Project Blender Mesh Tools add-on

[misha.physics]

I forgot to attach the file.

 

[Buck Rogers]

Maybe it's related to normals,

Yes normals

I used the mirror modifier,

before exporting apply all transforms, also check (reverse if nec.) normals especially of all mirrored parts etc.

wondering if this mesh could look smoother in game

Use mesh smoothing along with sharp edges

 

[Blake]

Select the plane then go into edit mode. Select all 'A', then press F3 and type Recalculate Normals. That command will come up. That should fix the normals isue.

The tutorial with the blender tools is pretty simple, don't know that it would cover that.

Also handy, in the upper right is the Mesh Edit Mode Overlays. Blender will show you the normals real time.

 

[Matias Saibene]

Recently I made a low poly plane from a single circle mesh using extrusion in Blender following blueprints. I thought it looks pretty accurate in Blender, namely has a good topology/geometry without any "singularities":

View attachment 39303

Before I tried to use the "Blender Mesh Tools" I converted this plane to OBJ to import it by Anim8or to export it to 3DS to convert it to MSH using the "3ds2msh" script.

Today I decided to convert it to MSH using the "Blender Mesh Tools". I followed the first three pages of the "Orbiter Tools Tutorial.pdf" and got a MSH.

It looks like the both MSH files look similar in game (but have different sizes) and have the same issues (only one side of the wings is visible, for example). Maybe it's related to normals, I don't know:

View attachment 39299

I'm going to read all the "Orbiter Tools Tutorial.pdf", maybe I will find answers to my problems there?

I attach my BLEND file here (maybe it's needed to select the object and convert it to mesh, since I used the mirror modifier, so the only half of the object has vertices). I'll be glad if someone could look at it and try it in Orbiter. I'm wondering if this mesh could look smoother in game. What ways are there to do this? Adding vertices, normal maps for textures, etc?

@Matias Saibene, maybe you could advise me something, since you're modelling your Boeing in Blender.

I'm using Blender 4 (4.0.2). And I have almost no skills in 3D modeling yet

Hi @misha.physics
unfortunately I can't open your file because I don't have Blender 4.0. On my machine it doesn't work on Linux and on Windows 10 I don't even have Intel Graphics support anymore. So I'm stuck on Blender 3.3.9.
However I'm pretty sure it's a problem with the normals as already mentioned.

By the way, from the images you posted, the 3D model looks really good! If you want to learn more about Blender I recommend Blender Guru, thanks to him I learned to model in Blender. https://www.youtube.com/playlist?list=PLjEaoINr3zgEPv5y--4MKpciLaoQYZB1Z

 

[misha.physics]

before exporting apply all transforms, also check (reverse if nec.) normals especially of all mirrored parts etc.

Now done (I forgot to apply the mirror modifier, so now both sides have vertices).

Select the plane then go into edit mode. Select all 'A', then press F3 and type Recalculate Normals. That command will come up. That should fix the normals isue.

It helped. I recalculated it outside.

The tutorial with the blender tools is pretty simple, don't know that it would cover that.

Nevertheless it could be very helpful for me regarding materials, textures and UV.

Also handy, in the upper right is the Mesh Edit Mode Overlays. Blender will show you the normals real time.

Yes, now I see normals.

Use mesh smoothing along with sharp edges

Do you mean "Shade Smooth" which doesn't change the number of vertices?

I can't open your file because I don't have Blender 4.0.

Maybe I could export my model to OBJ, for example, and you could try import it to your Blender?

I apply the "Shade Smooth" command and the "Edge Split" modifier. Notice the screenshot names:



But it doesn't look very accurate. Is it possible to automatically add more vertices, edges and faces to my model? Can it help to look better?

 

[misha.physics]

Well, at least it can fly (like DG):

 

[Blake]

A couple of things.

You don't need to apply modifiers before exporting. The mirror modifier especially is very useful and you can keep it in place. This is different from applying transforms, rotations etc. which you should do if you have been moving, resizing objects etc.

Shade smooth does not add geometry to your object, all it does is modify the normal value for vertices between planes (polygons) so that the shading transition of those planes is smooth. I generally set shade smooth to ON, and then go back and add 'split edges' where I want a sharp break between planes.

Sub surface modifier WILL add geometry, so be careful using that.

Low poly modelling is a bit of an art, and involves trade offs between accuracy and what looks good. Google 'Blender low poly modeling', there are some good resources available on YouTube.

I think that is a nice looking plane.

 

[misha.physics]

Thanks.

Low poly modelling is a bit of an art, and involves trade offs between accuracy and what looks good.

What do you mean by "accuracy"? I just thought that "accuracy" and "looks good" are the same. What is the difference?

I was going to ask, if there's "low poly modelling", than there must be something like "high poly modelling", or not? How do people make high poly models for games at all? Scan real 3D objects?

 

[Blake]

Accuracy is modelling every little seam and rivet on a wing. Too many polygons bogs down a game engine, which is why 'low poly' modelling is a thing. So its a trade off. Look at the top of your canopy. Even on the smoothed version you see the straight lines between the vertices. You can add more vertices to smooth that out, but you would not want the same 'density' of vertices in the middle of your wing where it is basically flat. Those don't buy you anything.

You could apply a sub surface modifier to the whole thing and smooth those lines out, but it would add vertices where they don't make any difference, vertices that just clog up your GPU. Putting those vertices where they need to be and not where they are not needed is kind of the art of low-poly modelling.

You can also, for example, separate the canopy into its own object and just do a sub surface on that to make it nice and smooth, but leave the body with a lower polygon count where that smoothness is not as important.

 

[Buck Rogers]

Do you mean "Shade Smooth" which doesn't change the number of vertices?

Yes, as @Blake says. There are some useful selection options for edges to help marking sharp edges.

I was going to ask, if there's "low poly modelling", than there must be something like "high poly modelling", or not? How do people make high poly models for games at all? Scan real 3D objects?

You might want to look at the subject of retopology- making high poly to low poly, which is the current gaming procedure.

Just to add to what @Blake said. When low poly modeling think about which details need to be in the mesh. Small details that aren't really seen until closeup can be done with textures and bump/normal maps. Where to draw the line is dependant on model, application and where experience/art comes in.

The model is looking pretty good, maybe one or two problem areas (nothing unusual- sharp edges, sep. mesh). it need textures! (btw extrude is the way to go!)
I like it, looks a little italian? or maybe a Yak?

 

[misha.physics]

This is different from applying transforms, rotations etc. which you should do if you have been moving, resizing objects etc.

This is something I can't understand. It looks for me that these transformas apply automatically. I moved, rotated and scaled an object and built a MSH file without doing anything to "apply" these transforms, namely I didn't press Ctrl+A to apply anything, but I see these transforms in game. But I noticed that after applying transforms I get new "initial" state to which I cat return pressing Alt+G (for example).

Shade smooth does not add geometry to your object, all it does is modify the normal value for vertices between planes (polygons) so that the shading transition of those planes is smooth.

It's interesting that after this I have less data in a MSH file. It's because we have less normals if I understand correctly.

Low poly modelling is a bit of an art, and involves trade offs between accuracy and what looks good.

So, "accuracy" means many details (polygons), whereas "looks good" means less polygons for optimization to better performance, but still make the model look nice. Correct?

(btw extrude is the way to go!)

You mean I shuld edit (extrude) some faces of the model in Edit Mode to make it look better after smoothing? It really should help.

I don't understand what's the issue with my tail. It seems to have simple geometry (1st image), but some vertical gap appears after much smoothing and Subdivision Surface modifier (2nd image):

I like it, looks a little italian? or maybe a Yak?

The blueprint I followed (top model in left view):

 

[Blake]

This is something I can't understand. It looks for me that these transformas apply automatically. I moved, rotated and scaled an object and built a MSH file without doing anything to "apply" these transforms, namely I didn't press Ctrl+A to apply anything, but I see these transforms in game. But I noticed that after applying transforms I get new "initial" state to which I cat return pressing Alt+G (for example).

It is a bit confusing. The transforms are not applied when the mesh is created, so the transform itself is still there. That can effect some things in Blender like UV unwrapping and mapping. There are times when you do want a transform to stay, for example you have a rotated part with 'child' parts you want to treat relative to the rotated parent. (not talking animations here). In the end they are given unified coordinates so it looks like the transform was applied. So in general, unless you have a specific need to retain a transform (which is probably rare) you are better off applying them as you go.

It's interesting that after this I have less data in a MSH file. It's because we have less normals if I understand correctly.

Yes, that is correct. I need to explain a bit better. Orbiter only allows a single normal per vertex. Where there is a hard break in a model, the vertex at that break needs to be duplicated so that the polygon its associated with gets the correct shading. So, when you 'mark sharp' in Blender (to create a hard corner) that does add additional vertices to the MSH file.

So I generally auto smooth an object and then go back and 'mark sharp' the edges where I do need a clean break in the shading. I'm judicious with this since it does increase the vertex count, which will impact the GPU.

So, "accuracy" means many details (polygons), whereas "looks good" means less polygons for optimization to better performance, but still make the model look nice. Correct?

Better worded as 'accuracy' vs 'efficiency'. You have to decide how much accuracy you can do without while still maintaining a model that looks good for its intended purpose, and does not needlessly bog down the GPU.

Of course as the technology improves the need for low-poly modeling and optimization becomes less important. But I still think its a good thing to be aware of.

 

[Jordan]

I don't understand what's the issue with my tail. It seems to have simple geometry (1st image), but some vertical gap appears after much smoothing and Subdivision Surface modifier (2nd image):

Subdivision Surface modifier creates soft geometry, which is why your tail is rounded. You can add supporting edges to prevent this.
Like this.

 

[Buck Rogers]

You mean I shuld edit (extrude) some faces of the model in Edit Mode to make it look better after smoothing?

Actually I meant modelling in general, it's very easy in Blender, I did the ThunderFighter pretty much extruded from a box. You can use Loop Cut to add and slide edges/vertices where you need them.

I don't understand what's the issue with my tail. It seems to have simple geometry (1st image), but some vertical gap appears after much smoothing and Subdivision Surface modifier (2nd image):

I'm a little wary of modifiers, sometimes they cause more hassle than they're worth, for low poly I'd rather use Loop Cut etc. to have more control (and I'm still learning Blender).

The blueprint I followed (top model in left view):

OK I was way off! It does have something P51 (it needs textures)

 

[misha.physics]

Thanks to all. I really need to watch more lessons on Blender. And I'll create a thread regarding mesh making with Blender.

 

[misha.physics]

I'm following the tutorial included into the tool, and noticing an interesting thing. Both the Cube and Plane have "Sort Order=50" by default:



But nevertheless it's displaying correctly in Orbiter (and the group order in a MSH file is correct, namely the Plane comes after the Cube):

 

[Buck Rogers]

If there's no sort order then they get sorted alphabetically, so "window" is a good discription

 

[misha.physics]

Hi, I made a cylinder frame in Blender and built a MSH, but it looks strange in Orbiter (it looks like some faces were added during building). Then I exported the mesh from Blender to OBJ, opened it with Anim8or, exported to 3DS, and then to MSH using 3ds2msh tool, and it looks correctly. Maybe I do something wrong, or I have to prepare my mesh before built a MSH. I attach my BLEND file.

 

[Blake]

You have a lot of duplicate geometry. Use the 'merge by distance' command. In edit mode press 'M' and select 'By Distance'. Or F3 search 'merge by distance'.

I suspect the OBJ exporter is removing that for you. I've debated adding that to the mesh builder as well, I may look at that again since it seems to be a pretty common issue.

 

[misha.physics]

Thanks! It helped.