(Above: Diffuse map for body textures) This is what the model looks like once I had applied the first layer of base colours to it. I worked in very much the same way you would in any painting, first applying a base for then to add details onto and then final add all the little touches and damage/rust to it to show Sprockets character as an abandoned old robot.
The next step was to add all of the surface detail, the main thing being all the linework to depict the overlapping plates that made up a lot of sprockets main body work, both on his head and his body. Instead of just drawing flat lines I also added a lighter line alongside it to help contribute to making the plates seem more 3D even at just the diffuse stage. I think this will contribute towards the normal and specular maps later on.
This is the final look to sprocket before I begin to apply all the wear and tear to him. I wanted to keep the main bodywork to him a consistent and basic colour, as the thought process behind him is that he would have been a mass produced unit available to most people and businesses in maintaining their properties, so I wanted to keep things simple. However areas such as the paint markings on him I wanted to match his asymmetrical body parts in that it would have been damaged and re painted over, over the years so that it no longer resembled its original patterns or meanings.
As the title of the project suggests, things like rust and damaged metal will play a big part in the surface detail in all of my characters to show how long they have been left to their own devices, away from the maintenance of man. Using a faux media effect brush in Photoshop I painted in the rust and grime in the areas that I wanted to be most affected. At the start I pretty much just plastered it all over, but then went around deleting it out of areas I didn't want it to be prevalent in, as well as fading some colour down. Areas such as Sprocket's jaw I wanted to be really obviously affected by rust so that it appeared to resemble facial hair on his, which I think combined with his bleary eyed expression adds to his character.
The overall body once I finished applying wear and damage to it. One thing I have gotten back in terms of feedback in regards to the rust is that its too consistent throughout. I need to work on breaking it up a bit, making it appear more sporadically and naturally along the plates, and to also appear in different shades in areas to break up the overall colour scheme. This is something I will consistently look at adjusting until I finalise this character as its something I want to get spot on.
To finalise the diffuse (for now) I added surface decals to it to make give him the manufactured look. Things such as serial numbers, and warning striped on his power pack to give him that authentic feel. With the specular map, I spent a long time focusing on highlighting the areas in between the rust and alongside the edge of his Armour plates to really catch the light, while a lot of areas damaged and scuffed to appear a lot duller. I also took this into account with the normal map, making it only really bump off the outlines of the plates and the areas of rust that were really prevalent on his bodywork, so that it gave the rust a peeling look that is seen on really derelict machinery.
Final textured version of Sprocket: Though I am largely happy with how Sprocket looks, from a lot of feedback I received there are several areas I need to revisit at a later stage, such as the rust detail and how it appears on the individual plates (needs to be more targeted instead of all over), what areas the specular effects and also refine the normal map down somewhat. Once I have fully rigged this guy and have him all ready for exporting into engine, I will go back to tweak these areas and polish them until I am satisfied with the final look.