Trim Sheet help required !

MamdouhFahmy · May 29 2025

Hello ,Kindly i need help with this one I am working an ornamental door as part of my trim sheet exercise " this is my first one " so am figuring out stuff while working , i know i need to have my textures tile from left to right and make the uvs match , so if you take a look at the attached image the upper left corner of the door it has this shape which makes an aweful distortion to the uvs when flattened straight , any tips on how to handle shapes like this when trying to lay them out for trims .

Fabi_G · May 29 2025

Hi! If UVs are straightened and even, the mesh topology should pretty even as well (as much as possible). Just take one segment, move the UV vertices and observe the checker texture on the mesh changing. I recommend a cleaner model in general with the more even topology/faces. If you have a tiling texture, you can have fewer strips extending the 0-1 space.

Image: https://us.v-cdn.net/5021068/uploads/editor/y8/l8zlnw3gczsj.png

Benjammin · May 29 2025

You're always going to have some distortion when flat things are bent around curves like that, but what it looks like depends on the kind of detail - ie: horizontal lines (relative to your trim sheet) will be mostly ok, vertical lines not so much.
I would do a rough version of the trim texture and see how it looks on a triangulated version of your mesh (looking at it with quads isn't going to show you true distortion).

MamdouhFahmy · May 30 2025

Fabi_G said:

Hi! If UVs are straightened and even, the mesh topology should pretty even as well (as much as possible). Just take one segment, move the UV vertices and observe the checker texture on the mesh changing. I recommend a cleaner model in general with the more even topology/faces. If you have a tiling texture, you can have fewer strips extending the 0-1 space.

Thats good advice i will make the topology cleaner and see if its fixed

MamdouhFahmy · May 30 2025

Benjammin said:

You're always going to have some distortion when flat things are bent around curves like that, but what it looks like depends on the kind of detail - ie: horizontal lines (relative to your trim sheet) will be mostly ok, vertical lines not so much.
I would do a rough version of the trim texture and see how it looks on a triangulated version of your mesh (looking at it with quads isn't going to show you true distortion).

Does it make a difference if the mesh is triangulated instead of being quads with the uvs ! , the trim thats supposed to cover that area is ornamental details like flower shapes and stuff so i think distortion going to be very obvious but i do need to do a rough texture and see how it works thanks ^^

dimwalker · May 30 2025

MamdouhFahmy said:
Does it make a difference if the mesh is triangulated instead of being quads with the uvs ! , the trim thats supposed to cover that area is ornamental details like flower shapes and stuff so i think distortion going to be very obvious but i do need to do a rough texture and see how it works thanks ^^

Yes, triangulation will make it super inconvenient to select loops.

poopipe · May 30 2025

it makes it inconvenient but as stated above you'll get a more accurate idea of what the distortion will look like on the final asset.

uv interpolation is a dumb linear operation and edge orientation can make a pretty significant difference when a quad deviates from a 1:1 aspect ratio

to counter distortion, add geometry. the more regular (ie. square) your triangles are, the less wonky things will look

okidoki · May 30 2025

In blender there is the possibilty to maintain texel density (or texel distribution ?) via special UV unwrapping via "Follow Active Quads" and "SmartUV Project".. so the UV's are spaced accordingly to the different length of the faces like so:

Image: https://us.v-cdn.net/5021068/uploads/editor/jh/yk1d63ma37e6.jpg

So i'm guessing there is something similar in whatever 3D software is used ??

Of course "contructing this" with even distribution in 3D in the first place might be a litttle to cumbersome.. ( here trying to regular space the segements via help of the "Loop Tools" (evenly spacing over the whole "curve" would shift the sharp segment borders ))

Image: https://us.v-cdn.net/5021068/uploads/editor/b7/nazirvi7t74q.jpg

Noren · May 30 2025

This might be software or even viewport driver dependent, but at least in 3ds max, you'll always see the distortion of the individual underlying triangles (at least that was always my assumption and how I handled it). The main problem aside from the UV skewing is when the triangulation changes down the line.

In this case, you are basically exchanging texture space for polygons, and since you already have a pretty high polycount to define the shapes, you might as well go a bit higher for smoother texture deformation like was mentioned.

Fabi_G basically already said it, and having a more even topology from the start (with sections as orthogonal to the path of the trim as possible) is a good idea and makes things a lot easier, but just to be clear: Even with trims, your UVs don't have to be all square and even throughout, and you could have much better UVs even with your current geometry. The problem is the mismatch that's especially apparent in the "vertical" distribution of the length-wise loops. And looking at it, it's not even clear if those loops contribute to the shape in the first place. They'll probably help with texture distortion, but in that case, you could simply remove them and add them anew and have a more or less "ideal" (as ideal as it can be) match with your UVs.

But yeah, it's probably a good idea to do a rough test case first to see if this even works well enough with your intended texture.

MamdouhFahmy · May 30 2025

Noren said:

This might be software or even viewport driver dependent, but at least in 3ds max, you'll always see the distortion of the individual underlying triangles (at least that was always my assumption and how I handled it). The main problem aside from the UV skewing is when the triangulation changes down the line.

In this case, you are basically exchanging texture space for polygons, and since you already have a pretty high polycount to define the shapes, you might as well go a bit higher for smoother texture deformation like was mentioned.

Fabi_G basically already said it, and having a more even topology from the start (with sections as orthogonal to the path of the trim as possible) is a good idea and makes things a lot easier, but just to be clear: Even with trims, your UVs don't have to be all square and even throughout, and you could have much better UVs even with your current geometry. The problem is the mismatch that's especially apparent in the "vertical" distribution of the length-wise loops. And looking at it, it's not even clear if those loops contribute to the shape in the first place. They'll probably help with texture distortion, but in that case, you could simply remove them and add them anew and have a more or less "ideal" (as ideal as it can be) match with your UVs.

But yeah, it's probably a good idea to do a rough test case first to see if this even works well enough with your intended texture.

I was about to start tweaking the topology and see if it fix it and i saw that the other piece below it has the same shape & much cleaner topology so i unwraped it quickly to test and yes you both are right its way way better & almost no distortion so now am going to apply that to the original shape , thanks .

MamdouhFahmy · May 30 2025

okidoki said:

In blender there is the possibilty to maintain texel density (or texel distribution ?) via special UV unwrapping via "Follow Active Quads" and "SmartUV Project".. so the UV's are spaced accordingly to the different length of the faces like so:

So i'm guessing there is something similar in whatever 3D software is used ??

Of course "contructing this" with even distribution in 3D in the first place might be a litttle to cumbersome.. ( here trying to regular space the segements via help of the "Loop Tools" (evenly spacing over the whole "curve" would shift the sharp segment borders ))

hey , i guess the equivalent to that in maya would be unfold along U i tried it but didnt help , i tested the uvs on a cleaner topology that has the same shape just below it and it way better , so yeah i need tweak the topology make it cleaner , thanks for your efforts & break down

Eric Chadwick · May 30 2025

Instead of using Attach File

Image: https://us.v-cdn.net/5021068/uploads/editor/fl/hu07nlek6j2b.jpg

, you should embed your images with Attach Image

. Or even better, just drag-and-drop right into your post. This makes it easier for people to see your images, they don't need to click the attachments.

MamdouhFahmy · May 31 2025

Eric Chadwick said:

Instead of using Attach File , you should embed your images with Attach Image . Or even better, just drag-and-drop right into your post. This makes it easier for people to see your images, they don't need to click the attachments.

I will thanks for the info ^^

MamdouhFahmy · Jun 3 2025

I got an update on the trim , i am working on texel density 2k for 2 meters which is in maya supposed to be 10.24 px/unite but i came across another problem , my understanding is the better way to do trim is to finish the model first to measure accurately its texel density across the uv area which is what i did but the thing is when i followed the rule 100% the area which a trim takes is very small and that resulted in pixelated heightmap in substance desiger, is thats not the way i should do trim ! how do you solve this problem , i also attached an image to the door am trying to make so you get the full picture.

Image: https://us.v-cdn.net/5021068/uploads/editor/nn/mg3hb2iv6q5z.jpg

Image: https://us.v-cdn.net/5021068/uploads/editor/3n/x432t4y0bgfs.jpg

Image: https://us.v-cdn.net/5021068/uploads/editor/n7/uv06p5iyi8dk.jpg

ZacD · Jun 16 2025

Is the resolution actually bad? Looks like any of the problem areas are going to be less than 1 pixel in the final image. Also it looks inverted and too deep to accurately match the reference.

Trim Sheet help required !

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