The Texturing

Basic Texturing

After entirely finishing my UV sheet, I was able to export a 1024 x 1024 snapshot and then load it in to Photoshop. Before I could begin texturing I had to generate an ambient occlusion texture map. This caused a variety of problems though due to both the huge number of components that makes up the construction vehicle and the fact that to improve on texture quality, I overlaid almost every single mirrored face within the UV texture editor. 

This allowed me far more resolution to work with but also forced me to separate my model in to groups for each major component before I could bake them. Even with all this, after exporting each major component as a FBX and loading them in to x-normals for a faster baking process, the end results still had a wide assortment of errors which forced me to do a lot of tweaking in Photoshop, using the healing brush, smudge tool and clone stamp tool. Once I got to a position where I felt relatively happy with the end results, I placed both the AO and UV snapshot in Photoshop; Snapshot at the top set to screen and the AO placed below as an overlay and could then begin texturing.

At first when beginning the physical texturing, I decided to start with block colours, ensuring that not only could I get all the basic details down quickly and neatly; I could colour code as well as group each component within Photoshop to make it a lot easier to identify which component was which. Although this seemed like a rather good idea at the time, due to corruption I lost the entire block out forcing me to restart with just the AO and snapshot but it did give me a rough idea of what of what colours look best in which locations.

Even though my UVs had a fair few seams in them, I used a few techniques learn within texture dev to make them entirely seamless with very little to no trial and error. By separating the main body with the largest seam in to a separate object, duplicating it and then planar mapping it to a camera view in which the seam is covered, I could then open the ‘Transfer maps’ menu and bake the newly UV’ed body as a the source mesh with the correctly UV’ed body as the target, ensuring that both are visible and ‘Diffuse’ is selected. I had to create a new texture for the newly UV’ed body which was simply a 1024 tiled version of the original body texture but after baking all I had to do was open the newly baked diffuse in Photoshop and erase everything beyond the edges where the seams are located between the UVs. 

As the seams were completed covered within the duplicated vehicle frame, leaving just these edges and then overlaying them over the normal UV texture sheet I had been working on left me with an entirely seamless result. This is a fairly time consuming task so I only used it on crucial areas but it could realistically work for any possible UV seam but it is important to ensure that the UVs are set to the same scale across the entire object or some awkward blurring can occur.

Using a variety of textured I sourced from local pipes, surfaces, early reference and food I began experimenting, creating individual and unique textures for each and every component within the construction vehicle. This may have been un-necessary and have taken far too much time but through the use of an extremely powerful camera, I was able to combine zoomed in segments of just a few texture images together to make a huge number of variations. By selecting each component area using the Polygonal selection tool, I was able to make the entire sheet look incredibly neat which in turn made it far easier to understand once more detailed were added.

It may have taken an incredibly long time to lay down all these base textures but it left me with a nice, un-painted and rather rusty effect across the entire vehicle. Even at this, it still looked quite unfinished in comparison to my original reference photos but I was then able to create a new layer to handle block out colour, putting the base layers on the ‘Subtract’ layer mode, allowing areas of the rust texture to show under the block colour.

At this stage, I wanted to add a bit more detail and depth to each component but due to the texture resolution on most components, it was going to be a very awkward task to incorporate it directly in to the base textures but by created another layer and setting it to bevel/emboss, I could turn down the fill and then trace each component with a near transparent line which incorporated a nice bit of shading detail, making each component look slightly more warn around the edges. This was a fairly quick process but created some rather dramatic results.

I then decided to create a normal map for the wheels to make the thread look more protruding and generally make the wheel look more realistic. To do this, I found one of my reference photos of the construction vehicle’s tire tread and created the basic raised geometry across a flat plane in Maya. After adding a few edge loops and then applying smoothing, I was able to bake the end results to a plane before tiling it across the treat UV area. After applying this in ‘Tangent Space’, as a normal/bump map in Maya, it made the tires pop out a lot more than previously.

The overall texture still needs a bit doing to it in terms of a few decals and I need to erase a bit of the yellow block colour to show through a bit more rust in areas that require it but generally im quite happy with the result up to this point even in a fair fit more work is still required before I can call it a finished product. In the future I do need to pay far more attention to layer naming as I appear to be incredibly messy in this sense, forcing myself to then spend a good few hours afterwards removing, renaming and then combining each of the necessary layers which over-complicates the entire process.

Finishing Touches

The final steps i had to take to finish off this construction vehicle was the generate the specular map, rub away a bit of the colour detail with its luminosity detail to remove some of the more intensive orange shaded areas. With the colour levels more or less correct, I was able to use the sharpen filter on any faded area to add a slight bit more detail to the rough metallic areas. The windows still seemed a little too dirty so i turned down the window dirt layer and the glass effect worked much nicer.

With the model now looking relatively decent, i created a low impact normal map which i combined with the previous map to make each material really stand out. It may be less obvious on areas such as the painted surfaces but the front scoop and other bare metal pieces become crusted and relatively bumpy, really allowing the material to show through.

   

UV Mapping

The Unwrapping

After entirely finishing the mesh, the next course of action was to unwrap every single part of my model, using a checkerboard pattern to ensure that each projection was corrent and not blurred in the slightest. Throughout the previous tasks, i found this to be a rather awkward task, forcing me to spend hours moving around UVs after making each projection just to ensure that no edges were stretched.

This time around, i decided to firly straighten out the angle of any and all of the cylinders within the model, making it far easier to map them directly from the x,y or z axis and to ensure that each projected face was put directly in to scale the second  it was projected, i altered the projection width and height of every face to 100. With oddly angled faces, i still had to tweak the UVs slightly but due ot everything being practically the same scale, i was able to 'Move and sew' the vast majrotiy of faces togather without deforming the UVs, speeding up the entire process greatly whilist also giving overall better results.

After mapping of all these pieces out, it was time to play what is the largest and most awkward game of tetris possible; organising all of the components within the set 1024 UV space. I was able to overlap a lot of mirrors faces due to the symetrical nature of the vehicle which allowed me to have a much high resolution for each area but this has left me with some awkwar semes that i must fill during the texturing stages.

All in all, i think this has turned out quite well. There are some areas that i wish i had sclaed up slightly in comparison to others but the end result should look quite nice if i use every pixel allocated to me. As you can see on the model itself, i may be using a 512 checkerboard which makes the resolution look much lower but throughout the entire model, i cannot find even a single stretched UV.

Once the UVs have be signed off, i should be able to jump straight in to texturing and due to the duplicate faces, it should overall take far less time to fully texture the overall mesh in comparison to other non-symetrical models.