Tiling Technique in Maya and Unreal Question

apollo580

Hello,

I'm working on learning to create modular environments using the tiling technique and picked up "Advanced Tiling Techniques for Environmental Design" by Alex Senechal. This tutorial is good but it doesn't go into details in a few areas that I need help with. I understand the general concept that I bake out several trim sheets with different designs and materials and then UV my model so that the polygons are on the places that I want. 

In the first few videos he goes into blending a tiling texture and a trim sheet detail using 3DS max, box UV with channel 2. Since I'm using Maya LT I dont have this exact option. I have the Hypershade window so I'm able to assign different materials to different polygons but I cant blend them. For example if I wanted a "painted red metal" tiling texture as a base and then a panel opening detail from a trim sheet, how can I blend them in maya or unreal for that matter?

I tried looking online but most tutorials and explanations dont really do blending, it seems they use their trim sheets exclusively and dont do blending. Additionally this method relies on material ID's from what I can tell? So in Unreal I would import my model with different material ID's and assign the trim sheet I want to use to each part, is that correct?

Thank you for any help!

Axi5

Is that box projection of UV's or blended box?

m4dcow

Although I haven't seen the the tutorial I do see that in the description it mentions using 2 UV channels. So I assume the workflow is making a a UV channel where you want you details and trims to be, and then there is another UV channel which isn't cut up as much (or he might use the one generated in UE4). In maya, you can specify textures use a certain UV channel
https://knowledge.autodesk.com/support/maya-lt/learn-explore/caas/CloudHelp/cloudhelp/2015/ENU/MayaLT/files/UV-sets-Assign-a-texture-to-a-UV-set-htm.html
Then you would build a shader network that blends the detail/trim onto the base texture using the alpha of the detail/trim. Now i find this easier to do in UE4, and if that is your target the maya shader network wouldn't carry over, but you would sort of have to "imagine" a red base or whatever since you would only be arranging your detail/trim sheet.

In UE4, to assign a texture to a different UV channel you need a TextureCoordinate node and change the coordinate index to map to different UV channels. So you would do the same sort of thing I described for the maya shader network, blending the maps in the shader before the final output.

Some things to note:

• This method wouldn't use multiple material IDs, since it relies on the blending to be done in a single material.
• UE4 has the 2nd UV channel (coordinate index 1) typically reserved for lightmaps and you may have issues with it deleting your UV channel on import depending on your import settings.
• There are issues normal maps in UE4 in any other UV channel than the first (coordinate index 0) where they don't work as intended since tangents are only calculated for the first channel for performance reasons. So i'm not sure if the tutorial goes into fixing that issue.

poopipe

I believe you can force the calculation of tangents for other UV sets in unreal - I've not done it myself but remember reading about it

apollo580

m4dcow said:

Although I haven't seen the the tutorial I do see that in the description it mentions using 2 UV channels. So I assume the workflow is making a a UV channel where you want you details and trims to be, and then there is another UV channel which isn't cut up as much (or he might use the one generated in UE4). In maya, you can specify textures use a certain UV channel
https://knowledge.autodesk.com/support/maya-lt/learn-explore/caas/CloudHelp/cloudhelp/2015/ENU/MayaLT/files/UV-sets-Assign-a-texture-to-a-UV-set-htm.html
Then you would build a shader network that blends the detail/trim onto the base texture using the alpha of the detail/trim. Now i find this easier to do in UE4, and if that is your target the maya shader network wouldn't carry over, but you would sort of have to "imagine" a red base or whatever since you would only be arranging your detail/trim sheet.

In UE4, to assign a texture to a different UV channel you need a TextureCoordinate node and change the coordinate index to map to different UV channels. So you would do the same sort of thing I described for the maya shader network, blending the maps in the shader before the final output.

Some things to note:

• This method wouldn't use multiple material IDs, since it relies on the blending to be done in a single material.
• UE4 has the 2nd UV channel (coordinate index 1) typically reserved for lightmaps and you may have issues with it deleting your UV channel on import depending on your import settings.
• There are issues normal maps in UE4 in any other UV channel than the first (coordinate index 0) where they don't work as intended since tangents are only calculated for the first channel for performance reasons. So i'm not sure if the tutorial goes into fixing that issue.

Thanks for all the advice. What I got out of your post is that it's almost certainly easier and a better practice to have a trim sheet have all the details I need and just map it out onto 1 UV channel? And reserve the second UV channel for Unreals lightmap baking?

m4dcow

apollo580 said:

m4dcow said:

Although I haven't seen the the tutorial I do see that in the description it mentions using 2 UV channels. So I assume the workflow is making a a UV channel where you want you details and trims to be, and then there is another UV channel which isn't cut up as much (or he might use the one generated in UE4). In maya, you can specify textures use a certain UV channel
https://knowledge.autodesk.com/support/maya-lt/learn-explore/caas/CloudHelp/cloudhelp/2015/ENU/MayaLT/files/UV-sets-Assign-a-texture-to-a-UV-set-htm.html
Then you would build a shader network that blends the detail/trim onto the base texture using the alpha of the detail/trim. Now i find this easier to do in UE4, and if that is your target the maya shader network wouldn't carry over, but you would sort of have to "imagine" a red base or whatever since you would only be arranging your detail/trim sheet.

In UE4, to assign a texture to a different UV channel you need a TextureCoordinate node and change the coordinate index to map to different UV channels. So you would do the same sort of thing I described for the maya shader network, blending the maps in the shader before the final output.

Some things to note:

• This method wouldn't use multiple material IDs, since it relies on the blending to be done in a single material.
• UE4 has the 2nd UV channel (coordinate index 1) typically reserved for lightmaps and you may have issues with it deleting your UV channel on import depending on your import settings.
• There are issues normal maps in UE4 in any other UV channel than the first (coordinate index 0) where they don't work as intended since tangents are only calculated for the first channel for performance reasons. So i'm not sure if the tutorial goes into fixing that issue.

Thanks for all the advice. What I got out of your post is that it's almost certainly easier and a better practice to have a trim sheet have all the details I need and just map it out onto 1 UV channel? And reserve the second UV channel for Unreals lightmap baking?

Sort of, if the tutorial addresses I mention it could be worth using that technique, but personally I think unreal's deferred decal materials workflow is an easier workflow, so you could look into that.

apollo580

m4dcow said:

apollo580 said:

m4dcow said:

Although I haven't seen the the tutorial I do see that in the description it mentions using 2 UV channels. So I assume the workflow is making a a UV channel where you want you details and trims to be, and then there is another UV channel which isn't cut up as much (or he might use the one generated in UE4). In maya, you can specify textures use a certain UV channel
https://knowledge.autodesk.com/support/maya-lt/learn-explore/caas/CloudHelp/cloudhelp/2015/ENU/MayaLT/files/UV-sets-Assign-a-texture-to-a-UV-set-htm.html
Then you would build a shader network that blends the detail/trim onto the base texture using the alpha of the detail/trim. Now i find this easier to do in UE4, and if that is your target the maya shader network wouldn't carry over, but you would sort of have to "imagine" a red base or whatever since you would only be arranging your detail/trim sheet.

In UE4, to assign a texture to a different UV channel you need a TextureCoordinate node and change the coordinate index to map to different UV channels. So you would do the same sort of thing I described for the maya shader network, blending the maps in the shader before the final output.

Some things to note:

• This method wouldn't use multiple material IDs, since it relies on the blending to be done in a single material.
• UE4 has the 2nd UV channel (coordinate index 1) typically reserved for lightmaps and you may have issues with it deleting your UV channel on import depending on your import settings.
• There are issues normal maps in UE4 in any other UV channel than the first (coordinate index 0) where they don't work as intended since tangents are only calculated for the first channel for performance reasons. So i'm not sure if the tutorial goes into fixing that issue.

Thanks for all the advice. What I got out of your post is that it's almost certainly easier and a better practice to have a trim sheet have all the details I need and just map it out onto 1 UV channel? And reserve the second UV channel for Unreals lightmap baking?

Sort of, if the tutorial addresses I mention it could be worth using that technique, but personally I think unreal's deferred decal materials workflow is an easier workflow, so you could look into that.

Okay cool! Thanks for the input, I'll check it out