My responsibilities regarding the models created for the Astronautics Simulation Project are researching, modeling and texturing
Neptune's moons:
Neptune has 13 known moons with a wide variety in sizes, shapes and orbits. After doing my own research on all of them I decided to model just five (the largest ones) since very little is known of the rest, mainly because of their tiny size. I thought it was not worth to model these tiny moons (for now) because the player will not get that close to Neptune (some of them are orbiting very close to Neptune's thin atmosphere) and, from the distance, he/she won't be even able to distinguish them. If this project goes any further, more moons can be modeled and maybe even take some artistic license since there's no visual data available for many of them.
The ones I did for this stage of the project are
Triton, Nereid, Naiad, Larissa and Proteus.
*All the scientific information in this post has been taken from NASA website.
How did I create the assets?
As I mentioned above, the first thing I did was a research about all Neptune's moons and its phisical characteristics (mainly: color, shape and texture). Once I decided to work on the five biggest ones, I started creating the shapes. Triton's was just a simple sphere, so I just created a sphere polygon in Maya and then textured it. The case of the other moons was different as they all have a organic specific shape, so I decided to use Zbrush to define the volume since this software allows you to work in a very intuitive way (which I prefer because of my clay sculpting background). Once all the shapes were fairly finished in Zbrush I exported the assets into Maya as .obj files so they were ready for me to create the UV maps (see details below), apply the materials and the textures.
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| Triton's first test with pinching of the texture on the poles |
The textures were found mainly in Google (links provided in the texture images caption), except for Triton's which was extracted from NASA website. Only Nereid's and Larissa textures were not changed -only the color information was- (the first was ready to be applied on a sphere shape, the second worked well on a cube based shape), all the rest were modified in Photoshop so they could be applied on a sphere-based shape with no stretching or pinching on the poles. It was the first time for me solving this problem, so I had to do some research and found this tutorial. I followed it with good results (see images below). Once I checked all the textures were working properly on the models I created the bump maps by deleting the color information from the color maps so I could get a grey scale image and then modify the white and black balance (bump information was also modified in Maya by using the bump depth button).
*A note about the color maps: all the moons but Triton have mainly a grey scale color applied. This is due to these being rocky volumes with no atmosphere, plus there is no color information about them. Triton is different since it has gas and a very thin atmosphere wich, by action of the sun light, reflects the colors you can see in the texture provided by NASA below.
As for the materials applied, all the moons have Lambert except for Triton, for which I used a Phong material. This allowed me to play with the reflection and specular properties of the moon since one of its main features is it reflects 70 per cent of the sun light due to its surface being covered with a large ammount of ice.
Finnally I created a light point into the Maya scene to emulate the sun light so I could nicely render all the assets. All the images can be found below (renders, wireframes, UVs and textures).
1.- Triton
Triton is the largest of Neptune's moons. As a curiosity fact, it is the only large moon in our solar system with a retrograde orbit (it orbits in the opposite direction of it's planet rotation).
Triton has a cratered surface with smooth volcanic plains, mounds and round pits formed by icy lava flows. The ammount of ice on the surface reflects 70 per cent of the sun light that reaches the moon.
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| Rendered 3D final asset - created in Maya and Photoshop |
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| Wireframe Sphere display (Maya) |
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| UVs spherical mapping (Maya) |
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| Real Triton's color map (source: NASA) |
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| Color map applied (created in Photoshop) |
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| Bump map applied (created in Photoshop) |
2.- Nereid
Nereid is one of the outermost of Neptune's
known moons and is among the largest. Nereid is unique because it has
one of the most eccentric orbits of any moon in our solar system (it requires 360 Earth days to make one orbit).
No other information regarding phisical characteristics could be gathered, so I took some artistic licence to make this moon.
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| Rendered 3D final asset - created in Zbrush, Maya and Photoshop |
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| Wireframe display (Maya) |
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| UVs spherical mapping (Maya) |
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| Texture applied (image source here) |
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| Color map applied |
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| Bump map applied |
3.- Naiad
Potato-shaped Naiad orbits close to Neptune. The small moon circles the planet every seven
hours and six minutes in a decaying orbit; Naiad may eventually crash
into Neptune's atmosphere or be torn apart and form a planetary ring.
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| Rendered 3D final asset created in Zbrush, Maya and Photoshop |
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| Wireframe display (Maya) |
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| UVs spherical mapping (Maya) |
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| Texture applied (source here) |
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| Color map applied (created in Photoshop) |
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| Bump map applied (created in Photoshop) |
4.- Larissa
Larissa is another of the small moons found near Neptune's faint ring
system. It is irregularly shaped
and heavily cratered.
Larissa's orbit is mostly circular, but it is slowly spiraling inward
and may eventually impact Neptune's atmosphere, or the gas giant's
tidal forces may break Larissa apart to form a planetary ring. The moon
orbits Neptune in about 13 hours and 20 minutes.
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| Rendered 3D final asset - created in Zbrush, Maya and Photoshop |
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| Wireframe display (Maya) |
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| UV mapping (Maya) - automatic mapping + manually move and sew |
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| Texture applied (source here) |
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| Color map applied (created in Photoshop) |
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| Bump map applied (Photoshop) |
5.- Proteus
Proteus is one of the largest of Neptune's known moons. It has an odd box-like shape and if it had just a little more
mass it would be able to transform into a sphere. Proteus orbits Neptune
about every 27 hours.
Proteus is irregularly shaped and heavily cratered. Circling the planet in the same
direction as Neptune rotates, Proteus remains close to Neptune's
equatorial plane. Proteus is one of the darkest objects in our solar
system (reflects only 6 percent of the sunlight that hits it).
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| Rendered 3D final asset created in Zbrush, Maya and Photoshop |
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| Wireframe display (Maya) |
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| UVs spherical mapping (Maya) |
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| Texture applied (source here) |
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| Color map applied (Photoshop) |
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| Bump map applied (Photoshop) |
Nereid is one of the outermost of Neptune's
known moons and is among the largest. Nereid is unique because it has
one of the most eccentric orbits of any moon in our solar system (it requires 360 Earth days to make one orbit).
Potato-shaped Naiad orbits close to Neptune. The small moon circles the planet every seven
hours and six minutes in a decaying orbit; Naiad may eventually crash
into Neptune's atmosphere or be torn apart and form a planetary ring.
