This is my very first post from Game Art class, [so go easy on me!]
The key on the top was a mere exercise, nothing more than that...[if you're saying "That key looks familiar..." that's because it's from the movie Pirates of the Caribbean: Dead Man's Chest!...my favourite of the 4 movies]. The key on the bottom is the final assignment, with texturing and lighting as well.
Assignment Description:
The key here [no pun intended...] was to create a low poly model of a rusty key [300 tris] with textures [colour map, normal map, and specular map]. Both of these keys are around 300 tris, and I went insane on the texturing [especially for the 2nd one]. Keep in mind that this is created for a Game Engine [so we really have to be considerate on the number of poly's being used, the size of the texture map, the normal map and specular maps, etc.] Game art is quite different from Production in terms of the way the project is executed.
How It Was Made:
I started with a cylinder for the hole in the key, extruded outwards and pulled the vertices, added edge loops, blah blah blah [you know the drill!] However, it was a little challenging to create this using only 300 tris [polygons with 3 sides]. The placement of each vertex is carefully thought out in order to create a smooth mesh with a few amount of polys.
Because Game Art requires everything to be done in REAL-TIME [not rendering], most things work differently...for example, a bump map won't be seen in real-time, whereas a normal map will show up in a real-time game engine. Also, you can't just blindly create a model by adding edge loops, faces, extrusions, etc. because the more number of polys, the more resources and computing power the game engine requires. That is why the poly count is EXTREMELY important in Game Art.
So the colour map pretty much speaks for itself [the areas of rust, dirt, metal, the numbers and symbols, scratches, etc.]. The specular map is added to give more realism in terms of the lighting [for example, in the rusty and dirty areas, the object won't be as shiny as it is in the cleaner areas. So if you observe the bottom image, only the "cleaner" areas are highlighted and shinier than the other rusty, dirty areas].
Finally, the normal map is used to add a little depth to the texture [you can see it very well in the bottom image...the numbers and symbol look as if they have been engraved on the key]. Without a normal map, the textures may look beautiful, but will still appear "flat." Finally I baked an Ambient Occlusion map from a high poly version of this key, and transferred that map onto the low poly version, to capture SHADOWS, adding more depth to the key.
Final Words:
This assignment was quite fun to do and I'm glad it turned out so well!
It's rendered using Maya Software with a standard 3 point light setup with 1 negative light for the contact shadow.
I'll try to post some more game art related stuff soon!
Thanks :)