Model Building

[Quarrel Kukulcan]

9 hours ago, IvyTechEngineer said:

I used Photoshop and paint.net to merge the two sides of the coin and that worked ok. Photoshop was used to crop the images and paint,net was used to merge all the images together into a single image.

That is a perfectly valid method.

Quote

Thanks, I wanted to minimize the cost (i know that is lame) but thought if I could create a single texture that it would be better. When you upload a model the Include Textures can be selected as well and somehow SL knows what texture needs to be uploaded. Maybe that info is embedded in the DAE file?

Using fewer textures means both a lower upload cost and better performance for everyone seeing your object. It's a win/win.

Your texture image files don't need to match the .dae file name but they do have to be in the same directory or the SL uploader won't find them. It also only works for the diffuse textures, not the normal or specular textures (and Blender doesn't use compatible specular maps anyway).

[IvyTechEngineer]

19 hours ago, Fluffy Sharkfin said:

Just wanted to add since I mentioned normal maps, etc. you could also look into using one of several tools available to generate depth and cavity maps for the coin texture which you could then use to create the normal and specular maps needed for SL materials.

Anyway, it would be a really nice touch, but it's best to stick to mastering the basics first, especially when it comes to sensible texture resolutions based on object size, because as nice and shiny as those coins may look with 3 high resolution 1024 x 1024 textures on your creative efforts will most certainly draw the ire of others. 😄

Thanks, I had thought about doing something like that but was unsure what tools I could use. I would use a CAD program to add some 3D to the image maybe but maybe there is something "free" that I could use. The coin looks nice in SL but of course the lighting is wrong.

[IvyTechEngineer]

14 hours ago, arton Rotaru said:

You can do all that in PS easily. What I would do is resizing the images to 128x128 (Bilinear). Create a new image with the size of 128x256. Ctrl-A > Ctrl-C > Ctrl-V into the new image. Move one up, and one down (hold Shift to keep it in the middle). Merge the layers (Ctrl-E). Add some padding by duplicating the layer. Move it below the original layer and give it some gaussian blur. Copy the blurred layer several times until you have something like this.

Activate the background layer and save as Targa 24 bits/pixel.

 

I do have access to Photoshop and it would work I am sure. Thanks

[IvyTechEngineer]

8 hours ago, Fluffy Sharkfin said:

I was just extolling the virtues of the Local Textures feature which you can (and should) learn more about from this wiki page  

I will check it out. Thanks

[IvyTechEngineer]

6 hours ago, Quarrel Kukulcan said:

That is a perfectly valid method.

Using fewer textures means both a lower upload cost and better performance for everyone seeing your object. It's a win/win.

Your texture image files don't need to match the .dae file name but they do have to be in the same directory or the SL uploader won't find them. It also only works for the diffuse textures, not the normal or specular textures (and Blender doesn't use compatible specular maps anyway).

Thanks, I am not sure I totally understand how to improve the quality and realism of my coin.  I am really a CAD designer with just a very small amount of artistic flare, lol but thanks for your advice.

[Fluffy Sharkfin]

15 minutes ago, IvyTechEngineer said:

Thanks, I had thought about doing something like that but was unsure what tools I could use. I would use a CAD program to add some 3D to the image maybe but maybe there is something "free" that I could use. The coin looks nice in SL but of course the lighting is wrong.

It's a subject that has probably been brought up more than once on these forums, for instance this thread

is quite recent and has a handy link in the final post to an open source tool for generating depth maps, etc.

[IvyTechEngineer]

3 minutes ago, Fluffy Sharkfin said:

It's a subject that has probably been brought up more than once on these forums, for instance this thread

is quite recent and has a handy link in the final post to an open source tool for generating depth maps, etc.

So what software should I use in the future? 

[Fluffy Sharkfin]

2 minutes ago, IvyTechEngineer said:

So what software should I use in the future? 

Whichever software you're most comfortable with.  As I said in my previous post there's a link to an open source tool in the thread I mentioned, and there are other similar tools available that you can try.

In the end though it's really a matter of trial, error and personal preference, there is no singular piece of software that you should use.  If you use search and read through a few threads on these forums you'll find plenty of helpful hints and suggestions on how to improve your mesh and texture creation process.

[IvyTechEngineer]

Anyone build wires in SL? I am working on a DC Motor model that I want to connect to a 12V battery and turn on and off the spinning of the motor with a script. 

[arton Rotaru]

3 hours ago, IvyTechEngineer said:

Anyone build wires in SL? I am working on a DC Motor model that I want to connect to a 12V battery and turn on and off the spinning of the motor with a script. 

I got away with wires with a rectangular cross section on this. For thin wires like this, a triangular cross section would work good enough as well. For thicker wires I would try with more sides, though.

Edited January 20, 2022 by arton Rotaru

[IvyTechEngineer]

4 hours ago, arton Rotaru said:

I got away with wires with a rectangular cross section on this. For thin wires like this, a triangular cross section would work good enough as well. For thicker wires I would try with more sides, though.

This is very nice. Did you build this in Blender or in Second Life or somewhere else?

[arton Rotaru]

47 minutes ago, IvyTechEngineer said:

This is very nice. Did you build this in Blender or in Second Life or somewhere else?

I made this in 3ds Max. Which doesn't matter much. Can be done in Blender likewise. It's the innards of my Useless Box. 😁

Forgot to say, this is all baked down from highpoly to lowpoly meshes. Which helps to make the rectangular cross section wires appear more round. In general, wires and cables are usually done with splines/curves in 3D modeling programs.

[IvyTechEngineer]

16 hours ago, arton Rotaru said:

I made this in 3ds Max. Which doesn't matter much. Can be done in Blender likewise. It's the innards of my Useless Box. 😁

Forgot to say, this is all baked down from highpoly to lowpoly meshes. Which helps to make the rectangular cross section wires appear more round. In general, wires and cables are usually done with splines/curves in 3D modeling programs.

Wow, that is so cool. I would love to study what you have done in more detail. 

[arton Rotaru]

2 hours ago, IvyTechEngineer said:

Wow, that is so cool. I would love to study what you have done in more detail. 

Well, nothing special actually. Creating the highpoly meshes. Creating the lowpoly meshes. Exploding both for baking purposes with a cage.

Offsetting the pivot by adding an extra triangle for the rotating parts.

Creating the LOD models.

 

The whole action is just hardcoded values for llSetLinkPrimitiveParamsFast calls in a timer event.

[IvyTechEngineer]

arton Rotaru, this is exactly the stuff I want to learn about. I teach electrical and mechanical engineering and we use Solidworks for CAD and Arduinos for some of our projects. I am new to Blender really and just figuring some stuff our with how to texture objects, lol. I am also new to writing LSL scripts. I do have the Heaton books and have watched a lot of YouTube videos. It has been a struggle because I don't believe there are very many people still active in SL with the have the breath of knowledge needed to do the kind of things you have done.  

Thanks for your advise.

OBTW, I just bought your Useless Box and looked around your SL Marketplace store, nice stuff!

[arton Rotaru]

9 minutes ago, IvyTechEngineer said:

It has been a struggle because I don't believe there are very many people still active in SL with the have the breath of knowledge needed to do the kind of things you have done.

Ah well, I think there are still quite a few people left, and possibly there are still new people who learned how to do things in SL. Especially when you look into the scripting section of this forums, there are still some incredibly skilled and, knowleged Residents around.

Furthermore, not all creators in SL are willing to share their knowledge. After all it's tough competition on the marketplace.

However, it's a process that takes time. At the time I had build the box, I was already 7 years in SL. 7 years of learning something new every day. Now,  another  7 years later, I would build the box most likely in a much different way, because it's another 7 years of experience.

What I realized early on, when I started creating in SL, was that I had to learn LSL scripting, because in the end, pretty much everything you make, requires a script in one way or another. And most often, you need those scripts tailored specifically for the project you are working on. The way I learned LSL was basically by editing existing scripts. After a year of doing that, I started writing my first script entirely from scratch.
When I'm tired of modeling/texturing, I'm happy when I can spend time doing the scripts now.

Taking your time, mastering one thing after the other is the way to go.

 

[IvyTechEngineer]

Hello,

Ok so I have added some cables to my DC motor model. The parts of the model I want to connect to in SL were linked together inworld and saved as a single DAE file to maintain spatial relationships. Then I added 4 cables in blender, but each cable only had two handles so I had to subdivide them in Blender.

https://pasteall.org/blend/4e617f9018e747b0b6fc0bff2e53b9f6

You also need to convert each cable to meshes before you can texture them. The mesh models of the cables are larger than I like. Without mesh reduction one cable (with joined terminations) has:

• Vertices 3,708
• Edges 7,110
• Faces 3,504
• Triangles 6,960

I have been rewatching some YouTube video of mesh reduction using decimation in Blender but the model is just way over defined. Suggestions?

https://pasteall.org/blend/31c3efb3c5694343b8fe04a0779ff8b3

[ChinRey]

2 hours ago, IvyTechEngineer said:

• Vertices 3,708
• Edges 7,110
• Faces 3,504
• Triangles 6,960

I have been rewatching some YouTube video of mesh reduction using decimation in Blender but the model is just way over defined. Suggestions?

It's actually much worse, those figures you give is only for one of the cables, not the whole build.

The numbers for the whole assembly are:

• Vertices 12,792
• Triangles 23,484

(The other two numbers don't matter.)

But for these illustrations I'm using just one cable and one connector merged, starting with 3,582 vertices and 6,936 tris.

First thing is to reduce the curve resolution for those cables. It's 96 which is waaaaaaaaaaaaayyyy too much by any standard:

It's especially unfortunate when it's supposed to meet another component with curve resolution 6:

I'm not sure what curve resolution you want. I would guess 6 (to match that other part) or possibly 8. Certainly no more than 12.

Here it is with 8:

More than 90% of the tris and vertices gone and with smooth normals nobody's ever going to notice the difference.

With curve resolution 6 you get it down even lower:

It still looks more than smooth enough, especially with a dark texture (I suppose that's what you want here):

(Btw, you may want to delete those circles of loose vertices like the one in the background here. The uploader is supposed to delete them for you but you never know and it's always a good practice to keep your meshes clean. This is not only true for SL. In fact SL is far more forgiving when it comes to loose vertices and edges than most 3D platforms are.)

You also want to reduce the number of edge loops around the bends of the cable. I can't give you any specific advice for how much but here I've deleted every other edge loop apart from one section that I kept unhanged. With this and curve resolution around the circumference set to 6, we can cut 3,582 vertices and 6,936 tris down to 168 and 288 respectively and it looks like this:

As a final little touch, get rid of the hidden geometry like the tris marked in red here:

It's a trivial detail compared to the other changes but every little bit helps and besides, keeping them is just poor craftmanship.

For the LOD models you do not want a curve resolution around the circmuference higher than 3 for mid and low and for lowest you should be able to get away with just two face in a V shape like this:

It's possible you can do that with the low LOD model too.

For the LOD models you also want to cut down drastically on the number of edge loops along the cable of course.

Another alternative for hte LOD models is to use an impostor face for them of course but that's a little bit more complicated than simply deleting edge loops.

Edited February 16, 2022 by ChinRey
Typos

[IvyTechEngineer]

Thank you and I agree that I was only focused on one cable. In terms of reducing the mesh I am trying to figure out "how to" do that in Blender. 

[Aquila Kytori]

1 hour ago, IvyTechEngineer said:

In terms of reducing the mesh I am trying to figure out "how to" do that in Blender. 

To reduce from 6912 to 224 tris :

 

1 :    Change the Bezier Curve resolution from 12 to 7 ....

 

2:  Change the Nurbs Circle resolution from 12 to 1 ....

 

3:  Convert the Bezier Curve to mesh. 

    Select unnecessary edge loops and delete them   .......

 

4:  Finally use Edge Slide to smooth out the curve a little more   .......

[ChinRey]

37 minutes ago, Aquila Kytori said:

1 :    Change the Bezier Curve resolution from 12 to 7 ....

 

2:  Change the Nurbs Circle resolution from 12 to 1 ....

 

That's the easiest way to do it but you have to do it before you convert the curve to mesh of course.

But don't despair if it's too late. You can alt-click to select a whole edge loop or line and shift-alt-click to select multiple on a mesh. This way it isn't that extra work and as a bonus, you get to practice the by far most important technique for creating good LOD models.

[IvyTechEngineer]

This is exactly what I needed ... Thanks Aquila and CjinRey 

[IvyTechEngineer]

Sorry, ChinRey

[IvyTechEngineer]

Sorry, a follow up question for you. Thank you for your excellent advise. When I created the texture in Blender and saved it as a image, when I uploaded the model and select "include texture" the texture doesn't look like the uv map texture in Blender. The image is 1024x1024 ... Not sure what is going wrong. Have not had this issue with other models.

[Aquila Kytori]

12 hours ago, IvyTechEngineer said:

when I uploaded the model and select "include texture" the texture doesn't look like the uv map texture in Blender.

The most common cause of this is that the object has more than one UV map. This can result in the wrong UV map being uploaded with the model.

In Edit mode with the model selected click on the Objects Data Properties tab and then under UV maps check if there are more than one UV map listed.

If yes then you have the option to either delete the one(s) you don't want or simply make sure the one you do want is selected (active) before you export.

Don't confuse the selected/active UV map with the little camera icon. The camera icon is only for telling Blender which map to use when rendering .

In the screenshots below there are two UV maps for the model.  UVMap and UVMap001

The first image shows the correct UV map has been selected :

 

The next image shows the incorrect UV map selected  but in the 3D viewport the correct UV map is sill being used because the camera icon for the correct map is still enabled :

 

Next with the other UV maps camera icon enabled we now see the change in the 3D viewport :

 

So before exporting make sure the correct UV map is selected:

 

and in the Collada export options  > Operator presets choose  sl+open sim static.

 

12 hours ago, IvyTechEngineer said:

The image is 1024x1024 ...

On a 1204² texture you seem to be simply painting the insulating part of the wire red and the metal part grey and saving this to use on your wire inworld. ??

Ask yourself if this is a good use of resources?

what other options do you have?

1: Don't create a texture at all.

  In Blender assign the model wire 2 materials, for example : "Plastic" and "metal". Then assign these materials to the appropriate faces of the  model. When the wire is rezzed inworld edit it and from the build floater > Texture > with Select face enabled give the plastic part a red colour then select metal part and give it a grey colour.

Advantage is: no UV unwrapping to do. Don't need to create a texture and upload it and you can change the wire colours when ever you want.

2: UV unwrap and create a much smaller texture.

Because you are just painting pure colours, red for plastic part and grey for metal then you could in theory have a texture size of 1 x 2 pixels. 

In Photoshop or Gimp create a 1 x 2 pixel texture. colour one pixel red and the other grey. save and then bring into Blender as the texture for your wire.

Next in Blender...... select part of your model you want to be red and UV unwrap it ,  U > Unwrap. (No need to mark any seams). In the UV editor select the resultant UV island and scale it down to a single point using S (scale) 0 (zero). Then position the single point collapsed UV's over the red part of the texture. Repeat for the metal part of the wire. Et voila ! your wire is textured exactly the same as you have it now but instead of using a 1024² texture size (1,048576 pixels) you are using a 1 x 2 (2 pixels).

Of course you cant upload such a small texture to SL but you get the idea. Why use a texture when you can create the same effect by giving your model two materials in blender and then assign those two material faces their colour in world using the SL build floater ?

Your model your choices

 

 

 

Edited February 17, 2022 by Aquila Kytori