Blender UV Unwrapping, pinning, pack islands....

[Anna Nova]

On 3/4/2018 at 7:10 PM, Aquila Kytori said:

It can be sometimes usefull to think about the UV unwrapping at the same time as you are thinking about how to create the actual model.

Using the Mirror, or Array modifier and copy pasting parts can save time if you know in advance that you will be stacking some of the UV islands :

 

 

 

Organized UV's makes it easier to later edit textures in Gimp if necessary :

 

 

 

 

 

 

Brilliant expo Aquila - as always, thank you!

I have used this technique (array, mirror, etc) in the past, but always applied before UV-mapping.   The revelation here is that by Uv-mapping before applying, you get automatically stacked UV-maps.

And how about the stripped versions for Medium and lower LODs?  Does this mean that when I strip out the unneeded detail, stretch a few planes to cover gaps, and all that low-LOD stuff,  the baked texture is still going to apply correctly?

In one of your pictures I notice that some of the quads seem to be triangulated.  Why is this?

Edited March 6, 2018 by anna2358
typo

[OptimoMaximo]

1 hour ago, anna2358 said:

In one of your pictures I notice that some of the quads seem to be triangulated.  Why is this?

Those triangles in the windows wood area are geometry splits to create the wood sticks without the addition of full edgeloops. Triangles are not an enemy

[Aquila Kytori]

 

I think you could get away with using imposters on all lower LODs.

The Medium LOD would be using the imposter texture for all except the window glass. This needs to be kept transparent like the window glass in the High LOD model.

Create the imposter image.

For this example I just made a screenshot of the textured high LOD model and resized to to a power of 2,  512 x 256 (for SL uploading ) and then greyed out the glass area so that it looked a little better when switched to Low  and Lowest Lods inworld. The correct brightness and contrast for the Imposter texture and colour for this glass can be found with more testing when the wall is rezzed.

Imposter texture:

 

An extra material (and triangle) to hold the Imposter texture is added to the high LOD model:

 

The Medium LOD mesh with new imposter material and original Glass material. The other 4 materials are hidden on triangles at the back :

 

Med LOD mesh Mapped to Imposter image :

 

The Model that will be used in both Low and Lowest LOD slots :

 

and mapped to Imposter image:

 

And rezzed inworld :

 

 

Note that now that the wall is using baked textures the model only really need 3 materials, 1: Baked texture.

2: a material for the glass. 3 The imposter texture.

 

13 hours ago, anna2358 said:

In one of your pictures I notice that some of the quads seem to be triangulated.  Why is this?

There are tris in the model because after the initial modeling, where ever possible, I like to optimize the mesh by merging vertices that are not contributing to the actual shape of the model to ones that are. This often creates tris where before there were quads.

Edited March 5, 2018 by Aquila Kytori

[Anna Nova]

11 hours ago, Aquila Kytori said:

I think you could get away with using imposters on all lower LODs.

....

 

Once again, Aquila, you explained it so well.  I am now targeting getting a lower LI than the Mesh-Generator originals.  I think with imposters at Medium, this should be achievable.

I've started in on re-making the walls using the mirror modifier...  The UV-mapping is so much easier.  I'm not as quick as you, but I'll report progress in due course.

Edit after further consideration:

I am looking at how to get all the 7 materials that I need for my actual build into this.

I need the 7 materials during the workflow up until I get to bake that texture - I thought this sort of defeated things if I have 2 imposters - now I need 9 materials.   But no, both imposters get the same texture - and 8 is OK!

But then there is also your final implication, that after that bake, I could delete 5 of the 7 materials anyway (saving a copy of the .blend file first!), assigning the remaining one to all the 'materials', because the same texture is applied to them all in SL.  This gives a lot of scope to add to the materials used to bake - as there is no practical limit to the number of them in blender, only the limit of 8 in the exported collada.  More revelation.

Sorry if everyone else finds all this blindingly obvious.

Anna.

Edited March 6, 2018 by anna2358

[Anna Nova]

Hi again.

I'm going to do a final report back, and use Aquila's style of photographic reportage.  Everything you all helped me with has worked out really well, and the first panel is now to a standard that I feel I can upload to SL and replace the Mesh-Generator version (which was 3.8LI with all the LOD's set to zero).  This is the new panel in the uploader, notice that because I am using two imposters, one for Medium and one for Low/Lowest the vertex count drops fast.  This one uses a single plane as physics...

But even using an analyzed box I get the same (but a bit more physics cost):

After upload and setting to prim, the SL dope sheet on this is good:

This is a close-up, no doubt I can work on the texture nodes and improve this, also the lighting still needs some work in Blender:

Pulling back, here is the whole panel:

I set my viewer to 1 LOD and 600M distance, so Medium comes in fast, but I can't tell the difference, I promise they are different screenshots:

Then we get to Low, still good:

and way way way away, you can still see a little detail ( like the windows!):

This is the screenshot in GIMP that I carefully posed in Beta with a large grey panel behind, to use for the Imposter texture, to the side you can see some of the transforms I did to crop it, fix the very slight perspective error, and scale it to 512 width.  Then I deleted the grey in the windows to trans:

I hope that helps someone.  I am not a professional, none of this will be offered for sale.  But the satisfaction is immense.

Edited March 9, 2018 by anna2358
typos

[Chic Aeon]

2 hours ago, anna2358 said:

I hope that helps someone.  I am not a professional, none of this will be offered for sale.  But the satisfaction is immense.

I have been wondering how this was going. Looks like you learned a TON with this project. Woot. And YES, we should remember when looking at the new Firestorm LOD tools that the numbers CAN SEEM to suggest one thing but really represent a "smart and efficient" method rather than cheating. A good reminder!

I almost always unwrap as I go -- mostly because I typically work in Materials View and like to see how things are coming together. Another timesaver  to go along with Aquila's lovely charts is keeping a copy of a piece of a mesh (or meshes) on another layer for later use. So for example you mark and unwrap a 2x6 board that is 12 feet long with a certain texture. If you need to use that board again you can use a duplicate of the duplicate (so you always have a copy of the board) and just resize and unwrap again (after rotation and scale applying of course). No need to mark seams or declare the material again. 

Also while grouping pieces by material is certainly a good way to do things and especially important if you are texturing AFTERWARDS, sometime you can get a better use of the texture plane with a more puzzle pieces approach which works just fine if you are making and baking your textures using Cycles.  The scattered materials approach wouldn't have been helpful in your house case here, but with more organic and odd shaped islands it can come in handy (like putting a piece of one material inside an empty area of another material).   So just mentioning that for the future. 

Bet you feel as good as when I completed my tool belt in Opensim LOL.   Cheers. 

 

 

[MIstahMoose]

Appreciate that you didnt use a 1k imposter

Great stuff, Great thread to read too.

Edited March 8, 2018 by MIstahMoose

[Aquila Kytori]

3 hours ago, anna2358 said:

also the lighting still needs some work in Blender:

I'm quite new to Cycles (my old PC often crashed when I tried using it) so this may not be good idea , maybe Chic could comment on this approach to lighting :

I started adding lamps to the scene then I thought instead of positioning lamps why not try HDRI image as lighting?

I was happy enough with the result it gave. I wanted rich colours and found giving it lots of AO helped for that.

The only problem I had with the bakes was:

1: the AO was very rough (no anti aliasing) so later I gave the texture a little Gaussian blur in Gimp.

2: The faces that were receiving maximum lighting from above were getting fireflies (little white spots in the bake) but with a little Googling I found that this could be reduced or in my bake completely removed by enabling Multiple Importance in the World tab > Settings. (The Denoising option works well in render but not at all when baking).

 

[Anna Nova]

2 hours ago, Chic Aeon said:

I have been wondering how this was going. Looks like you learned a TON with this project. Woot. And YES, we should remember when looking at the new Firestorm LOD tools that the numbers CAN SEEM to suggest one thing but really represent a "smart and efficient" method rather than cheating. A good reminder!

I almost always unwrap as I go -- mostly because I typically work in Materials View and like to see how things are coming together. Another timesaver  to go along with Aquila's lovely charts is keeping a copy of a piece of a mesh (or meshes) on another layer for later use. So for example you mark and unwrap a 2x6 board that is 12 feet long with a certain texture. If you need to use that board again you can use a duplicate of the duplicate (so you always have a copy of the board) and just resize and unwrap again (after rotation and scale applying of course). No need to mark seams or declare the material again. 

Also while grouping pieces by material is certainly a good way to do things and especially important if you are texturing AFTERWARDS, sometime you can get a better use of the texture plane with a more puzzle pieces approach which works just fine if you are making and baking your textures using Cycles.  The scattered materials approach wouldn't have been helpful in your house case here, but with more organic and odd shaped islands it can come in handy (like putting a piece of one material inside an empty area of another material).   So just mentioning that for the future. 

Bet you feel as good as when I completed my tool belt in Opensim LOL.   Cheers.

I don't pretend that I got max-pack on this first one, but I'm quite pleased with the lack of black.....

I have a tendency to take .blend snapshots as I go through the workflow, that way I can usually use the Append to grab things that I used in one mesh in the next.  The struts and understruts on these panels migrate like that....

And, ya, I do feel pleased.  Especially in this awesome company.

[Chic Aeon]

2 hours ago, anna2358 said:

I have a tendency to take .blend snapshots as I go through the workflow, that way I can usually use the Append to grab things that I used in one mesh in the next.  The struts and understruts on these panels migrate like that....

Yes append is great and for materials also -- and even lighting set ups. Happily I have a pretty sharp memory so unless something is really old I know where it is in my folder system (by date). AND I am getting better (or trying to be better) NAMING the meshes as in "table", "chair", "lamp" which can all be in one event file sometimes.  MUCH better than "cylinder" or "cube" as a designation.  LOL

 And really I think your map look very good. Remember one of the pros mentioned having some space between things. Sometimes blender does things well when packed tight and sometimes notsomuch -- so flexibility is a good thing!   

[Anna Nova]

10 hours ago, Chic Aeon said:

...

 And really I think your map look very good. Remember one of the pros mentioned having some space between things. Sometimes blender does things well when packed tight and sometimes notsomuch -- so flexibility is a good thing!   

There is that Margin setting in the Bake panel that controls how much 'spill' there is around an island.  It gets kinda critical when the UV is very dense.  I tend to start at 1px (after watching your videos), but the blender default is 16px.  It's probably a fruitful area of experimentation.

[Chic Aeon]

6 hours ago, anna2358 said:

There is that Margin setting in the Bake panel that controls how much 'spill' there is around an island.  It gets kinda critical when the UV is very dense.  I tend to start at 1px (after watching your videos), but the blender default is 16px.  It's probably a fruitful area of experimentation.

Yes, I typically use "1". I think that the baking (even in Cycles Render) is one of the things that could use some improvement in Blender. The margin padding only affects SOME of the edges (not the inside of a circle for example) and baking anything at an angle gives jagged edges that need to be fixed in post processing.  Awhile ago some pros that apparently didn't actually use Blender in their daily life (not surprising) tried to help me with that issue. I did do a bunch of tests but didn't come up with any better results. So some things (not so much what you are working on now) are issues. 

BUT Blender is a huge program and only a small portion of folks use baking as we do (I suspect such anyway). Easy to see why better baking isn't on the top of the todo list :D.  You CAN of course map things ONLY as rectangles (well sometimes anyway) and use the UVmap node to adjust so that you don't have a seam, but that can get very complex depending on the project so questionable if it is worth the effort. Great for vases and such that are single objects, not so good for things that need LOTS of "seamless seams".  

I have NO idea why 16 is the default. That is completely ridiculous unless you are baking a 4096 x 4096 or something. But again, we are looking at the choices from OUR perspective.  

[Aquila Kytori]

13 hours ago, anna2358 said:

There is that Margin setting in the Bake panel that controls how much 'spill' there is around an island.  It gets kinda critical when the UV is very dense.  I tend to start at 1px (after watching your videos), but the blender default is 16px.  It's probably a fruitful area of experimentation.

Its important to leave enough space between UV islands and the Margin in the Bake panel can be left at 16 (or even increased).

Quick example of seams appearing in a texture as you zoom out from the object because the the padding margins are to small :

The seams are even more noticeable than they appear in these screenshots.

See artons reply in this thread :

Or have a read here  : http://wiki.polycount.com/wiki/Edge_padding

 

Edited March 9, 2018 by Aquila Kytori

[Chic Aeon]

2 hours ago, Aquila Kytori said:

Its important to leave enough space between UV islands and the Margin in the Bake panel can be left at 16 (or even increased).

Quick example of seams appearing in a texture as you zoom out from the object because the the padding margins are to small :

The seams are even more noticeable than they appear in these screenshots.

See artons reply in this thread :

Or have a read here  : http://wiki.polycount.com/wiki/Edge_padding

 

Are your examples done in Blender Render? Because I remember that seam from "back in the day" but I have had no issues at all with 1 pixel margins on 1024s or 512 bakes in Cycles.  Not sure what else might make a difference.  

 

[OptimoMaximo]

7 minutes ago, Chic Aeon said:

Are your examples done in Blender Render?

Chic, that is independent by the software that baked the texture. It is something done in the graphics engine, mip mapping, the texture version of LoDs. At each distance increment, the texture gets smaller and smaller, and by doing this it becomes more and more blurry and finally pixellated, so much that the background color begins to spill into the UV shell and becomes therefore visible.

Edit: example, if the background color in the baked texture was red, those lines would appear to be red.

Edited March 10, 2018 by OptimoMaximo

[OptimoMaximo]

Can't add this part to the edit :\

You could also bake with no padding over an alpha transparent image and then run an edge padding filter either in photoshop or the gimp

Photoshop tool is FlamingPear scriptset (free), solidify filter

Gimp tool's name is UVPadding

They both do an excellent job, filling the whole texture (infinite padding) if you find Blender's padding feature not really consistent, as i read from a post above

[Chic Aeon]

46 minutes ago, OptimoMaximo said:

Chic, that is independent by the software that baked the texture. It is something done in the graphics engine, mip mapping, the texture version of LoDs. At each distance increment, the texture gets smaller and smaller, and by doing this it becomes more and more blurry and finally pixellated, so much that the background color begins to spill into the UV shell and becomes therefore visible.

Edit: example, if the background color in the baked texture was red, those lines would appear to be red.

OK. Just wondering why I don't see this effect any longer when baking with 1 pixel margin.  Any ideas?

I remember this problem WELL when I first started working with Blender. Haven't seen it in a VERY long time. Actually I don't remember seeing it on work of others either. Maybe a viewer setting?  Puzzled.  I bake at 400 and 500 normally. 

[OptimoMaximo]

Perhaps a debug setting was set to a new default?

[Chic Aeon]

3 hours ago, OptimoMaximo said:

Perhaps a debug setting was set to a new default?

If so that was an excellent move - LOL. 

 

 

[OptimoMaximo]

9 hours ago, Chic Aeon said:

If so that was an excellent move - LOL. 

IMO, Not really, Chic. Changing how mip mapping manages the distances at which each mip reduction is being performed is exactly the same as increasing the RenderVolumeFactor for the mesh that lacks proper LoDs, just applied to textures. Texture load then should be affected. Ah well, IF this was the case, of course.

[OptimoMaximo]

Oh and another thing: this may be happening client side, others might be seeing the regular behavior that Aquila has shown. Definitely i do see the mipping caused seams. Less and less frequently though, to say the truth.

[Chic Aeon]

2 hours ago, OptimoMaximo said:

Oh and another thing: this may be happening client side, others might be seeing the regular behavior that Aquila has shown. Definitely i do see the mipping caused seams. Less and less frequently though, to say the truth.

Note that I "CAN" see the seams as the item loads and before the textures are fully rezzed. Not counting that as "this issue".  Just for the record. There was one point LONG, LONG ago when I can remember making a biggish vase. I even remapped the mesh WAY inside the texture islands -- using the previously baked texture and rearranging the new mapping well inside the existing texture areas. The vase still had this issue. That was so long ago I could have been doing tons of things wrong so have no clue there. 

Still very interested to see what changes will come about in the new land impact rules. Of course LL announces things that are going to happen SO FAR ahead of when they do happen it could be 2020 before we see that LOL.  

[OptimoMaximo]

12 minutes ago, Chic Aeon said:

Note that I "CAN" see the seams as the item loads and before the textures are fully rezzed. Not counting that as "this issue".  Just for the record.

I wasn't thinking of that loading time effect either  

However, i haven't encountered (yet) a behavior like your vase, so far.

 

[Chic Aeon]

2 hours ago, OptimoMaximo said:

I wasn't thinking of that loading time effect either  

However, i haven't encountered (yet) a behavior like your vase, so far.

 

That was probably five years ago. Hopefully "that" has been fixed :D. Nasty.

[Love Zhaoying]

2 hours ago, Chic Aeon said:

Still very interested to see what changes will come about in the new land impact rules

I’m so out of touch, the current LI rules still feel “new to me”!