ajz3d

Try disabling Edit->Customize UI.

In this particular case, islands that are outside of the (0,1) UV space are treated as being inside it. So they will overlap with any other UVs that are at the same location, but inside the (0,1) square. You need to keep this in mind.
 
 

  Yes. But you don't have to move all overlapping parts, just what is necessary for you to comfortably use projection painting. I'd go with the trial and error approach and move only those islands that I don't want to be affected when I'm painting something else. Some of the stacked UVs are pretty useful as they save texture space (like islands of the pistol grip). This comes at a cost of course, because everything that you paint on one stacked island, will show up on the others too.
I never use projection painting, but it looks like it projects the painted layer on every front face that lies on projection's depth axis. This is why some parts of texture appeared on the barrel. You painted over the outer part of the pistol grip. Under this part there's the main pistol grip which shares UV space with some barrel parts (some being outside of (0,1) space). Your layer was projected into the outside part of the grip, then the inside part, and as a result - into barrel because, to repeat myself, their islands share the same UV space. That's how I see it.

Hi.
Well, yes and no.
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"Yes", because technically you can use Copy Channels to copy each of these PBR channels to colour of other paint layers (E.g. source layer's glossiness to destination layer's luminance channel, etc.) Then export several versions of your model, each containing different data written to vertex colour. PLY format supports vertex colour, so I'd use that. You'll end up with several .ply files, each containing different channels in their vertex colours.

This is where things get a little bit tricky and the trickiness depends on the software you use.

If you're familiar with Houdini, you can import all those models and copy Cd point attributes of each one of them to appropriate point attributes of your render geometry (you'll need to create those attributes). Then you'll need to modify your shader to use these custom attributes instead of texture files for each shader's parameter that correspond to appropriate PBR channel that you have written inside vertex colour of your models.

If you don't use Houdini, then you can resort to MeshLab. Import one of your .ply files. You need to apply some kind of texture parametrization. You have a choice to use either Trivial-Per-Angle or Voronoi Atlas (I suggest the latter), but first you have to launch a Per Vertex Texture Function (default parms will do). Now start either one of parametrization functions. I'll only explain Voronoi Atlas. With it you'll need to define number of UV islands. I guess the more of them, the better. It will create a new mesh layer called VoroAtlas, or something like that. Select it and export it to, say, .obj, but remember to include wedge TexCords. Vertex normals are optional. This will be the file you will be rendering. Now, the new mesh has uv coordinates, but does not have any texture yet. Choose Filters->Texture->Transfer vertex attributes to texture (between 2 meshes) and choose your original mesh as source and the VoroAtlas as target. As a vertex attribute to copy, select vertex color, choose the desired texture resolution and filename. Leave the rest as defaults. As a result, a new texture map will be created on the disk (for some weird reason it won't appear on your model even if you have selected Assign Texture in the options window). To copy other maps, keep VoroAtlas mesh on the layers list, sequentially import other .ply files, copy their vertex colour to the VoroMap and remember to change texture file names according to what vertex colours of those .plys store.
 
The thing is that Voronoi Atlas function likes to freeze MeshLab in an endless (or maybe not?) loop.
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And "No", because Copy Channels appears to be broken...
 
P. S. Sorry for bad formatting, but Mr. Morpheus will be visiting me any moment now.

Or you can just paint with Freeze tool over a stencil (Windows➞Popups➞Stencils).

Remove intersection with... will remove the intersecting parts of two volumes and leave the rest on their own VoxTree layers.

Is this what you're after?

That's camera roll.
Go to Customize Navigation and Add Event called Roll in Screen Space. Set a hotkey and you're set.

Hello Tim.

24-bit format is okay, like JPEG, PNG or other. I suppose 8-bit grayscale will work too. To address your second question - I don't remember, but I think it was "edge detection" with default settings. You can skip this step (and Photoshop/Gimp import) completely and import PDF file directly into InkScape. I did it the other way, because loading and manipulating the file in InkScape took way too much time for my liking.

File-Save As...->Encapsulated PostScript (*.eps) It doesn't have to be EPS, but something readable in one of your 2D applications. You can also directly export (File->Export) the traced image to high-res raster image, just make sure you do this in very high resolution. I chose EPS because it's universal, takes very little storage space, and when I import it to Photoshop I can set whatever resolution I want without loosing quality.

Try what Tony suggested. Also, I recorded a more detailed video:
https://www.dropbox.com/s/7s1pjut6ldanahd/sketch_tool_2.mp4?dl=1
And a stencil that you can use to do some tests: https://www.dropbox.com/s/uzjg86aq29bxif7/club.tga?dl=1

Okay, there's a simpler way of discarding vertex colour information.
Create an empty surface layer and select it, if it's not already selected. Select Import tool and disable Import to Separate Instances. Apply. This will use vertex colour information from newly created VoxTree layer, which is... None.

The direction of main viewport light is global and is stored in options.xml. Look for LightDirX, LightDirY, LightDirZ.
Camera position and orientation is scene-based and therefore is most likely located in 3b files.

It's possible, but the process is a little bit awkward.
 
You can create tiles in retopo room by creating UV-sets and assigning selected faces/islands/objects to them. At first, those UV-sets will be just that - UV-sets, and will remain in 1,1 UV grid. Don't worry about it. Now, in the Import object for per pixel painting, make sure you have Import tiles as UV sets disabled. To export the model with UV tiles, go to paint room and select File->Export model. Make sure that Export UV sets as tiles. This will treat each UV-set as a separate tile and will place them along the U axis.
 
There are several things that you need to know:
1. You don't have any influence on the order of tile placement. They're all put along U.
2. 3D Coat won't place tiles on V greater than 1. So, if you want UDIM for example, you'll need to move those tiles into place later in some other software.
3. If some of your UV-sets are supposed to be tiles and some you want to remain in 1,1 space, then it's not possible. That's because if Export UV sets as tiles option is enabled, all UV-sets will be treated like tiles and put in a horizontal sequence. So that UV-set that you wanted to remain in 1,1 will probably end up somewhere outside of this coordinate.
 
That said, what I do after exporting a model with UV tiles is that I open it up in some other program and move those tiles where I want them to be. At the same time I rename texture files according to UV tiles positions.
It's very tedious, but it works.

Have you looked at the list of UV sets in 3D Coat? Most likely a new UV set (with your retopo group assigned to it) was created on import and is currently not selected, hence your group is deactivated.