Sketchup to Max double faced objects

[efilana]

Hello guys!

 

I received a Sketchup model for rendering and I decided to export it to Max. I had very bad luck doing so. I followed this path: export as 3ds file, single object, import to Max. With Max 2010 and 2011 I got many objects inverted, so I had to detach-flip them all manually. I also had a lot of them with two faces, so one had to be deleted. With Max 2014 none of the objects were inverted, but many of them were still double-faced (one face seems to be of original Sketchup texture, another - added texture in SU). Of course, I can clean it all manually, but it is the least productive method for a cityscape.

I was wondering, what went wrong and how I can achieve beautiful result that for example, Ramyhanna had.

I am attaching the image for illustration.

 

I will appreciate any insight.

Thank you.

[John Dollus]

garbage in = garbage out. There's a right way and a wrong way to model in SketchUp and most people don't seem to know the difference.

In SketchUp, go to View->Face style->monochrome. Any surface that shows up as purple is facing the wrong direction and will need to be reversed. There's a script out there somewhere to help with that. from what I recall, sketchUp's method for assigning separate materials to each side of a face makes importing into max problematic. If materials are assigned by layer in Sketchup instead of by poly, the import results are improved.

[numerobis]

i have set the backface colour to a neon green so that i can spot reversed faces easily.

And i have a hotkey (^) assigned for the "Revese Faces" command so that i can switch them with one click.

I never assign materials to the backside of a face (only for transparent materials, where textures get assigned

automatically to the backfaces too)

[efilana]

Haha! It's a funny story guys! I did turn faces into monochrome and it was OK, they all were white, until I changed the color of the faces! The wrong side color was set to white and now almost entire model is green. I am sure now I know what happened, because the green showed up exactly where it was reversed in Max! And reversing in SU is so much easier then in Max. This is a revelation to me thank you very much! My Max will love me now.

 

I have a question to you, John: how do I model in SU, so it doesn't happen?

[Dimitris Tolios]

You have to model in a "clean" way...just like with all programs, and use groups/components wisely.

 

I live by the "Cleanup 3" plugin by ThomThom when trying to clean things other gave me.

http://sketchucation.com/forums/viewtopic.php?t=22920

 

Also the "remove materials" plugin from Smustard can help a lot with "nested" materials (materials applied in geometry within groups/components).

http://www.smustard.com/script/RemoveMaterials

[efilana]

Dimitris, I will try those plug-ins, thanks you!

 

Would it be correct to assume that in a model like this 3D shapes were not extruded, but constructed face by face? Because I can't imagine any other way for this to happen.

 

Sample to illustrate. Green is wrong side.

 

PS: Cool location Dimitris

[numerobis]

I have a question to you, John: how do I model in SU, so it doesn't happen?

 

you can never avoid it completely. You have to control it all the time and hit reverse if you find some.

And reversed faces are not only a problem for rendering but also for some modeling actions that like joint pushpull.

 

edit:

yes, normally you should get it right, if you extrude a face, but only if this face is not connected to other faces. If the geometry gets more complex it is sometimes interpreted wrong by the pushpull tool.

 

And as Dimitris said, use groups and components to organize the model!

Edited July 25, 2013 by numerobis

[Dimitris Tolios]

You can import from almost any 3D suite into SU and keep going.

Plus there are loft and other spline like tools/plugins for SU that can get you far from what a simple extrude gets you at.

[efilana]

Thank you guys for all your help. You say things no tut says

[M V]

I also use ThomThom's UV Toolkit2 to place the back face material onto the front face material, then you can use the FrontFace plugin to reverse all the backfaces. The nice thing about FrontFace is that you don't have to go into the groups to reverse them, just move your mouse over it.

 

TIG has also developed a plugin to handle this issue but I have not yet tested it. http://sketchucation.com/forums/viewtopic.php?t=30107

Edited July 9, 2013 by valerostudio

[efilana]

Valerostudio,

 

that sounds really easy. Exactly what I was looking for. Thank you!

 

E.

[Jason Matthews]

I will add that sketchup does not like planes without thickness near other planes. I run into this all the time when doing pavement and parking stripes. Where at all possible, give the planes thickness and if you have say a parking stripe as a modeled geometry sitting on top of a plane of parking, you may be better off stamping the parking stripes on the pavement. This causes issues when rendering in Max. I also model by layer so that I can simply select the layer in Max using the select by name tool, assign the material, give it a UVW map and call it a day. To make life easier, I also create a filter in the select by name and give it a prefix called "Layer". Then I turn on the filter and it removes all of the extraneous naming such as "block".

[M V]

I would be interested in a deeper discussion on SU to MAX workflows that work. First, what importing format do you use? Do you import SKP or do you export to 3DS or OBJ?

[xEndlessxUrbiax]

You do not need to export a Sketchup file if you have 3dsMax version 2009 or later (I think you need a plugin for 2009, however), because 3dsMax can import your sketchup file as it is. You just have to be smart in how you model and texture. The biggest advantages IMO is the ability to texture in Sketchup, and to have those textures import in Max for tweaking or remaking. You don't have to reapply textures in Max. Also, modeling simple shapes in Sketchus is a breeze, which is a huge plus for me.

 

A couple things you have to be aware of in SU, if you are to import the file to Max: Use groups and components wisely (3dsMax recognizes the components from SU as "instances" so if you change one in max, it'll change them all), texture different materials with different materials (in max when you fix the materials, it will fix all the materials named the same, so don't paint your black metal the same material as your black plastic in sketchup, they need to be two different materials from the start. I model everything on Layer0, and apply my different layers to the groups (I don't have anything that isn't inside a group or components. Some of my groups go 5 or 6 deep which is totally fine). Scenes do not import into Max, you will have to create a camera in Max (that's a good thing). On import, choose the option to move all your texture files to one central location. Big models should be imported in sections (seperate interior/exterior/landscaping...)

 

That's my way of going at it, there are many other ways but this is what works best for me.

[numerobis]

That's the way i do it too.

 

But i have to add that importing scenes/cameras is working fine. The only thing you have to do is to adapt the aspect ratio and to change the target distance of the created cameras, because sketchup cameras doesn't have a target distance.

[M V]

2 questions -

How easy is it to convert the imported materials to Vray?

Is it possible to have the SU file linked so if if you update the SketchUp model, all you need to do is reload it?

[xEndlessxUrbiax]

Converting materials is easy, you can create a new material as you normally do it and 'switch' the SU material to your VRay material by right clicking on the SU material and selecting the "Change Material/Map Type" option and choose your VRay material. Everything that had the original material assigned to it, now has your new one.

 

I don't think you can link the SU file, usually you want to get to 3dsMax after you are completely done modeling. If I see I have to fix the ceiling for example, I'll delete that portion from the Max file and fix it in SU. Whatever you have showing in SU when you save is what will import into Max upon import. So just hide everything but the ceiling and import that back in.

[M V]

Isn't there a utility that you can convert the entire file to V-Ray? I think I have seen it upon right clicking on the viewport.

[xEndlessxUrbiax]

I personally don't use V-Ray, I use iRay and Mental Ray. The materials that max imports from SU are by default "Arch and Design" materials. But you can convert any material to any other material (I'm assuming V-Ray too) by right clicking on the material inside of Max and choosing the "Change Material/Map Type" option. I don't think the file can be V-Ray or Mental Ray or Iray or whatever you use to render. Those are the rendering engines inside of 3dsMax and you can choose that option from the render menu if you hit F10 and scroll to the bottom of the Assign Renderer tab.