There's enough dark magic in UV unwrapping for its very own page, so we've started one 😀 Intended mostly as a 'beginners crash course' but with room for experts at the end: http://pioneerwiki.com/wiki/UV_coordinates_in_Blender

Finding good textures seems to be a major bugbear for modellers. If anyone knows of any that are license compatible with Pioneer, put them here: http://pioneerwiki.com/wiki/Textures

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(Thanks John - looks like some really good tips. I'll read that properly later...)

(P.p.s. maybe this could use a sticky?)

Those are some good guides, I might actually give Blender a try again if I can follow those.

Some good tips there, could have done with some of those a couple of months ago. I am still really struggling with UV unwraping, I understand the concept but it just never seems to work out cleanly (without a lot of manual work) in practice.

Mikehgentry - 'Seams' are where YOU want meshes 'cut' rather than letting blender decide for you. 

Mikehgentry - 'Seams' are where YOU want meshes 'cut' rather than letting blender decide for you. 

I want the other way round where I can join two meshes together to unwrap as one.

Example.

I have 2 meshes. Hull_Top and Hull_Bottom.

I can successfully unwrap Hull_Top to the UV editor view but when I goto then unwrap Hull_Bottom, the UV for Hull_Top dissapears and I can only see Hull_Bottom.

I can now see the UV's for Hull_Top and Hull_Bottom in the UV editor window but not at the same time.

So how do you unwrap both meshes at once or unwrap the entire model so that you can see all the polygons in the UV window so you can pack them efficiently and export them in the same .png?

Some good tips there, could have done with some of those a couple of months ago. I am still really struggling with UV unwraping, I understand the concept but it just never seems to work out cleanly (without a lot of manual work) in practice.

 

Mikehgentry - 'Seams' are where YOU want meshes 'cut' rather than letting blender decide for you. 

I've played around with them, just couldn't make it work properly for some reason. I'm leaving that part for someone with some experience of it actually doing what it's meant to do...

I want the other way round where I can join two meshes together to unwrap as one.

 

Example.

I have 2 meshes. Hull_Top and Hull_Bottom.

I can successfully unwrap Hull_Top to the UV editor view but when I goto then unwrap Hull_Bottom, the UV for Hull_Top dissapears and I can only see Hull_Bottom.

I can now see the UV's for Hull_Top and Hull_Bottom in the UV editor window but not at the same time.

 

So how do you unwrap both meshes at once or unwrap the entire model so that you can see all the polygons in the UV window so you can pack them efficiently and export them in the same .png?

Only suggestions I can think of are to join the meshes together for the purposes of unwrapping.

Or to unwrap one, using only half of the available UV space. Draw a texture on it, then use it instead of a 'New' file for the second mesh.

My suggestions are:

• Merge the two meshes, once you've modelled them both there's no reason for them to be separate anymore.
• Alternative 1 - guesswork, make sure that mesh 1 is all in the top half of the UV/png space and mesh 2 is all in the bottom half.
• Alternative 2 - Unwrap mesh 1, export png, unwrap mesh 2, export png, merge the two pngs... if they overlap repeat process but move them around a bit, repeat until UVs don't overlap.

Personally unless you've got a good reason for keeping them separate you could just merge it all into a single mesh which might be the easiest.

Andy

I've played around with them, just couldn't make it work properly for some reason. I'm leaving that part for someone with some experience of it actually doing what it's meant to do...

 

 

Only suggestions I can think of are to join the meshes together for the purposes of unwrapping.

 

Or to unwrap one, using only half of the available UV space. Draw a texture on it, then use it instead of a 'New' file for the second mesh.

They are both superlative suggestions with only two minor drawbacks.

1) I don't know how to join meshes together yet (EDIT - I do know now....ctrl+j)

2) I never thought about doing the second one.

My suggestions are:

• Merge the two meshes, once you've modelled them both there's no reason for them to be separate anymore.
• Alternative 1 - guesswork, make sure that mesh 1 is all in the top half of the UV/png space and mesh 2 is all in the bottom half.
• Alternative 2 - Unwrap mesh 1, export png, unwrap mesh 2, export png, merge the two pngs... if they overlap repeat process but move them around a bit, repeat until UVs don't overlap.

Personally unless you've got a good reason for keeping them separate you could just merge it all into a single mesh which might be the easiest.

 

Andy

I'll figure out how to merge the meshes together tonight (depends on boy sleeping however and not being a mardy git like he was last night)

EDIT - I figured it out now, ctrk+J. really should not be fiddling with blender at work but hey ho 🙂

Thanks again you fine guys.

Don't get fired! 🙂

Says me posting from my work! 😀

My suggestions are:

• Merge the two meshes, once you've modelled them both there's no reason for them to be separate anymore.
• Alternative 1 - guesswork, make sure that mesh 1 is all in the top half of the UV/png space and mesh 2 is all in the bottom half.
• Alternative 2 - Unwrap mesh 1, export png, unwrap mesh 2, export png, merge the two pngs... if they overlap repeat process but move them around a bit, repeat until UVs don't overlap.

Personally unless you've got a good reason for keeping them separate you could just merge it all into a single mesh which might be the easiest.

 

Andy

You do want separate meshes if they've got different shininess or transparency though right?

You do want separate meshes if they've got different shininess or transparency though right?

some of the 'shininess' can be controlled by a specular map and you want to have any parts of the model that use transparency to have there own mesh, material and texture

I understand mesh and material. Why do they need a different texture?

Two different things might get confused there.

Meshes with transparency want to have a separate texture, so things like a cockpit area would be a separate mesh and go onto a separate texture with an alpha channel.

Then the rest of the ship mesh gets mapped onto another texture without an alpha channel.

This is for rendering performance, rendering with alpha testing is a bit more expensive than without.

It's not a huge issue with Pioneer at the moment, but we'll get there pretty soon if we don't start of doing the right thing from the start 🙂

Ah, OK. I was thinking transparency was defined in the model file, but it isn't actually is it.

I think that makes sense...

- edit

Dag nammit, there's an opacity in the model file. So what does that do???

opacity 0-100, controls transparency of the material. A node with a material opacity less than 100 is treated as transparent, otherwise opaque.

Well, that seems to work for the whole mesh. I guess I'm just not sure which situations it's preferable to use one, and which the other. I'm guessing it's the distinction between wanting an entire mesh to be translucent vs. wanting parts of some surfaces to be translucent...

ok so this is what i have figured out if you have a texture that has a fully transparent part you need to use an alpha channel in the texture to mask the transparent part then use the opacity setting on the material set it to 99 and only the part masked by the alpha channel will be see through. if you keep lowering the opacity then the rest of the texture will start to become see through

i hope that makes sense iv had a long day

That seems to make sense. I think what you're saying is

opacity

0 - 98       mesh is translucent

99            mesh is solid apart from surfaces set by alpha channel

100          mesh is solid

I don't have any textures with alpha. I'll whip one up then do some experimenting...

Thanks all!

Hmm, i'm not sure now, unless Luomu chips in I'll have to check.

I've been playing around with it - seems to be more or less correct. Settings below 99 do take account of the alpha channel, but their overall opacity is set in the .model file.

To take advantage of the rendering performance improvement from not having an alpha channel, do you have to remove the alpha channel from the .png, or does the engine simply ignore it if the opacity is 100? I guess removing the alpha channel does no harm, and maybe shrinks the file fractionally anyway...

First of all, I think there is a bug and the game does not detect a transparent texture correctly. Will fix this tomorrow or thursday when I get pioneer-time. Forcing it with the opacity value can be used for now.

The opacity setting is for if you simply want to have glass or other transparent material without using any textures. Or you can use it to multiply the texture alpha channel if you wish.

Yes, you should remove alpha channel from a texture unless you intend to use it.

So besides the alpha texture fix and two-sided material flag I think I will also add an alpha test material flag. Otherwise you'll get alpha blending which gives softer edges but it also has drawbacks. Here's one explanation: http://docs.unity3d.com/Documentation/Components/SL-AlphaTest.html

Right, I've implemented the following (you'll have to wait for the next nightly or release):

- geometry with alpha texture is not automatically treated as transparent. I decided this was too error prone (photoshop saves pngs with alpha unless you flatten the image). Still, I recommend not to include alpha channel needlessly.

- alpha_test material flag added, use this for fences, grating, trusses etc.

- unlit material flag added. Good for station interiors, where you don't want sunlight.

- two_sided material flag added. This does what it says, however it cannot automatically flip the normals on the opposite side, which means lighting may not work as you expect. I recommend you just duplicate and flip geometry to get two-sided effects.

Thanks Luomo.

I started a page on the subject. It's perhaps not complicated enough to warrant one normally, but it doesn't really fit in any one subject (textures, meshes, model system...) so saves repeating ourselves.

http://pioneerwiki.com/wiki/Transparency

WIP, I thought a tutorial that went from start to finish through the process of making a very simple ship and getting it into Pioneer was in order. Unfortunately I'm on someone else's Mac, and these things are a mystery to me, so hit a bit of a wall, but I'll finish it up next week when I'm really back home... Additions and corrections welcome in the mean time!

http://pioneerwiki.com/wiki/Making_your_first_ship

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Also, nearly forgot - here's the very basics of turning pointy clicky Blender events into a script. The video tutorials linked at the end go on forever and ever, but they cover much more...

http://pioneerwiki.com/wiki/Scripting_Blender

That's pretty cool. I'm not a modeller, but were I to give it a go, I would not be intimidated by that page. This is a good thing.

Thanks. I think it's heading in the right direction - keeping it very simple, so hopefully none of the usual "Build your space ship, then continue from section 2"... 🙂

--ETA

That's a dig at Blender's docs, by the way, in case that isn't clear. Pioneer's docs aren't brilliant, but they're pretty good considering how few of you there are...

[attachment=1702:Bildschirmfoto 2013-02-24 um 22.46.58.png]

[attachment=1701:Bildschirmfoto 2013-02-24 um 22.46.52.png]

if you have two separate objects you can join them, but i recommend then to set for each part a new material, if you like them splitted at all you can split then by material use.

if you like to keep them separate , i would unwrap and export the uv to a bitmap, you find that in the uv/image editor window when you switch to edit mode.

[attachment=1703:Bildschirmfoto 2013-02-24 um 22.59.41.png]

then you can load the uv of one obj to position the mapping of the other, if that was what you liked to do.

e.g to unwrap a lower LOD mesh.

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but i see no reason for collada not to use the mesh materials (if you use at all more as one material) and to export finally all to one model.

thrusters and other nodes of course only once, when you export the model you can select with shift the needed two or more layers,

select all and of course export only selected.

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some of my projects for SGM i made so far (and a few other) you find here,

http://sdrv.ms/YPnw02

might be helpful for someone to snoop into them.

i have to say in advance that i first stripped them of old material, so it's prob. not all material i used,

i.e. exported meshes i used as base for the project used original textures.

mainly only the latest blender project(s) and the gimp project for the texture.

don't be surprised most animations i made exclusively in blender2.49, but you can open the file with 2.65, no problem

only exporting to collada or any else won't work from blender2.65 or not as expected.

it's just because i can't get the conrods working except for .x and only with blender2.49.

but probably i'm to blind to see a solution, or whatever, maybe it really doesn't works.

the problem is, i would have to use "visual keying" for the constrained objects,

but as soon as i set the first "visual key", the animation gets mixed up

and the movement ends somewhere complete different as it was set/limited through the constrain.

but i will see next week, i have a idea why this prob. happens.

on the other hand, i don't care to much, you can imagine.