Block 7. Preparing a model for a game engine

#The idea of the block

The model has lived entirely inside Blender so far. Block 7 is about the last step, which often fails precisely because it seems a formality: a correct export. A model that looks perfect in Blender can arrive in another application a hundred times smaller, turned on its side or with black faces instead of color. The cause is always one of three: transforms, scale, normals.

#Session 17 — three things that break an export

A live illustration: a model deliberately left unprepared (transforms not applied), right after being imported into a test environment, looks deformed or the wrong size. This is what will happen to your model if you skip the checklist.

1. Apply Transform. Object → Apply → All Transforms. There is the “visible” size and rotation of an object and its real internal data (Scale, Rotation) shown in the N-panel. If you don’t apply them, the receiving engine can interpret these numbers its own way, and the object will “drift”.

2. Units and scale. The key fact of 2026: Blender 5.x is metric by default (1 unit = 1 meter), while Unreal Engine counts in centimeters. A cube with a side of “1” in Blender is a meter: roughly a person’s height, not a house and not a button. If it looks wrong by eye, that’s the signal to check the scale before exporting.

3. Names. Meaningful names for objects and materials instead of Cube.004.

Practice: the checklist on your own object. Go through your model: Apply Transform; check the scale (does the object look a reasonable size next to a standard 1-meter cube); check the names.

#Session 18 — normals and the format for your target

Why can a model look fine in Blender but “go black” in places after export? Because of normals. Turn on Overlay → Normals or Face Orientation (blue/red coloring of faces): a face that “looks” the wrong way simply disappears or goes black after export into an engine with backface culling. The quick fix is Recalculate Normals (Shift+N).

The format for your target:

Format	When	Why
GLB	the web, your own AR showcase (block 8), Godot	compact, opens reliably right in the browser
FBX	Unity, Unreal Engine	the most proven format for exactly these engines

Both formats “pack” geometry, materials and (if needed) a rig with animation into one file. The choice depends not on the model’s quality but on where it goes next.

Practice: exporting. Pick your target (an engine or the web/AR showcase) and export your object in the matching format, after going through the whole checklist from session 17. Aiming at block 8? Save a .glb file right away: you’ll need it in the next session.

#Common problems

Problem	Why it happened	The fix
After import the model looks “stretched” or deformed	A non-uniform scale (different Scale in X/Y/Z) wasn’t applied before export	Apply → All Transforms; check the N-panel: Scale must be `1.0` on all axes
The model’s color is lost: everything is grey after export	Only Viewport Display Color was used, not a real material (Principled BSDF with a Base Color)	Make sure the object has a full material with a filled Base Color, not only a visual color in the viewport
Faces partly go black or disappear after import	The normals of some faces “look” the wrong way	Face Orientation overlay → find the red faces → select them and press `Shift`+`N` (Recalculate Normals)

#Before the session

Blender 5.2 LTS and your object from block 6.
A simple online or local GLB viewer to check exported files: any quick way to open a .glb and see the result is enough.
Aiming at the AR showcase? Save the .glb version of your object right now.
A useful 2026 pipeline checklist is on the Resources page.

#The idea of the block

#Session 17 — three things that break an export

#Session 18 — normals and the format for your target

#Common problems

#Before the session

Terms in this block

Further reading and watching