Blender to Unreal Engine tips

Software:
Blender 2.9 | Unreal Engine 4.25

The following is a list of guidelines for preparation and export of 3D content from Blender to Unreal Engine 4 via the FBX file format.

Disclaimer:
This is not a formal specification.
It’s a list of tips I found to work well in my own experience.
* Some of the issues listed here may have already been solved


Blender Scene and model settings:

System units in Blender:
Define the scene units in Blender as:
Metric unit with 0.01 scale (centimeters)
And model your content correctly using centimeter units.
* Modeling in 1 meter units may seem to be imported correctly into UE4 but will cause unsolvable problems like a skeletal mesh physics asset having incorrect auto-generated shapes, a problem that in my experience can’t be fixed manually.

Transform:
Model your model in Blender facing the -Y world axis, +Z obviously being up (obviously for Blender).
* This way the model is aligned to Blender’s views so the front view displays the model’s front etc.
Make sure to apply your model’s transformations before export.

Armatures:
Make sure the Armature object isn’t named “Armature”.
naming or leaving the Blender skeleton named “Armature” will cause the UE4 importer to fail due to “multiple roots”.
* Also remember some weird related bug with animation scale incorrectly imported, but can’t confirm this now..
No need for a dedicated root bone in the hierarchy. the Armature object is the root of the bone hierarchy.
* See export option below

Texture baking:
Set the normal map’s green channel to -Y.
* This is not critical at all because if baked as +Y it can easily be fixed in UE4.

Metadata:
Blender custom properties import as UE4 asset metadata that can be read by editor scripts for automation purposes.
* See export option below


FBX Blender export and UE4 import settings:

I recommend saving an FBX export preset with these settings.

Optional:
I prefer the export settings to include only selected objects.
* It’s more efficient for me to select the specifics objects I want to export into a single FBX file prior to export, than to delete all the temp / reference / draft objects from the scene.
If you want to export Blender custom properties with to the FBX check the “Custom Properties” option

Axes:
Blender’s native model/world orientation is model’s forward facing the -Y axis, left side facing +X and of-course up facing +Z.
UE4’s native model/world orientation is model’s forward facing the +X axis, left side facing -Y and up facing +Z.
There are axis settings in Blender’s FBX export module, that theoretically, should be set like this:

However, in tests I did, The axis settings made no difference when importing to UE4, even when setting intentionally incorrect upside-down axes.
Maybe the FBX exporter writes these settings to metadata that the UE4 importer doesn’t read..
From my experience, what’s important is to orient the model correctly in Blender (see above), apply the transformations,
And in the UE4 import menu, check the “Force Front XAxis” option:

Geometry:
Make sure either “Edge” or “Face” is chosen in the “Smoothing” option to import the mesh’s smooth shading correctly ans avoid a smoothing groups warning on import:

Optional:
Depending on how much control you need over the mesh’s tangent space,
You may want to check the “Tangent Space” export option,
This will make Blender export the full tangent space to the FBX and make UE4 read it from FBX instead of generate it automatically.
* For this option to be supported, the mesh geometry must have only triangle or quad polys.
In the UE4 import settings, choose the “Import Normals and Tangents” option in “Normal Import Method”:

Armature:
Set “Armature FBXNode Type” to “Root”.
Uncheck the “Add Leaf Bones” option to avoid adding unneeded end bones.
Set bones primary axis as X, and secondary axis as -Z.

Animation:
Uncheck “All Actions” to avoid exporting actions that don’t actually belong to the skeleton.
* Un-related animations in the FBX can also corrupt the character rest pose in UE.
The “NLA Strips” option is useful for exporting a library of animations with the skeleton.
* In Blender’s NLA editor, activate the actions you want exported to the FBX.


Related:
3ds max & V-Ray to UE4 Datasmith workflow

3ds max & V-Ray to UE4 – Datasmith workflow basics and tips

Software:
3ds max 2020 | V-Ray Next | Unreal Engine 4.25

This post details basic steps and tips for exporting models from 3ds max & V-Ray to Unreal Engine using the Datasmith plugin.
The Datasmith plugin from Epic Games is revolutionary in the relatively painless workflow it enables for exporting 3ds max & V-Ray architectural scenes into Unreal Engine.
Bear in mind however, that Datasmith‘s streamlined workflow can’t always free us from the need to meticulously prepare models as game assets by the book (UV unwrapping, texture baking, mesh and material unifying etc.) (especially if we need very high game performance).
That being said, the Datasmith plugin has definitely revolutionized the process of importing assets into Unreal, making it mush more convenient and accessible.

 

Preparation:
Download and Install the Datasmith exporter plugin compatible with your modeling software and Unreal Engine version:
https://www.unrealengine.com/en-US/datasmith/plugins

 

In 3ds max & V-Ray:

  1. Make sure all materials are VRayMtl type (these get interpreted relatively accurately by Datasmith)
  2. Make sure all material textures are properly located so the Datasmith exporter ill be able to export them properly.
  3. In Rendering > Exposure Control:
    Make sure Exposure control is disabled.
    Explanation:
    If the Exposure Control will be active it will be exported to the Datasmith file, and when imported to Your Unreal Level/Map a “Global_Exposure” actor will be created with the same exposure settings.
    Sounds good, right? So what’s the problem?
    The problem with this is that these exposure setting will usually be compatible with photo-metric light sources like a VRaySun for example, but when imported to Unreal, the VRaySun does not keep its photo-metric intensity. (in my tests it got 10lx intensity on import). the result is that the imported exposure settings cause the level to be displayed completely dark.
    Of-course you can simply delete the “Global_Exposure” actor after import, but honestly, I always forget its there, and start looking for a reason why would everything be black for no apparent reason…
    * If your familiar with photo-metric units, you can set the VRaySun to its correct intensity of about 100000lx, and also adjust other light sources intensity to be compatible with the exposure setting.
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  5. Select all of the models objects intended for export,
    And File > Export > Export Selected:
    * If you choose File > Export > Export you’l still have an option to export only selected objects..
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  6. In the File Export window,
    Select the export location, name the exported file,
    And in the File type drop-down select Unreal Datasmith:
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  7. In the Datasmith Export Options dialog,
    Set export options, and click OK.
    * Here you select whether to export only selected object or all objects (again)
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  8. Depending on the way you prepared your model,
    You may get warning messages after the export has finished:
    Explanation:
    Traditionally, models intended for use in a game engine should be very carefully prepared with completely unwrapped texture UV coordinates and no overlapping or redundant geometry UV space.
    Data-smith allows for a significantly forgiving and streamlined (and friendly) workflow but still warns for problem it locates.
    In many cases these warnings will not have an actual effect (especially if Lightmap UV’s are generated by Unreal on import), but take into account that if you do encounter material/lighting issues down the road, these warnings may be related.
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  9. Note that the Datasmith exporter created both a Datasmith (*.udatasmith) file, and a corresponding folder containing assets.
    It’s important to keep both these items in their relative locations:
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In Unreal Editor:

  1. Go to Edit > Plugins to open the Plugins Manager:
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  2. In the Plugins Manager search field, type “Datasmith” to find the Datasmith Importer plugin in the list, and make sure Enabled checked for it.
    * Depending on the project template you started with, it may already be enabled.
    * If the plugin wasn’t enabled, the Unreal Editor will prompt you to restart it.
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  3. In the Unreal project Content, create a folder to which the now assets will be imported:
    * You can also do this later in the import stage
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  4. In the main toolbar, Click the Datasmith button to import your model:
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  5. Locate the the *.udatasmith file you exported earlier, double click it or select it and press Open:
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  6. In the Choose Location… dialog that opens,
    Select the folder to which you want to import the assets:
    * If you didn’t create a folder prior to this stage you can right click and create one now.
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  7. The Datasmith Import Options dialog lets you set import options:
    * This can be a good time to raise the Lightmap resolution for the models if needed.
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  8. Wait for the new imported shaders (materials) to compile..
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  9. The new assets will automatically be placed into the active Map\Level in the Editor.
    All of the imported actors will be automatically parented to an empty actor names the same as the imported Datasmith file.
    In the Outliner window, locate the imported parent actor, and transform it in-order to transform all of the imported assets together:
    * If your map’s display turns completely dark or otherwise weird on import, locate the “Global_Exposure” actor that was imported and delete (you can of-course set new exposure setting or adjust the light settings to be compatible)
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Related:

  1. Preparing an FPS project for archviz
  2. Unreal – Architectural glass material
  3. Unreal – Camera animation
  4. UE4 – Archviz Light calculaion tips

Setting Windows 10 Ransomware protection not to block Adobe Photoshop

Software:
Adobe Photoshop 2020 | Microsoft Windows 10

If you encountered this error message when launching Adobe Photoshop:
“There was a problem with Generator. If the problem persits….”
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Chances are it has to do with Windows 10 Ransomware protection blocking it and one of it’s components, and if you continue to working with Photoshop with this problem you’ll find export modules (and maybe other features) not working.

In-order to fix the problem, we have to set Windows Ransomware protection not to block these components:

  1. In the Windows Virus & threat protection settings,
    Click Manage ransomware protection:
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  2. In the Windows Ransomware protection settings,
    Click Allow an app through Controlled folder access:
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  3. In the Allow an app through Controlled folder access settings,
    Click Add an allowed app:
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  4. To avoid having to locate the specific executable files choose Recently blocked apps:
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  5. In the Recently blocked apps select both AdobeGCClient.exe and Photoshop.exe:
    * Click the plus button to add them:
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General note:
You may need to to the same with many other apps.
Every time you get a Windows notification about a process being blocked,
Visit the ransomware protection setting, check what was the last app being blocked and see if it needs to be allowed to operate

That’s it. hope you’ll find this helpful! 🙂

 

 

Exporting 3D camera data from After Effects to 3ds max

Software:
After Effects 2020

  1. Download the AE3D_Export script here:
    http://www.urbanspaceman.net/shared/AEscripts/AE3Dexport/AE3D_Export.jsx
  2. Perform 3D tracking on the footage if necessary.
  3. Select the 3D Camera layer and also Null layers if available.
  4. Choose File > Scripts > Run Script File and locate the AE3D_Export script.
  5. In the Script parameters highlight 3ds max.
  6. Click Options and set the scale.
    * you might need to try and see the scale in 3ds max to set it right.
  7. Set a name for the exported ms (MaxScript) file.
  8. Click Export.
    The resulting MaxScript file will appear on the desktop named <your after effects project name>.ms
    Note:
    You may be prompted to check the Allow Scripts to Write Files and Access Network option in File > Preferences > Scripts & Expressions.
  9. Drag the generated MaxScript file into the 3ds max viewport.
    The script will run and create an animated Camera and Dummy object, and also set the timeline range to fit the animation.
  10. Create a new Point Helper object.
  11. Align the new Point Helper to the Dummy object in both position and orientation.
  12. Group the Camera and the Dummy objects together, and link the group to a new Point Helper.
    This will allow for easy orientation and scaling.
  13. Set the Point Helper object’s rotation to default (0,0,0) , this will also reset the Dummy + Camera group’s orientation relative to the world.
    Scale the Point Helper object if needed, to scale the whole camera setup.
  14. Display the original video sequence as viewport background to check how the camera motion fits the video.
    The center of your Point Helper should appear “glued” to a specific point in the background video. 
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Related:
After Effects 3D Camera tracking