Gas Station Random Project

Recently I have been working on a Gas Station. Didn't really plan to do this, but it's already pretty far on in development. Here are some screen shots:

The model is built in high-res with the aim of its surface data being baked down to a low-res game mesh for the final scene. With the gas pump and some items around it being finished, I have already started to construct the low res geometry, which the last image shows.

Also, just a random update on the helicopter model from my previous post; this model is still being made, and has progressed a bit from where it is shown there, but not by enough for me to bother posting any news on it yet I don't think. I also have an urge to make a kitchen scene for some nice interior design renders, but I probably shouldn't start a 3rd project on the side....

Lord Beritra - AION 4.0: Dark Betrayal

So naturally while I'm supposed to be working on this months art challenge set by Polycount forums, I decided to veer off track today with a strange urge to create a model of 'Lord Beritra', the 'Forth Dragon Lord' from the MMORPG, Aion. Probably because I was listening to the games' soundtrack. 

Considering I started it today, I have gotten quite far with it. It already has most of its normal maps from ZBrush as a first-pass. They haven't been detailed or cleaned up at all yet. I actually built the model over Xiahou Ba's body, retopologising the hands and face once the rest of the body was built to match the lower polycount.

Here is my progress so far. This render is done in Marmoset Toolbag 2, as this is my goal for this project I think.

Maya 2016 Normal Map Bug

Technically this is not a bug. It is just a different default way that Maya 2016 now loads textures compared to all previous versions that can be frustrating when you don't know what's happening. Here is a demonstration on my State Alchemist project when I first brought in his normal maps for testing:

Beta normal maps applied to a Phong Shader in Maya 2016. Viewport 2.0 (Default), DirectX11 Render Engine. (OpenGL Render Engine produces the same results.)

As you can see, on the left the normal maps do not evaluate as expected. If you simply went through the paces of adding the maps on in Maya 2015 or below, you would immediately see the result shown on the right. 

At first it is not entirely clear what is wrong with the maps, but luckily I had seen this before in Unreal Development Kit a few years ago while in university, and so had an idea of where to start looking.

You can see the thread on my university project here to see the same issue in the UDK game engine:

http://catburglarsgame.blogspot.co.uk/2012/02/udk-normal-map-research.html

Essentially the maps have been forced into a colour-managed environment, thanks to all the new viewport colour controls introduced in Maya 2016. As a result, the colours of the maps have been slightly altered internally, and so do not render as expected.

Luckily there is an easy fix!

Above is the issue. You may notice that the texture panel in the attributes editor to the left looks a tiny bit different to Maya 2015 now. Here's what has to be changed:

Changing the colour space to 'Raw', we are telling Maya not to enforce its own colour management on this texture file, and therefore it will work exactly the same way as it always used to in previous versions. However, it is still somewhat annoying to now have to remember yet another extra step during material setup....

Now you can see the problem has been resolved. As far as I am aware, there is no option to make Raw imported textures the norm unfortunately. Let me know if you find a way though!

Xiahou Ba Progression - Difference Between Baking Normal Maps in ZBrush & Maya

While I continue to develop my rendition of Xiahou Ba from Dynasty Warriors 7/8, I have been running some tests with the texture data I'm getting back from the high resolution sculpt in ZBrush. The UVs are holding up very well which I am pleased with, but I noticed some of his normal maps have a little to be desired still; they often seemed a bit faint or flat in areas, compared with the true 3D sculpture.

Looking into this problem online for a while, I started reading posts from people saying ZBrushs' normal map baking is very weak and they don't even use it for this reason. Instead, they use their original 3rd-party application for this job, such as Maya, Modo, Max, or XSI.

(Softimage XSI no longer exists as of 2015 by the way)

With this idea, I decided to bring a high resolution mesh from ZBrush (Sub-division Level 5) into Maya, along with its 'game-ready' counterpart. I then used Maya's 'Transfer Maps' tools under its 'Rendering' tool-set to bake the surface information from the high resolution mesh to the low resolution mesh in the form of a normal map. The results certainly are different, and it does seem Maya does produce slightly superior results:

This GIF animation shows the actual difference between the bake from ZBrush, compared with the bake from Maya. The frames are spaced 2 seconds apart, so give it time.

To accompany this, I will provide you with the high resolution bakes themselves. The top image shows the results split next to eachother, and the bottom images show the full results side-by-side.

From studying the differences between the two map bakes, both completely unadulterated, you can make some general observations straight off the bat:

• Maya's bake contains stronger reds and greens, increasing the overall intensity of the normal map compared to that from ZBrush.
• ZBrush by enlarge has a cleaner resulting map straight away, with less tangent distortion around the neck and bottom of the torso on the map. However it is important to point out at this stage that Maya can fix these issues with tweaking of its options; it is simply the case that ZBrush appears to be more optimised for this kind of work from the get-go.
• ZBrush appears to have possibly distorted the baked results very slightly, most noticeable on these bakes around the nipples and under the arms. Despite saying that however, I'm still not 100% sure it really is distortion, and it could be Maya that has distorted the results instead and that they simply just look a bit better. This would all be down to the target search area set up in each software package accordingly.

In other words, it might be that Maya produces better, stronger results overall, but they require more tweaking around the edges and more tweaking of the options before each bake than ZBrush. It would theoretically be possible to also intensify and adjust the normal map bakes from ZBrush to get better results also, however this process can be very difficult to do without breaking the continuity of the maps (seams can suddenly become violently visible if you simply increase the contrast on the maps).

These GIF animations shows the results working on the actual model. Especially pronounced on the greyscale images, you can see that the baked map from Maya gives a much greater sense of 3D than that from ZBrush.

I would not call this testing conclusive. While Maya holds better results than ZBrush for this model, the same might not be true for other models. Also remember that both of these maps are made using somewhat standard settings in both applications, and so further tweaking of the options may produce better results and worse results in both software packages respectively. However the issue with ZBrush baking normal maps to look much flatter and less intensive is something that has no options to modify. For this reason alone, I think further testing with Maya might hold better results for my future projects.