viewport → Sidebar (N) → Defold Export

Quick Start

1) Set Defold Project Path

In the add-on panel:

• Defold Project Root → select your Defold project folder

Default folders (editable):

• assets/models
• assets/prefabs
• assets/scenes
• assets/textures
• assets/collisions

2) Tag Objects with defold_prototype

The exporter only includes objects that have custom property:

• defold_prototype

Fast way:

• Use Tools section:
  • 1. Set Props (Selected)
  • 2. Set Props (Visible)
  • 3. Set Props (All)

This creates defold_prototype using the object name.

3) Export a Scene

• Set Collection Name
• Press Generate Scene (.collection)

4) Export Only One Prototype (No Scene Regen)

Select the prototype’s mesh object and press:

• Export Selected Prototype (No Scene)

Setting Up Multiple Materials

How to assign Defold material/texture per Blender material

Select your material → Material Properties → Custom Properties:

Optional:

• defold_material = /assets/materials/my.material
• defold_texture = /assets/textures/my.png

If you don’t set them:

• defold_material uses UI Default Material
• defold_texture is taken from Principled BSDF -> Base Color image node

Collision Setup

On the Blender Object (not Material):

• defold_collision = True
• collision_group = default (or your group)
• collision_mask = default (or your mask)

You can set these quickly using the Tools section in the panel.

Notes / Behavior

.go Prefabs Are NOT Overwritten

• If a .go file already exists, exporter will not rewrite it.
• This is intentional to preserve manual edits (collision setup, scripts, etc).

Files That ARE Overwritten

Per export, for each prototype:

• <proto>.glb
• <proto>.model
• <proto>.convexshape (if enabled)
• <proto>.collisionobject (if enabled)
• the .collection file (when generating scene)

Export Visible Only

If enabled, only objects that are visible in the viewport are exported.

Troubleshooting

“No MESH objects with ‘defold_prototype’…”

• Ensure objects are Meshes
• Ensure defold_prototype exists as a custom property
• Check Export Visible Only and visibility of objects

Textures Create Duplicates Like _1, _2

This add-on overwrites by filename. If you still see duplicates:

• Make sure your Defold textures folder isn’t read-only
• Ensure images have stable filenames (not generated temporary names)

Collision Seems Offset

• Convex hull export uses rotation+scale but not translation (correct for Defold local collision space).
• Avoid negative scale / mirrored objects.
• Apply transforms in Blender if your object has unusual transforms.