Game-ready Lowpoly asset from Fusion 360 Workflow Guide

dastagir

Hi all! 

I wanted to use Fusion 360 in a gamedev pipeline and here is a solution I found to archive the best result for this purposes. The goal was to boost my workflow speed and get rid of routine work such as retopology and unwrapping. I use Fusion 360 for modeling but you can use CAD software that you want. So I made a little guide and maybe it will be helpful for you.

Here is an example of a simple asset made in 11 hours with this method.

 Scheme of this pipeline



All magic is done by awesome MoI3D!



In some cases, high poly from MoI3D has little holes on hard edges because of not welded vertices. You can reduce it using max value of outputted polygons that MoI3D can provide.  Also, to avoid this you can import .sat file in 3dsMax and then export it as .fbx but sometimes output .fbx mesh has some problem with smoothing groups. Another solution to get a .obj high poly is to save it from myhub.autodesk360.com (select your high poly model file and in the top right corner you will find a download button. Choose .obj and file would be sent on your email)

RizomUV has amazing align tools so I recommend you to finalize UV mapping with these tools. Baking results will be better with straight vertical/horizontal edges




So, this pipeline allows you to use all advantages of CAD modeling and get an autogenerated game-ready asset without any handwork. Maybe low poly is not perfect but you can optimize it a little bit on your own. 

I hope this walkthrough was useful to some and If you have some advice or suggestions please write it. Also, you can check all renders here: https://www.artstation.com/artwork/mqv1QE

zachagreg

Never used CAD modeling except for simple 3d printed housings for things. Will have to give this method a try at some point.

dastagir

zachagreg said:

Never used CAD modeling except for simple 3d printed housings for things. Will have to give this method a try at some point.

Yep, I strongly recommend it for hard surface stuff. You can do everything you want and not worry about topology and shading. Also, Fusion 360 has timeline which is really powerful tool for concepting and modeling.

musashidan

Nice writeup, but you can do all this directly in Max these days using Lazercut and the InsetSG and chamfer modifiers. InsetSG handles normals very well and Lazercut gives us easy to use CAD modeling-esque tools. The Turntopoly modifier can be used for the pre-bake mesh. The extra benefit is that this is all non-destructive and within Max.

Not knocking your efforts, I think it's great that you've shared your workflow and put time and effort into your breakdown and helping others. Just thought I'd let people know that we don't necessarily have to resort to CAD options if we can achieve the same directly within Max.

dastagir

musashidan said:

Nice writeup, but you can do all this directly in Max these days using Lazercut and the InsetSG and chamfer modifiers. InsetSG handles normals very well and Lazercut gives us easy to use CAD modeling-esque tools. The Turntopoly modifier can be used for the pre-bake mesh. The extra benefit is that this is all non-destructive and within Max.

Not knocking your efforts, I think it's great that you've shared your workflow and put time and effort into your breakdown and helping others. Just thought I'd let people know that we don't necessarily have to resort to CAD options if we can achieve the same directly within Max.

Thank you! I've never heard about  Lazercut and InsetSG. I've just seen videos and it looks really cool but I think It has some cons. For example: for low poly boolean you should use meshes with a small amount of polygons and segments and for hi poly more smooth version of it. So you need to boolean twice the same part. But in MoI you can control the amount of segments instantly. 

And I think that Fusion 360 still better in some areas of hard surface modeling because it was created for this. Loft, fillets, chamfer. sweep and other proper tools for hard surface in Fusion are more advanced and stable. Also, Fusion can provide tools that 3ds Max doesn't have, such as a timeline whick is like node-based. It allows you to change every step and all further steps will be recomputed and it works really good.

On videos which I found about Lazercut model was simple and I'm not sure that it would work just as well on more complex models. 
I don't say that only CAD-software is a right tool for hard surface and it can replace 3ds Max. I think that 3ds Max and Fusion 360 complement each other fine and in some cases CAD is better in some 3ds Max is better

Sorry, my English is not so good. I hope you understand what I mean

oglu

in some cases such CAD based modeling tools arnt bad.
but you have choose the right assets. 

this one here would take me longer to model in maya than in Fusion/Moi.
https://www.artstation.com/artwork/nQ4Av6

musashidan

@dastagir Absolutely nothing wrong with your English. I wish I could write as well as you in a second language.

Just a few things I'd like to pick up on:

1 - there is no need to create a 2nd version of the mesh for the highpoly. When I'm building the lowpoly I will always put enough segments on my curves to ensure the silhouette reads well. Having much smoother highpoly curves will lead to waviness in the bake. Also, Max's booleans are non-destructive and you can adjust the operand segments if you really need to. My highpoly is basically a clone of my lowpoly with a chamfer or InsetSG modifier and a turbosmooth modifier(non-destructive)

2 - Max's spline tools(and now with spline booleans) are excellent - the best of all the DCCs - and Lazercut adds even more functionality. Max has Sweep/Loft/Lathe tools/modifiers.

3 - for me, unwrapping is more efficient in Max because I can unwrap before I triangulate through the TurntoPoy modifier(again, non-destructive) The advantage of this is that I can unwrap quad strips. I unwrap all my cylindrical islands, including tube caps, to rectangles so doing this before triangulating is ideal. Because you're unwrapping a triangulated mesh you will have issues. I've tried this in Rizom with poor results.

Now, I'm not arguing that Max is better at CAD style modeling than a purpose-built CAD program. I've used F360 on a few projects and it is a great program, but for me, I prefer working in a polygon environment because it's much more flexible and I can use all my polygon mesh tools and still have a CAD-like workflow. I'm a great believer in always trying new tools and looking to improve my workflow, but for production assets I really don't see enough of an advantage to warrant adding yet another program to my pipeline.

Yes, the timeline in F360 is a handy feature, but I only ever used it when I was learning the program and made mistakes due to not being experienced enough. Once I got the hang of F360 I never needed it.

dastagir

@musashidan   Yep, you are right about waviness I forgot it. And frankly, the reason why I started using Fusion 360 is that I saw MOP boolean workflow in Modo and was amazed by it but in Max I could not reach that quality. But now Lazercut + Booleans on splines looks promising so I will try it for concepting and drafting. 
And I want to thank you because I've learned a lot of things from your tutorials on youtube
What is DCCs?

zachagreg

DCC means Digital Content Creation, software like Modo, Maya, Max, etc.

dastagir

@musashidan   Yep, you are right about waviness I forgot it. And frankly, the reason why I started using Fusion 360 is that I saw MOP boolean workflow in Modo and was amazed by it but in Max I could not reach that quality. But now Lazercut + Booleans on splines looks promising so I will try it for concepting and drafting. 
And what is DCCs

dastagir

@musashidan   Yep, you are right about waviness I forgot it. And frankly, the reason why I started using Fusion 360 is that I saw MOP boolean workflow in Modo and was amazed by it but in Max I could not reach that quality. But now Lazercut + Booleans on splines looks promising so I will try it for concepting and drafting. 
And what is DCCs

cptSwing

@musashidan you're certainly making me look at Lazercut again (though the hotkey stuff doesn't interest me in the slightest, if I'm honest) ...

Are you doing okay with the single-computer-locked license? I use two computers on the regular and am increasingly annoyed with software/plugins not allowing me to seamlessy shift between them.

brandiqa

Thanks for sharing your workflow. I was also exporting CAD files from Fusion to Moi3D. However, I've changed the process and this is what am doing now:

1. Export from fusion 360 in STL format (with no fillets)
2. Import in Blender 2.8
3. Split the mesh into logical objects
4. Use Blender tools and HardOps addon to convert tris into quads and NGons (a bit of manual work might be required)
5. Create a duplicate for HP and use HardOps to add bevels(fillets) to sharp edges
6. Add details and decals to the mesh using Decal Machine
7. Use HardOps to unwrap* (am still experimenting with this) the LP version
8. Use Substance Painter to bake and texture the mesh

Steps 6 to 8 I haven't actually done it, but here's a model I did last week where I followed steps 1 to 5.

brandiqa

Quick note, when it comes to unwrapping, I find the TextTools addon for Blender and the UV Packmaster addon to be extremely helpful. Unfortunately, TextTools is only available in 2.8 at the moment.

zachagreg

If you're going to use HardOps in Blender I don't understand why you would use Fusion or any CAD software to begin with unless you were specifically given the task to convert CAD files into a usable game format. You're doing all this manual separation and cleanup in Blender when it can just be modeled in Blender from the start. Or Max, Maya or Modo for this instance. 

I appreciate the sharing of methodology but I just fail to see the overall use or how it is more efficient. Doing hardsurface that way just adds more software and more steps. Unless there is a very specific tool or use case that I'm just not aware of I can't see how this would ever be used over just buying box cutter for Blender and using it inline with the already mentioned HardOps and DecalMachine.

musashidan

@zachagreg This is exactly what I was getting at above. There is nothing in any of those CAD programs that can't be done now just as easily in Max/Maya/Blender/Modo, and without the hassle of an extra program(2 in this case) and pure polysoup CAD>Poly meshes. There have been some great advances in hard-surface modeling in the last few years(mostly from Blender) so I really don't see any gains at all.

It's great, though, when people post up findings from their workflows because it gets a discussion going, it makes people think and reevaluate their own workflow. Shit, I'm constantly trying to improve mine by whatever means necessary. We never stop learning in this game. Even now, I'm in the early stages of testing a new Blender baking workflow that doesn't even need a high poly at all.

AlecMoody

What meshing software is that? Mol3d google doesn't seem to come up with the right stuff.

musashidan

@AlecMoody Moment of Inspiration moi 3d

RacePeaceDay

Is moi3d retopo better than in Fusion360?

musashidan

RacePeaceDay said:

Is moi3d retopo better than in Fusion360?

Yes, I believe it is, but I haven't used F360 in over 2 years and the polygon mesh output was pretty terrible. Moi seems to give cleaner meshes.

zachagreg

musashidan said:

@zachagreg This is exactly what I was getting at above. There is nothing in any of those CAD programs that can't be done now just as easily in Max/Maya/Blender/Modo, and without the hassle of an extra program(2 in this case) and pure polysoup CAD>Poly meshes. There have been some great advances in hard-surface modeling in the last few years(mostly from Blender) so I really don't see any gains at all.

It's great, though, when people post up findings from their workflows because it gets a discussion going, it makes people think and reevaluate their own workflow. Shit, I'm constantly trying to improve mine by whatever means necessary. We never stop learning in this game. Even now, I'm in the early stages of testing a new Blender baking workflow that doesn't even need a high poly at all.

I see you on that Bevel shader, I see you

musashidan

zachagreg said:

I see you on that Bevel shader, I see you

Haha! You got me. It bakes down so well. Quality of the baked bevels really surprised me. Gamechanger for me. Honestly, I haven't touched Max 2020s new Chamfer modifier since.