Texturing inworld without custom UV maps

[Marianne Little]

I hope I am using the correct technical terms here.

I suck in creating texture maps for the meshes I slap together in Blender. I can, however make some tileable textures, and need to repeat them. I am using Planar texture mapping, and it work great on simple, large surfaces. The problem is when I try to make something with a bit of finesse, instead of square parts.

I solve it by assigning materials to different parts, and upload them to SL without custom maps.

The picture below show 2 of my mesh things. Not very well, I can take closeups later, or send anyone an example.

The garden pond is a square with cut corners. I had to use all 8 materials on the planes. Even if I use Planar, they are a nightmare to align.

The garden wall is a copy of the mole made LH walls for Victorian homes. The original part is lovely of course, but small. Using the parts to build 32 m adds up a lot. So I made a 32 m wall and is using the mole made columns. The brick and top is something I tried to make from taking pictures of the wall and making seamless ones. It looks good from a distance, but not so good on a closer look. The top part is not a flat prim, but curved.

Is it a simpler way I can use Default inworld, and not get distorted textures?

 

[Marianne Little]

I hope this show the problem better.

1: Uploaded with materials. I have selected the objects and "applied all transforms" and is using "SL - open sim static" when I export it.

2: I apply a grid texture as planar and use align planar faces. It looks like I can texture it without problems.

3: But I apply a stone texture, and the edges must have the texture rotated in a 45 degrees. Because even if the grid came on correct, the stone texture did not. A mess.

This is why I need so many materials, I must manually adjust and adjust all faces.

 

[ChinRey]

3 hours ago, Marianne Little said:

I suck in creating texture maps for the meshes I slap together in Blender. I can, however make some tileable textures, and need to repeat them. I am using Planar texture mapping, and it work great on simple, large surfaces.

Yes, planar usually works well on simple square surfaces but it doesn't take much deviation before you get into trouble. There's one thing that's not clear from your post: are these meshes UV mapped at all?

Btw, I know you're an experienced prim builder and one workaround for objects as simple as these would be to build a prim draft, get all the textures right in an environment you're familiar with, export with Firestorm's dae export function and clean up in Blender without touching the UV maps there at all. You would have to sue default texture mapping for the draft though, planar mapping does not export.

Edited April 28, 2023 by ChinRey

[ChinRey]

1 hour ago, Marianne Little said:

3: But I apply a stone texture, and the edges must have the texture rotated in a 45 degrees. Because even if the grid came on correct, the stone texture did not. A mess.

If you look closely at the two vertical surfaces closest to the camera, you'll notice their UV mappings are rotated 180 degrees relative to each other. It's hard to see on the very symmetrical grid texture but very obvious with the looser stone texture.

Edited April 28, 2023 by ChinRey

[Marianne Little]

7 minutes ago, ChinRey said:

Yes, planar usually works well on simple square surfaces but it doesn't take much deviation before you get into trouble. There's one thing that's not clear from your post: are these meshes UV mapped at all?

I can assign materials (Put on differnt colors on faces in edit mode). I know the steps to UV editing. I have managed to export UV maps, but I have not liked the result when I try to texture them. I do not have photoshop, and try with the free Krita.

When I will try inworld editing with simple textures, I only assign materials and export the mesh. I have not made an UV map.

You mean I must make an UV map, no matter what?

[Marianne Little]

11 minutes ago, ChinRey said:

If you look closely at the two vertical surfaces closest to the camera, you'll notice their UV mappings are rotated 180 degrees relative to each other. It's hard to see on the very symmetrical grid texture but very obvious with the looser stone texture.

Can I rotate the faces so they run parallel around the item? As it is now, it is clear that the cut corner faces are not aligned with the longer sides.

And how do I know they are rotated right? I can not see it in blender.

Can I put on a texture in blender, so I can see one face is correct and the other is rotated a differnt way?

Uff. I am so lost. Textures are hard.

[Aquila Kytori]

10 hours ago, Marianne Little said:

You mean I must make an UV map, no matter what?

It will make texturing easier if you do because then it will be you that controls how the image texture you assign to the different parts of the model are mapped to the mesh.

The fewer UV seams your mesh has often means fewer UV islands to deal with and so less problem with aligning textures later on.

For example in the image above if you could unwrap the top part of the mesh, the part above the side walls (these are called coping stones in English) as a single straight UV island wouldn't that make texturing in SL easier ?

 

The following may seem a bit complicated but try taking it slowly step by step and you may find its the way to go.

So starting with our base model:  Note that I have removed any surfaces that wont gererally be seen like the underside faces of the coping stones because doing this means less UV seams to mark and less UV islands to deal with.

The pond is one object in Blender In the following 3 images I have duplicated then separated the parts of the pond to try and better show where the UV seams are placed. Don't you do this

 

Marking seams, The aim here is to get the parts to unwrap in straight lines and with as few uv islands as possible. The coping stones have one edge loop where all 3 edges are marked as seams but the rest only have the two edges marked as seams.This will ensure that it unwraps as a single straight uv island:

 

the UV seams:

 

Adding the built into Blender Color Grid image texture to the model so that after UV unwrapping we can see how this grid texture is mapped to the mesh :

 

Unwrapping the Pond model :

 

Rotate the UV islands as needed so that a horizontally aligned texture will be correct on the mesh.

The 2D cursor will be used as the scaling point later. Constrain to Image Bounds is enabled because it makes it very easy to drag the UV islands all to the same "stating point" before scaling.

Setting up the UV Editor before editing the UV islands. By default the 2D Cursor will be at X = 0.0 and Y = 0.0 in the UV space (bottom left hand corner of the 0 to 1 UV space).

 

Grab each UV island , one at a time and drag down towards to bottom right hand corner. The lower edge of each uv island should be on the lower edge of the UV space.

Don't forget to uncheck the Constrain to Bounds !

 

Open the Color Grid image in the UV Editor:

 

In the UV editor change the pivot point to be the 2D Cursor.

In the 3D viewport change the shading to Material Preview so that we can see the Color grid texture on the model.

Then in the 3D viewport select all of the mesh, go to the UV Editor and scale all the UV's up quite alot.

 The exact amount of scaling is not that important, its just to be able to see more clearly how the texture is mapped to the mesh. You can later scale up or down again or leave as is and use the scale options when applying a texture in SL

 

A little more editing in the UV editor:

 

Zoom in to see how now edges are aligned across the coping stone part of the mesh:

 

Last step is to add and assign the different parts of the model their own Materials :

 

If you need to see more clearly where the UV seams have been placed you can download the .blend file here :  https://litter.catbox.moe/u5hke9.blend

Edited April 28, 2023 by Aquila Kytori

[ChinRey]

3 hours ago, Marianne Little said:

Can I put on a texture in blender, so I can see one face is correct and the other is rotated a differnt way?

You can as Aquila demonstrated. Me, I'm usually too lazy for that. Most of the time I simply triangulate an unclear surface temporarily to see which way is up. Take this for example (UV map to the left, mesh model to the right):

 

You can't see which way the UV map is rotated here of course but look at only one triangle:

and it's clear as ink.

Edit:

I think I should comment on this because Aquila makes a very important point that is far to often missed:

2 hours ago, Aquila Kytori said:

Rotate the UV islands as needed so that a horizontally aligned texture will be correct on the mesh...

Let's make this absolutely clear:

Blender does not make good UV maps automatically!!!

Back when Klytyna was active on the forums, she kept talking about Blender's auto-bakefail and that's a very good word for it. Blender can give you a good starting point but you have to be prepared to do some manual editing if you want a decent result.

Edited April 28, 2023 by ChinRey

[Aquila Kytori]

51 minutes ago, ChinRey said:

1 hour ago, Aquila Kytori said:

Rote the UV islands as needed so that a horizontally aligned texture will be correct on the mesh...

Too lat to use Blenders built in Color Grid !   Too lat to correct my typo !   and now too lat to even do a little UV editing !  

 

Edited April 28, 2023 by Aquila Kytori

[ChinRey]

25 minutes ago, Aquila Kytori said:

Too late to correct my typo !

Not at all! 🙂

[Marianne Little]

Sorry for disappearing in 6 hours. RL kept me so busy.

I must read very carefully tomorrow. Texturing is hard. I have to try again.

 

Amazing what people make out of mesh. I am happy if I can line up a texture.

Edited April 28, 2023 by Marianne Little

[Wulfie Reanimator]

I wish I could get online to take some screenshots to demonstrate the (expected) weirdness that happens with planar mapping and "misaligned" faces.

An easy-to-examine example would be a simple mesh cylinder. See how the different facets warp the texture with the face angle.