This is good stuff!
I like the fact that it's down to Earth... er.. not the best expression in the context...
I mean that they are fairly un-complicated. I'd probably have succumbed to the
temptation to add more detail to the meshes; but it would have proven a mistake;
because the more unique the shapes, the more recognizable, and pretty soon
you'd realize they are exactly 4 shapes.
I think the level of detail you have is just about right for there being 4 types.
Guess we'll have to CineMutize them
Only thing I don't quite feel comfortable with are the bright specular textures.
I know nothing about asteroid geology, but I've a feeling that even the most
metallic of asteroids are covered in dust, at least. I don't think any of them would
look like shiny metal; but that's what they would look like with bright speculars.
Also a bit worrisome is to see color in the speculars. I hope you know what
colors you're using and why. Only metallic specularities have color, and the
color has to correspond to diffuse color. More specifically, diffuse color, for
any metal, is approximately the square of the specular color, toned down.
Say gold, for example, is yellow in specular.
Let's say some gold alloy is 0.9, 0.8, 0.6 in specular. Let's call that "specular
chroma", to give it a name.
Its "diffuse chroma" would be the square, or 0.81, 0.64, 0.36. Got it?
Now let's say the surface has very few microcavities, so that its specular
ratio is like 0.9.
Then, final specular color would be specular chroma * 0.9; and
final diffuse color would be diffuse chroma * 0.1.
If you don't observe this relationship for metals, you end up with psychedelic
materials.
For non-metals, specularity is always white; or rather "non-chromatic".
For mixed materials, the truth lies on a line between the two points above,
but never too far off that line. (Well, except that you can have a diffuse material
of one color mixed with a metal of another; but then you need to apply other
math rules to that, namely the mix-in diffuse color must obscure the specular
by the blending ratio in which it mixes with the metal's diffuse.)
And the other rule is that in no channel of no texel of no texture should diffuse
plus specular EVER add to more than one.
CineMut enforces all the above; but if you're targeting standard shaders you
have to observe the rules at texturing time.
Easiest way to do it would be to use separate xcf's for metallic and non-
metallic contents; then combine them by blending them based on yet another
procedural mask.
So, for a metallic xcf you'd have an albedo base; then duplicate layer, set to
multiply, save copy to square.png. Delete the duplicated layer; then Load
as Layer square.png; rename as diffuse_chroma. Then you generate a
procedural mask, monochrome, load it as layer, rename to "specularity".
Set the diffuse_chroma layer to normal blend 100%, invert the specularity
and set it to multiply, then save copy as metal_diffuse.png. Undo the
inversion of the specularity, hide the diffuse chroma, so that specularity
now multiplies the background texture, and save as metal_spec.png.
For non-metals you have a diffuse base and a specularity mask only.
Specular is simply the specularity mask.
Diffuse is the inverse of the specularity mask multiplying the diffuse base.
Call them diel_diffuse.png and diel_spec.png.
Now you generate another procedural mask, and use it to blend the two
diffuse and the two speculars, separately, into diffuse.png and spec.png.
Finally, you'd have another diffuse color base for mix-in, representing
dust or rusts or whatever, and a monochrome mix-in mask, pretty dark.
So, you multiply the diffuse.png AND spec.png by the inverse of the
mixin mask; and the new color base by the mask (un-inverted); then
blend the result of the latter in ADD mode to diffuse.png. Done.
Easier to do in Blender than in Gimp, really; with compositor nodes.
But besides all that, your specular masks should be pretty dark. Most
of the reflectivity would be diffuse, I would think. Bright specular is
pretty much a synonym with shiny metal. And whatever specularity
you do have should be very low shininess.
In CineMut, I'm planning to do something with detail textues to have
sparkly christals. Basically, dots that shine bright but only at some
angle, so that as you move relative to a rock or dust surface you see
fleeting sparkles.
So, no luck yet getting them in-game? I'm thinking, Vegastrike has
like two or three kinds of asteroid fields. Some are disabled I think.
Could it be that you picked one that is not used to replace yours for?
Or were you importing your roid as ships just to look at them?