The Unreal Engine 5 is using "Nanite" to virtualize geometry and achieve detailed rendering of high poly objects. The constant improvement of technology is already changing classic workflows and will influence more and more fields. All of a sudden, the lowpoly pipeline is no longer relevant. Artists can now insert complex geometries into the engine and edit dense 3D meshes without the usual effort and time requirements. This will lead to the need of visual developers and the evolution of game artists, that are used to the creation of super compressed models.
After the new Matrix movie and the playable games made with UnrealEngine 5, the hype is definitely real. As more topics regarding UE5 are being revealed and researched, we took a look into the implementation of CAD models into UE5. As anyone, that had to deal with this issue, will confirm, this has not been without problems in the past. Through the use of datasmith, UE5 promises a more fluent workflow, no matter which program the CAD model is created in. But is UE5 a gamechanger for CAD in realtime? May it be Rhino6 or autocad, the weltfern team researched the possibilities and has some exciting insights.
CAD in Realtime
Computer aided graphics (CAD) is the industry standart for production. Manufacturer requires a model in .step or .stl format from their engineers or product designers. In fact all volume and strength calculations necessary to produce any product / part need CAD files as input (even 3D printer).
However, as soon as this product is expected to make a profit and needs product renderings, we will need it in polygons. Because of that everyone faces the issues with CAD conversions. Graphic cards render polygons and real time engines need conversion to visualize properly.
UE5 presents the possibility of making this process unneccessary. Their offer of using datasmith for the implementation of CAD models in UE5 is on of the engines key features.
With the internal tool Datasmith, Epic has created a very powerful tool (including plugins for all major 3D tools) that can even read runtime CAD formats covert them on the fly and load them into the engine. While the workflow becomes easier and faster, we cannot forget though, that the imported models are still delivered by the industry.
Import quality depends on the source
If you are dealing with CAD imports into UE, you have already familiarized yourself with the Datasmith documentation and the required import steps. If you have not, it is important to note, that a direct import still has to be carefully prepared. As any program UE5 does exactly what the data tells it to do, so any asset visualized has to convey exact information into the engine.
If for example your normals are flipped in Rhino, they will be flipped in UE5 as well, so make sure to check your asset beforehand.
Best Practice to export CAD
In fact, this new approach in no way changes the basic requirement that the source must be perfect. Before implementing a CAD model make sure, that key features of your model are structured and applied correctly. Otherwise mistakes will happen and you will have to deal with hard to fix flaws.
To avoid problems, make sure to follow these steps correctly:
- Normals must face the right way
- A comprehensible layer structure
- Add materials correctly with purpose
- Group or connect objects as necessary
Best practice to use CAD in UE5
After making sure the layer structure is comprehensible, place-holder materials are applied and the model is without any flaws, you can simply export the model through the rhino-datasmith plug-in. Afterwards you can then simply import and update the datasmith file through the UE-datasmith plug-in. Don't be surprised though, the model will be functional but probably not pretty.
Shading issues and low quality materials will present themselves. Datasmith keeps the layer structure of CAD models, as well as materials. Since we applied named materials to all parts and layers we will have an easy time fixing any issues with the model.
A linear workflow in UE5 creates new tasks
Easy access, no Lowpoly but...
Thanks to the Internet, anything we advertise nowadays must be multimedia. Therefore our model won't simply stay inside of Unreal and be content with a simple render. However we cannot forget, that the model used, is still an imported CAD model and thus still has a high poly-count.
After production rework again
Now there is just the question about what to do next? How do we get the data out of UE 5 again and make it processable?
It is important access and delve deeply into the CAD production models. The correct export influences the entire downstream production. During the whole process we have kept the highpoly workflow, so the situation outside UE has hardly changed. Implementing the model has certainly become easier, but you also lose touch with the actual structure and data size.
This might answer the question "Is UE5 a gamechanger for CAD in realtime?". We think for a special workflow yes definitely!
At weltfern we tackle any challenge directly to be able to act efficiently in the workflows. If you have questions or need support get in touch.
Unreal Engine 5
All images and screenshots were taken for research purposes only, neither them nor the projects are for comercial use.