Textures and Texturing

With my old copy of MAX 2.0 I have some problems with exporting as 3DS. As this is down to the age of my software I have placed the side-note on 3DS export. on a separate page.

Texturing
3DS into OPTech via 3DSOPZ | OBJ into OPTech | DXF into OPTech | gMAX into OPTech via a converter and 3DSOPZ

Textures

Introduction

The textures are extremely important and so can be (and normally are) the stage of the OPT making process that takes the most time.
A model which is going to be used in a 3D modelling / animation package can sometimes have quite simple "diffuse" textures as much of the detail would be in the model or would be created when the model was rendered and different effects for reflections / shine / illumination / bump-mapping etc were applied.
In XWA though the model is simpler and each face has only one texture. Since this has to contain all the information to make one surface look different from another (rather than this being a combination of material settings and other texture-maps for the different "effects") it can be quite complex.

For parts where you are going to use planar mapping a useful tip is to render some guides from the model. Setting up material IDs can be quite useful for this as it means that you will be able to select only those faces which would have the same texture being applied.

As stated before the maximum safe size for textures is 256*256, as this will work with all systems (to the best of my knowledge), but you can use 512*512 if you are willing to exclude some people in favour of having more detailed textures. It should be possible though with a reasonably complex model, or where a ships design means the model has large faces (for example the large flat surfaces on Star Destroyers) by splitting faces, to be able to select each quarter of the faces the 512*512 texture would have covered and apply a 256*256 sized texture to each.

Of course, or at least in my opinion, most of your individual textures should not be this large for two reasons.
Firstly although a 256*256 size texture is not that large (in terms of file size) if you have dozens of them then you are going to have a rather large OPT (in terms of file size) which will take longer to upload/download, which XWA will take longer to load (and could cause in-game pauses as ships are loaded as encountered, I think), and which will require XWA to be working harder to process that many large textures (which again could slow things down).
Secondly in some ways it is easier to maintain the same level of detail between different textures if the relative sizes of the textures are roughly in line with the relative sizes of the different parts they are being applied to. There are exceptions, places where you want to have more detail as they player would be examining them more closely for some reason, and you don't want to have any textures being too small (so you would either make them larger, or make the largest textures smaller and increase the other textures size by one "step") but you want the OPT to look consistent.

On the other hand if you are using methods to combine more than one texture together (see section) then you should be aiming to combine these into as few 256*256 sized textures as possible. So although your "sub"-textures won't all be as large as 256*256 you might manage to have a lot of textures of this size, depending on how many can be combined.

Unless you are making a ship which has been built by joining together debris or components from other ships (normally an "Ugly" fighter though larger ships could be built, or at least have equipment added, with the same Scrapheap Challenge philosophy) you should keep your textures similar in their colour and design. This can be a problem sometimes, especially if textures are supposed to be seamlessly joining, as when colour-depth is reduced the brightness can be slightly altered (see below).

Remember that although you will want to make your texture names nice and descriptive that if you plan to export as a 3DS file that this format may have an 8.3 limitation on the filenames used for textures within it, or it may not (my obsolescent MAX 2 does but from what I can gather later versions of MAX as well as not "exploding" the model by displacing meshes can also deal with 3DS files without needing to play around with truncated names). This can be rather irritating.

Rough step-by-step

I use a program called Satori to make my textures. This was previously available as freeware but when getting the URL for their site I noticed that freeware version 2.29 has been withdrawn, but full version 3 is available for $9.95 / £6.95 which seems very reasonable. I actually use an older version though which I got on a magazine cover CD as I prefer the look of the interface.

This is rather an uncommon choice of art package though so you would be best advised to read the other texture creation tutorials which are available and which cover the more normal choices.

The first thing I do is create a base on which all related textures can be built by producing a large image from which I can cut out bases of different sizes. This is slightly easier than going through the process for each texture individually and helps to ensure that the related textures are the same shade and colour.

I create a new canvas of the appropriate size and apply a base colour which is slightly lighter than the final shade I want the ship to appear. This is slightly lighter to allow for how the effect of the panel lines, dirt, and shading will make things appear darker. I normally make a note of what the RGB values for this colour are so I can use the same colour for related textures.

I then try to introduce a bit of variation into this base colour rather than it being totally flat. This can be done using different tools either darkening or lightening the colour (see Metals) or painting on with different effects a slightly different shade of the colour. You can make this variation quite strong as it is simple enough to create another layer, apply the original base colour to it, and then adjust the opacity of that layer to weaken the strength of the variation by changing how strongly it shows through.

Once I have a nice image which can serve as the basis for the related textures I then cut out a section of the correct size and begin work. The first thing I normally do is to create the panel lines as a guide for where dirt and shading should be. These can be created in a dark grey and then burn and glow tools (or their equivalent) can be used to introduce a small amount of variation. The panel lines should be on a separate layer so that their opacity (and therefore how strong the panel lines are) can be easily changed.
This is also useful if you have decided to use bump-mapping to enhance the textures as it makes it simpler to create the bump-map. In this case you will need very weak panel lines (a almost transparent layer) as the panel lines will be being marked by the bump-map and so do not need to be marked strongly on the "diffuse" texture as well.

After I have set up the panel lines I then add some extra panelling if the texture is meant for a ship large enough that each "panel" would be made up of more than one actual plate of metal. This can be simple enough as a good effect can be obtained by just drawing rectangles of various shades of grey (or slightly off-grey) onto another new layer and then adjusting this layers opacity so that these give the effect of slightly raised or recessed panels or simply those whose paint doesn't quite match that of those surrounding it.

Next I start to apply shading to the texture. This should not be too strongly orientated towards one direction as the OPT will be lit from different angles in different missions or skirmishes in XWA and so if you have strong shadows on the texture these will not always match those created by the lighting in game. However some fairly subtle shading around the edges of panels, around areas of the texture that will appear recessed or extruded, and the like will enhance the texture as there will always be a change in tone there.
One thing I advise is that before you start applying shading that you should copy the layer with the base texture, that way if you (as is likely) make the shading too strong by repeatedly going over different areas you can blend back in the unshaded version of the base and reduce the strength of the shading.

Dirt and damage is something which is a Star Wars trademark and which has become in part a catchphrase of OPTing with the advice that an OPT "needs more dirt." A good guide for this sort of thing is not modern fighters (or vehicles/ships) as these tend to have not been subject to hard use, unlike some Star Wars ships, and so tend to be quite immaculate. A better guide is W.W.II fighters (or vehicles/ships) as they were being used to their limits on a daily basis over periods of weeks or months and being maintained by people whose priority was to keep them operational rather than repainting every last bit of chipped paint.
Remember though that how much dirt and damage an OPT should have depends on what sort of people are going to be using it and how concerned they are about maintenance and appearances.
At one end of the scale you would have someone like Han Solo who liked having a battered scorched and dirty hull as it led people to underestimate his beloved Millennium Falcon, so if you are doing a smugglers craft you could have a lot of "muck" in the texture.
At the other end of the scale you would have the Imperial Starfleet who have the resources to replace any damaged armour (rather than leaving a potential weak-spot in their hull) and a desire to maintain standards of appearance which can be met by sending crewmen on punishment detail EVA to clean the hull (and examine any scorch marks to see how deep the damage goes, check if it is just paint or if it has penetrated layers of hull armour). In this case you would have quite clean textures but would be able to have some variation in shade between hull sections to reflect that some are replacements with clean fresh paint.

Something that can look good on an OPT is markings and decals, things like little warning triangles, notices, panels being outlined in a different so that ground crew know which panel to remove to expose what component, that sort of thing. These are mainly found on smaller craft such as fighters but anything where guidance (arrows pointing to docking ports) or a hull symbol (like a Rebel or Imperial crest) would be appropriate could have this. One thing to remember though is that Star Wars people may seem to speak English but they don't really so any text should be in Aurabesh.

Finally try fiddling with the opacity of the different layers and changing how they blend together and how strong different elements are. You may want to save as a JPG at this point to check how it will actually look since sometimes things can look better in Satori then they turn out when the "canvas" is turned into relatively small bitmap. Once you are satisfied with the look of the texture then save it as your "final" version JPG.

Next if you have decided to use bump-mapping to enhance the textures delete all layers that do not have panel lines or bulges on them. Unless the ship is very uneven you would not generally need the panelling layer. Create a new layer and make this solid mid-grey (128,128,128) before moving it "behind" the other layers. Now change the opacity of the panel line layer(s) so that they are very strong (normally a 100% opaque layer) and save this as a JPG (normally of the same name as your normal texture, but with "b" or "bump" on the end).

The texture (either your final texture from your art package or the result of some rendering in your 3D modelling package) will need to be converted into a 256 colour BMP file and if you are using cylinder mapping for this texture (at least in MAX) also rotated 90 degrees. Depending on how you are texturing your model you may also want to apply this texture to the model at this point just to see how it looks.

Techniques

Metals.
The best method I have found for creating a nice metal effect in Satori was to make myself a custom brush (which I imaginatively called "metal") which combined the Burn brush with the Charcoal. This brush would then darken whatever it was painted over, like Burn, but thanks to the Charcoal effects it creates a metallic looking grain rather than just a dark streak. Different brush sizes produce different coarseness / fineness of grain and so by going over the same thing a few times with different sized brushes a quite complex pattern (appearing to be made up of different sized imperfections) can be built up.

Flightgroup stripes and other markings.
As mentioned before Star Wars ships can be quite battered looking and so if you have a simple stripe on the hull then this will look rather out of place. Even if there is no air in space there is dust and very small amounts of gas which can produce weathering effects. Therefore Flightgroup stripes and other markings need to look a little worn and battered around the edges.
The method I use for this is to create a mask on a new layer so that the effects of any brushes used on that layer are restricted to inside that mask (just as if you put a stencil on something then the paint should only come through the holes in the stencil). Then I fiddle around with applying different brushes with slightly varying shades of my target colour (blue, red, green, yellow, or whatever), trying not to make it too solid a block of colour and to have areas where the paint doesn't quite come up to the edge of the mask (opposite of stencilling where you want to have solid colour and crisp edges).
Another method is to not make a sharp edged mask, if once you have made the black (or whatever colour) mask you then use another tool to replace areas of this with a different colour (using a brush such as a Chalk effect that would make a pattern) you can then recreate the mask minus those areas.
Once I have a nice looking marking which looks slightly irregular and battered then I can adjust the layers opacity and merge this marking in with the hull.

Enhancing textures with bump maps and geometry.
This can be done internally in some other paint packages by applying an emboss effect but since Satori (or at least my old copy) lacks this I normally create a bump-map and then in MAX create a box (of the same size as the texture) to which I then apply the "unenhanced" texture and bump-map and then render a combined version. This can have some rather pleasing results, though the greater the difference this makes the more I wonder how much is my work and how much is down to the people who programmed MAXs rendering.
For some things though such as bumps it is actually easier to model them than to try to create a bump-map for them and so in this case I create my box and then add the bumps/lumps/details to this. I then use Boolean Union to combine all the meshes and apply the "unenhanced" texture and bump-map with planar mapping to this combined mesh.

Combining palettes/textures.
The more texture-palettes you have in an OPT the larger the OPTs filesize will be and so from that perspective it is a good idea to minimise the number. There can also be problems where slightly different shades are produced when different textures are reduced in colour depth, something which can be solved if the textures are set to use the same palette. There are two ways to go about this.
You can simply save the texture-palette for one of the textures and then load this into all the other textures which are of a similar colour (e.g. all hull sections, all textures on a wing, etc.). This will generally work quite well and should make things that should be the same colour be the same colour.
Alternatively you can combine the textures temporarily into one large texture which is then reduced in colour depth and sliced apart again into its component textures. This will ensure that all the textures that are cut out of the larger temporary texture will have the same colour palette and that the colour-depth reduction has been applied in the same way to all of them.

Multi-part textures (and self-illumination)
One way to both minimise the number of textures used (which can be useful if you are approaching the maximum number permitted) and the number of texture-palettes is to leave textures combined and set up the texture mapping so that only the appropriate part of the texture is used for each purpose. The advantage of this over slicing the larger texture apart again is that each texture that has self-illumination has a separate texture-palette. This is because illumination is applied to a specific colour in the palette and so if textures shared the palette then this colour would be illuminated in all the textures, even if that was not what was desired.
Therefore if you have three textures which share a texture-palette and each of them has an illumination applied then you would end up with three palettes, but if you have a single texture with all three within it then you would still only have one palette (and you would only need to set up the illumination once in OPTech).
Multi-part textures can also reduce the total filesize another way as with some meshes (especially if using planar-mapping or texturing in OPTech where there isn't a "gizmo" that can be rotated to match the angle of slanted faces) there can be quite an amount of the texture which isn't actually being applied to a face due to the shape of the mesh. Sometimes there can be enough unused space on a large texture that a small texture can fit into that area and thus stop those pixels being wasted. Note though that I haven't actually tried setting up multi-part textures in OPTech.

The disadvantage of multi-part textures is that the more complicated the multi-part texture the more complicated it is to set up the texture mapping and the more complicated it is to keep track of what area of the multi-part texture is being used for what.
This is especially true for me as I have found that the material editor settings for cropping are not saved when I export as OBJ or 3DS from my copy of 3DS MAX 2. This is strange as I thought that I had imported 3DS files with material editor settings for cropping in the past.

Therefore to select only part of a texture I instead alter the settings in the texture-mapping gizmo. This is the same principle as setting up the cropping, but in reverse.

The simplest method, and one which can work very well, is to divide the textures into halves or quarters, so you can just use +/- 0.5 in the texture-gizmo settings. Either because of using the negative value or because of having drawn that part of the texture that way around you might need to flip the texture to correct (which in MAX is just a matter of clicking on the flip check-box).
Example of a four-way split texture (Calamari Cruiser Hangar Console).

The more complicated method, which can be useful when the proportions of the required texture would not fit well with the allowed values or where there would be a large part of the texture not being used due to the shape of the mesh, is to create a texture with lots of parts of various sizes. As said before this would be quite simple if you could set up cropping in the material editor but it is possible to do this in reverse.
Rather than cropping the texture down to fit the area of the gizmo you can instead rescale the gizmo so it is as much larger than the part of the mesh you want to texture as the whole-texture is larger than the part of it you want to use. For example if the whole-texture is 256 wide and the part you want to use is only 200 wide then you would copy the texture-mapping gizmo value into Calculator, divide by 200, and then multiply by 256. You can then move the texture-mapping gizmo around (in effect sliding the texture around) until you've overlaid the part you want.
Example of a texture split in a more complex manner.

One useful tip is to NOT try to set up the texture mapping with the final texture, or even the rendered guide. The final texture will all be a similar colour, which is why they can share the same 256 colour palette without looking bad, and the rendered guide will have fuzzy edges. You would be much better advised to go over the rendered guide with areas of flat colour and then apply this simplified texture to the model. This way you can see how things are lining up and see the result of fiddling with the texture mapping gizmo size and position more easily. Add blobs of colour to the texture to make each areas asymmetrical so you can be sure that things are orientated the correct way.
Template texture for the Dominator Interdictor neck.

Something else I can't emphasise enough is, to quote Darth Vader, to "Not be so proud of this technological terror you have constructed." It can be quite fun fiddling about with the bits of model for the multi-part texture and finding a really good way of fitting them together nicely. What is not so much fun is when you realise that because one part of the model is several times smaller than another part that the smaller part will have be too small on the multi-part texture. This is not so bad if you can just rescale the texture, since the texture mapping is proportional it makes no difference, but if one dimension is already the maximum of 256 pixels and so you have to split the texture into two (for example a 256*128 into two 128*128 which could then be rescaled to 256*256 each) any work you have done on setting up the texture mapping would be lost.

Another useful tip is that I have found that when exporting as a 3DS and converting to OPZ I can have textures listed more than once in the OPTech Transparency / Self-Illumination and have found that the cause (or at least one cause) is where I have set up different parts of a mesh with different submaterials but have then decided to use the same multi-part texture on all these parts. Since this same texture is being referenced by different materials it seems to be listed the multiple times. This would not occur when using a DXF as no texture mapping information is in the file and not occur when using an OBJ as the textures would be being reapplied in OPTech.
This is not a major problem as only one copy of the texture is saved to the OPT file (checked by converting the OPT back into a 3DS) but it is simple to solve, all you have to do is select all the faces using the submaterials that are sharing the same texture and apply the same single submaterial to them all. The faces will all turn the same colour but since the definition of what part of the texture to use is in the mesh rather than the material editor settings this will make no difference to how they look textured. You can then edit the list of submaterials in the material to only have the ones used.
In fact you may as well deliberately risk having the problem as it is simpler to select groups of faces for applying the texture mapping if each group has a different submaterial ID and for a more complex mesh this might outweigh the bother of the extra step of having to then change these to a single submaterial and edit the submaterial list.

Splitting one texture into multiple textures
With a large mesh such as a starship hull applying a single texture across it would produce a rather blurry result as each pixel of the texture would be spread across a rather large area. One solution to this would be to make a symmetrical texture and then tile it multiple times and this can produce good results as long as the texture does not have large obvious features, a texture which is "just" a hull plating pattern can be repeated without this being too apparent but with one which has Calamari Cruiser (or Minbari Cruiser) like swirlies it would be more obvious.
It should be possible with most meshes though to select groups of faces within the mesh which would "divide" it up into regular sections (halves, quarters, sixths, eighths, that sort of thing) and would therefore allow a large texture to also be split to match these. Hopefully these will mostly be 256*256 or 256*128 rather than needing to use anything much smaller to fit with the divisions in the mesh.
The process would be to first look at the mesh, decide how you are going to split it, and then add up the size of the textures for the various sections to determine how big the large texture will need to be. Next you would create the large texture which if not for the limit on texture sizes would have been able to be applied to the entire mesh rather than needing to be split. If you are texturing outside of OPTech and this would be simple to do you may want to apply this large texture to the mesh to see how it looks and to get UVW mapping gizmo values.
Next you would render a wireframe of the model which can serve as a guide for cutting the different sections out of the texture. These sections should then be resampled to "legal" sizes. These can then be applied.

Deciding on the Level of Detail to include in the Texture
Sometimes you might find it better to make some changes to the texture you are creating rather than following your sources completely accurately. There are two possible and opposite reasons for this.

The first reason would possibly apply if you are creating a ship (especially a starship) which has only been shown in a comic. Much of the time a comic artist's style, although there are artists who draw ships which look almost like technical drawings, does not include large amounts of hull detail as they prefer to make a clearer more dramatic image. Although this looks good in a comic if you, as I did with the MC-90, only have the same level of detail then it can look too plain when playing XWA.
In this case you might be advised to add some extra details such as panelling, panel lines, or other variations in hull tone which, although not being so distinct or obvious as to change the general look of the ship's hull, would make the ship appear less flat and simple. Make allowances for the artists drawing style and the technique being used (Cam Kennedy's painted Dark Empire panels are more wash and tone than line and detail) and make allowances for how large the ship is on the page and so how much detail could be "missing".

The second reason would conversely possibly apply if you manage to find some nice large photos of the model (which is preferable to shots from the film as in the film there can be lighting which substantially alters the look of the ship, for instance the Calamari models are white and orange but in RotJ they appear more blue-grey and brown) which show a lot of detail.
There is only so much detail that can be included in a 256*256 size 256 colour texture before it begins to look messy, and there are only so many 256*256 textures that can be included in an OPT before the filesize increased to the extent that the loading time begins to become irritatingly noticeable. Even leaving filesize aside there is of course the limit on the total number of textures and the limit on how many segments with their own individual texture you can divide a hull (or similar large element) in to before it becomes impractical.
So in this case you might be advised to not include some of the smaller details visible in the photos as having them would decrease the general look of the texture rather than making it appear more detailed. You may also be advised to save occasionally as a JPG / BMP to confirm how the texture will look at the final size as there can be a difference between this and how some art packages (such as Satori) display it while you are working on it.

Of course how much you will need to do this depends on your level of ability and your own style. The more skilled a texture artist you are the more ability you will have to make a texture look interesting without greatly obvious changes or to have a texture with a lot of detail without this looking like a mess. An important thing to remember though is that as long as you are happy with the texture then that is the important thing.

Texturing
3DS into OPTech via 3DSOPZ | OBJ into OPTech | DXF into OPTech | gMAX into OPTech via a converter and 3DSOPZ