TEXTURES Exporting SketchUp Models to Substance Painter UV Mapping Wrapping Unwrapping

Does anyone have any recommendations for exporting models into Substance Painter in such a way that materials automatically create different texture sets?

I have a model of a real-work two-family flat that I really want to create a super realistic interactive rendering from. To do that, I need textures that have no repetitions, which I followed this tutorial to create: https://academy.allegorithmic.com/courses/Creating-endless-textures-with-Substance-Designer-and-3DsMax/youtube-FuPQNIx3dh8

Since I want to do this with many structures that use a limited number of materials overall, it seems worth it to me to invest in creating some really detailed high performance textures.

Real world structure:

SketchUp Model (W photo texture - note not all the geometry is finished):

SketchFab Model:

Close up of actual facade:

Fancy Texture created in Substance Designer (being imported into Substance Painter):

Iā€™ve tried exporting as FBX, but SketchUp crashes every time I do it

Iā€™ve tried exporting as OBJ, but I canā€™t import the mtl file Substance Painter. Best I get is the single mesh that I canā€™t select different parts of the model in (i.e I canā€™t select portions of the mesh by material)

Iā€™ve tried exporting as DAE, but the import fails because of something related to not having recognizable UV values?

Iā€™m having a hard time figuring out the best way to go about doing this. Maybe I need to be triangulating meshes, or selecting some specific features in the export options, but Iā€™m not sure how to make sense of most of it. Iā€™ve watch hours of tutorials from Substance Painter, but they pretty much only cover how 3DS Max or Maya can interact with SketchUp and I donā€™t know enough about whatā€™s happening to connect the dots back to SketchUp.

Hereā€™s what the import screen looks like in Substance Painter:

If anyone has any recommendations for something better than substance designer, Iā€™d love suggestions there as well. Any assistance would be appreciated!

Hi Tyson
From what I have found, the fundamental reason why it is very difficult to use Substance Painter with SU (and whatever your target renderer is) are the way SU Handles UVā€™s (basically, it doesnā€™t really) a good UV unwrap is what Painter needs in order to do what you want - i.e. paint on dirt, grunge, surface imperfections etc along with a created texture on specific parts of a model.

Generally, looking at what you are trying to achieve, you need to break the model down into smaller parts/groups/components, i.e. the roof the walls etc - much like the way you would do it in SU. Then each part unwrapping and a UV map created for use in Painter.

If you are on a Windows machine, there is an fantastic utility called WrapR, which is specifically designed to work with Sketchup model files in order to UV unwrap and create/save the UV map, which you can then use in Painter.

There are some posts on this forum that touch on a Substance workflow using WrapR.

Unfortunately for me, Iā€™m on a Mac so no WrapR for me! (I am very sad about this)
I use Substance Designer all the time but it is to create the textures and outputs that I apply with the standard SU and Vray tools. I also use Fredoā€™s thrupaint and SketchUV. I think there might be a way using just the latter 2 extensions but I havenā€™t had time to really pick the bones out of that approach.

At some point I would imagine / hope that the SU team will have time address the way SU handles textures and UVā€™s in future releases. SU is more and more being used for visualisation and the meteoric rise of Substance and integrations into DCC workflows bodes well for this. Vray Next is adding support for Metallic / Roughness PBR workflows (to support Substance outputs) so that may make it into a future Vray for SU.,

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athough I dont involve myself in textures heavilyā€¦

I did buy WrapR for one of my team who uses it to link with Substance Painter successfully

Unfortunately Iā€™m on a MacBook Pro, so doesnā€™t sound like WrapR would work for me :sob:

I guess what I canā€™t figure out is how to break the model down into parts/groups/components once itā€™s in Substance Painter. Is there really no way to have this happen automatically in the export?

Looks like itā€™s only available for windows : (

Based on the feedback provided above, am I just out of options?

You might want to check our chipp Walters YouTube also he posts to this forum, he has a route from SU via Blender I think.

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Just found this going through the Substance Painter forums:

https://forum.allegorithmic.com/index.php/topic,6967.msg33914/highlight,sketchup.html#msg33914

Gonna give it a shot and try looking up Chipp Walters as well

I tried the smart UV unwrap feature in Blender following the instructions from this tutorial: https://www.youtube.com/watch?v=scPSP_U858k

and it got me a uv map that looks like thisā€¦

I feel like this isnā€™t what I need, right? Itā€™s like itā€™s only selecting one of the over 1000 meshes I have, even though I have them all selected?

Canā€™t even follow the directions from the one guyā€™s suggestions because step 2 is to use the BlendUp extension to import into Blender, but the BlendUp plugin isnā€™t available (even for purchase) anymore?

Apparently I just need to try it as a dae file according to this other posting https://forums.sketchup.com/t/blendup-to-sketchup-urgent-advise/71562

Okay, I think I figured out how to do it one ā€œgroupā€ at a time. Hereā€™s the structures brick facade:

Problem it I have hundreds of groups:

Am I going to have to basically explode all of my groups (and basically make my SU model unworkable) and then group by material only to make this work?

I think so, when Iā€™ve been looking at it that what I concluded.I guess its setting up the model for rendering.
Iā€™ll explain how I currently set my model workflow up as background.

I tend to keep a single master model file that I texture as I go, even though I might be generating NPR renders initially, I still texture hi-res for with my VRay materials as part of my workflow, it saves me a lot of time to texture as I go - it makes my model files large but I have a machine that can handle that.


design model file (rendered through SketchFX)

When the design is 95% finalised, I fork the master model file as a master_RENDER file to which I add all the context vegetation and model detail that is extraneous to the general design model - then the files get very large.


same textures as design model file but some veg added (rendered through Vray)

I has been thinking as part of a future Substance integrated workflow, at this point I would re-organise the model around UV groupings and islands. It doesnā€™t have to be by actual material but by logical islands i.e. ā€˜exterior wallsā€™ unwrap and islands, ā€˜Roofā€™ unwrap and islands. There are lots of general UV unwrap videos on Youtube to help you get thinking about UV islands. There are a particularly good suite of Videos from Richard Yot, ā€œStrategies for UV mapping organic meshesā€ (not Sketchup related as its Modo but he is excellent at explaining his methods and why) - you gotta pay for the suite but its only about 29 dollars or so and there is a section on hard surface unwraps.

Ultimately, you have to think about the requirements of the workflow, for (my) architectural stuff, I would say maybe 10-15% (being generous) actually needs to be, or I would want to, texture using Painter, most stuff is flat, new, camera position is far enough away and can be handled using decent sized tileable maps (in the above examples probably 40 percent of the textures were created in Substance Designer and the map outputs created used in Vray materials and applied in SU with standard SU and Vray mapping tools - didnā€™t need to touch Painter.

Also need to consider implications of changes. If the model is changed, I think you would have to re-unwrap that component go back into Painter, repaint stuff, re-generate the maps etc. So again, depends on the output you want

Also bear in mind, the Painter bit of it, Iā€™ve only theorised, Im hoping to find time over the Holiday period to work on it.

Just as an addendum: The design model file size for the example above is 435Mb. The Render_Master model file is 760Mb. Most of this file size is attributable to the texture maps. Many maps are 2k but there are a lot of 4k Maps in there too, some even larger, particularly where I have large tilleable areas, the paving slabs are are large (pixel size) set of maps as is the brickwork where the pixel size can overcome seeing repeatable patterns within a particular shot.

Some updates:

For some reason now if I try to export my SKetchup file as Dae and upload it directly into Substance Designer I get the following error code:
53%20PM

I guess the change is that itā€™s no longer saying anything about missing UVs, but ā€œexpected different index count in <p< elementā€. Anyone have any idea what that means?

hereā€™s the link to the Dae file (too big to upload directly)

hereā€™s the material folder that is generated along with it when exporting Dae from SU

Iā€™ve been emailing back and forth with the SketchFab folks a bit and they suggested I do the following:

So I imported a glTF file of the SU model that had been uploaded to SF into Blender. The result looks like this:

not sure why, but I canā€™t view the texture UV map when I try in blender thoughā€¦ but it seems to work if you look at what shows up in Substance Painter below

Something a little wonky with the faces, but it works. Then I selected all (press A), space bar, manually type in ā€œsmart uv unwrapā€, and create a UV unwrap for the whole thing all at the same time.

Then export from blender as Dae and import the dae. file into Substance Painter and SUCCESS the model imports! Remember to delete the starting cube from blender or else the import will fail.

The result looks like this:

Since Iā€™m never to SP Iā€™m still trying to figure out how to select specific meshes to apply my texture made in substance designer, but I wanted to provide some form of update.

  1. anyone have any idea how to get those weird faces sticking out of the exterior to go away?
  2. anyone have any idea how to select individual groups/meshes in this?

So hereā€™s what happens when I try to apply my texture from Substance designer to the imported model in Substance Painter:

throws computer out of the window

Someone please give me some direction here. The meshes arenā€™t separated. The Texture isnā€™t working. Iā€™ve basically been doing this and nothing else for the past 4 days. I really gotta figure out how to get this thing to work

From what I understand, its ALL about the unwrap and then the subsequent back and forth workflow. If you donā€™t got a good unwrap and therefore good UVā€™s, you are where you are now. SU is probably about the worst in terms of UV handling so you need an intermediate step. No silver bullet Iā€™m afraid. There is no way that trying to do the whole mesh at once is gonna work.
Honestly, look at the Richard Yot video, he does like a whole 2hours 52 minute video on hard surface strategies.
I donā€™t think anyone has done this with SU and Substance yet, particularly on the Mac side, so this is frontier stuff currently I think.Iā€™m hoping to have a better direction after the holiday period.

cheers
rob

Welp, Iā€™m now posting this in the Blender forums. Maybe someone there has a workaround?

I read a dozen or so posts that danced around needing to ā€œsmart UV projectā€ multiple objects/groups simultaneously, yet individually. I think thereā€™s a way, might involve texture atlasing?

Between the SketchUp, Allegorithmic, SketchFab, AND Blender forums, thereā€™s got to be a way to solve this problem.

I have no idea. Pray for me? Sacrifice a small child to the computer gods on my behalf? Losing my mind here.

That tutorial cost $30.00. Itā€™s also for a program called Modo, which Iā€™ve never used (and costs nearly $2,000 to purchase). You really think it will solve my problems?

No.
I meant itā€™s worth the 30 dollars for the video because itā€™s extremely useful in terms of explaining things about UV islands and unwrapping and strategies for for doing so (regardless of the application) and helped my understanding of things that are simply missing from other UV Unwrapping videos. Thatā€™s all.

Somehow, you need to establish a UV map for use in painter, you also need to create those UV map(s) in a logical, practical way that allows you paint the texture maps however you need and somehow get that into back into Sketchup. Doing the whole thing in one go just isnā€™t the way to go and isnā€™t practical.
The video explains how to break any model down, unwrap elements and create strategies to manage the UV island and maps, Richard uses Modo but these are universal concepts and it really helped me understand what I was trying to do and where my initial thinking and understanding of the problem were flawed.
I still havenā€™t sorted it out due to time constraints but I think I know where to start.

There may be way using sketchUV or thrupaint as these plugins (certainly sketchUV) allow you to with limited flexibility, define Uvā€™sfor an object, save, export and import UVā€™s from/to Sketchup.

tried using a .Dae file exported directly from SketchUp into Blender, using the select all -> Smart UV Project -> export as .dae. -> import into Substance Painter and Iā€™m getting basically the same result as I was getting from the SketchFab import into blender strategy, except the model seems to be a little sharper in the SU->Blender->SP version. Also the component functions in the windows seems to be intact as you can see in the GIF. When I paint over one of them, it paints over all of them.

Strange that non of the metal textures seems to be painting onā€¦

Still open to (read: desperate for) suggestions!

Okay, may have made some progress. When uploading the .Dae file from Blender into SP, deselecting the ā€œcreate a texture set per udim tileā€ resulted in a model with a different UV image layer that shows all of my textures in the texture set list in the upper right hand corner. Now I just need to figure out how to auto convert those to layers or something so that I can apply textures to the entire group/component without texturing other parts of the model at the same time