Baking & Texture Work - Endless Trial and Error

Baking

With both the low and high poly models fully completed, I could bake both an AO and Normal map. Originally the plan was to create a copy of both the high and low poly, delete every duplicate on both and then export these as "objectLP" and "objectHP" whilst centered on the grid. This was i could load each individual object in to Xnormals to ensure a perfect normal map bake. The only issue with this process is time management.

You're forced to create huge file structures and with such a huge mass of objects, it gets very hard to think of unique and recognizable names for each pair. With every piece individually baked out and then saved back in to another file structure; each map needs to be dragged in to Photoshop, centered and set to Multiply before merging. As you can tell from that brief over-view, its an incredibly long and grueling task with multiple areas to very easily go wrong.

Just look at what is maybe 10% of the file structure;

Maya 2016 had made incredible steps forward with its baking tools, taking over 80% of the prior required time entirely out. Baking within Maya follows the same steps up until the export. By exploding the entire model with high poly components on top of low poly components, the whole low poly car could be combined as one object and the high poly combined as another. With the low poly as the target mesh and the source mesh set to the high poly, the entire car could be baked out all in one go. Due to the huge tri count after converting the vehicle from smooth mesh preview to polygon, I had to do this in three sections but it still made the process infinitely easier. It almost felt like cheating.

To make life easier, I made a short video on the Maya 2016 baking process and why I love it so much;

https://www.youtube.com/watch?v=co9utaEXpyQ

 The only issue I found was that Maya required me to delete all overlapping faces before baking and after multiple crashes from the sheer amount of objects, I managed to corrupt Hypershader. To this day, it's still broken and i cannot apply textures in my Maya scene.

An example of the partially exploded vehicle before baking;

First Texturing Pass

Texturing was by far my weakest point so this required endless trial and error until I got a decent end result.

To start with, I took the UV snapshot of the vehicle before loading this in to Photoshop as a 4k texture. Looking back and forth between the Maya file, I selected each main component and created a colour map within Photoshop. This was an incredibly long process due to the complexity of the mesh but after multiple hours, I had every key different material/ component set to a unique colour and made it very easy to select components on the fly with the marque tool for easy texturing. I did this with both the gun and turret before carrying on forwards as colour maps could be used for almost any texturing process. It created a very nice starting point.

Gun;

  

Vehicle;

As this is an original concept, finding fitting colours for each segment was a complete nightmare. With the colour maps completed I created a new layer and tried multiple base colours until i found something fitting. To add some slight variation, i overlayed an ambient occlusion map on roughly 20% opacity. I know this is against the fundamentals of PBR but having it so low, it simply made some colour variation, preventing the texture from looking too flat.  

 I found that colour values between browns, blues and reds allowed for a very nice variation without making the vehicle seem unfitting for the mad-max style. I tried to stay as far away from greyscale as possible, always using a slight blue or brown colour contrast in even the dullest of parts.

Part way through creating these textures, I realized that it would be a much more effective use of my time to move to another software suite, making the most out of A3D by learning future PBR texturing methods. The only worry with this is that I would have to create an entirely new texturing workflow consisting of constant trial and error until not only I arrive at a suitable quality, but in an easily repeatable process that could be applied to any other asset within a decent time frame.

With basic colours worked out, I could use it for reference up until the finished project. It may seem like a fairly large time sink but having the modelling completed by week 4 provides me with almost two months to develop a new workflow and further increase my understanding of PBR. 

 

The UV'ing Process

The Uv'ing process was quite awkward. In Maya 2015, i would almost exclusively use the unfold 3D tools, allowing me to simply select the areas of the mesh that require seems before selecting the unfold 3D tool to project what would be near a complete UV. For any areas that caused me issues, I could use the old planar projection method or unitize/ sew the edges. This is especially useful on cylindrical objects that would otherwise would take an incredibly long time to UV.

Using Maya 2016, this process took far longer than it should have originally. The new UV tools seem to be incredibly hit or miss; distorting the unfolded UV's beyond recognition when attempting to UV within the university labs yet unfold some objects perfectly once I follow the exact same steps at home. From this, i had to avoid lab computers and UV exclusively at home.

After much trial and error, i found that the problem could be brought down to two different areas;

1. Maya 2016 can disable the 3D unfold plugin between software sessions, in some situations even disabling it mid-Uving. This can be re-enabled in the plug-in manager but seems like quite an oversight by Autodesk. With this disabled, the software reverts to the legacy unfold method whilst is entirely useless in comparison to the newer iterations.

2. Maya 2016 struggles unfolding multiple combined meshes. This is why I found that the UV tools worked best when i became quite dubious of them as this mindset made me UV only tiny sections at once. Simply UV single meshes or duplicated meshes at a time seems to entirely fix this for me but I have seen others attempt this and the UV'ing process still fail.

With 2015, any uneven UVs could be mostly fixed with the secondary "unfold UV tool". You simply needed to select the faces that were un-even, select this tool and drag your mouse to the side. In Maya 2016 this tool has been replaced by a paint brush that doesn't seem very effective in the slightly. All it does it adjust the UV scale, forcing the other UVs to increase in size too, repeating this process until you are left with nothing beyond a larger version of your original uvs.

There may be a trick to this but i found the best option to be to entirely avoid the basic tools and move straight on to bonus tools. These UV tools seem to work as an improvement over the 2015 tools, working in roughly the same way except for a few bugs; mainly if you attempt to UV an object using bonus tools and select off it, i found that it made that object impossible to UV using this method. A workaround though was to duplicate any object i did this to, uv the duplication and delete the old one.

Sure there may be a fair bit to read here but this was the required learning process just to UV my vehicle and gun. With this i decided to put all the main vehicle UVs on a single sheet whilst putting the gun, gun mountings and gun ammo on another, allowing me to swap this out in the future if required.

The great game of tetris to organise these UVs was nowhere near as troublesome as you would expect. I started by scaling all the UVs to a size that i thought would roughly fit due to past experiences and placed the Largest UV pieces in first, followed by the awkward shapes and filling in the gapes with the more generic shaped UVs.

With this finalized on time with my work scheduled, it has left me with a huge portion of time to work on both the texturing and blueprint methodology. 

The Full Low-poly

As the low poly was almost entirely constructed by the time the high-poly was finished, each and every component simply needed to be fully optimized whilst having the excess geometry removed, the only area about this process i haven't yet covered was the need to smooth each edge of the model before selecting each sharp edge to apply an edge hardening. With this completed, i could simply keep one of each piece of geometry, deleting all mirrored parts and begin the Uv'ing process.

Take this as simply a showcase of the low-poly topology and optomisating although some edges still have the crease tool enabled. This doesn't effect the model in the slightest but the uv'ing tools, we'll get to that in the next section. I found that the crease tool and unfold 3D tools don't exactly mix. E.g, the bonus tools unfold tool cannot detect the differance between a previously creased edge and a cut, making for a very long winded process.

Ideas and Concepts Presentation

The presentation for week 3 was to showcase our ideas, concepts and recieve feedback but as i had already created the high-poly and most of the low poly, it drew quite a large crowd, providing me with a huge sum of feedback once i began displaying the topology. This wasn't part of the marking criteria so was only done in the Q & A once i had finished the five minute presentation.

All in all i believe it went very well and i was able to take the feedbackand use it to heighten the drive shaft, make hte vehicle look far more interesting and add in the final touches of usability.

Now for the slides;

And for the matinee;

During thee presentation, i used this as an excuse to give a full breakdown of what i wanted in the final cinematic, starting with my name and job occupation on the opening slab to the final zoomout showing the vehicles title on the old highway sign.

https://youtu.be/NsH4Dxcz7Gw