I had never used fur before so used my "Mastering Autodesk Maya 2011" to read up about it. In the book it gives you an example of a dog and explains how to add fur and paint the different attributes. This was a good starting point for me so I could then develop further.
I firstly did a basic test to see how the outcome would look if I used a preset built into Maya. I used the Calico Cat preset but changed the base colour and tip colour to the same texture file that Sarah Strickland had created for the skin of the cat. Below was the outcome.
This was not the outcome I was quite expecting but then I started to adjust some of the settings such as polar and inclination to get the fur going it the expected direction. The main way to control the fur was to keep playing around with the settings. I had to make the fur density more and the fur opacity higher and eventually I got something that resembled the cat fur I was looking for.
It still needed a lot of work so I continued to play with the settings so that the fur wasn't so straight and was more fuzzy. I wanted it slightly shorter as well rougher. The thing that really stood out though in every test I did was there were some bald patches that would not disappear. I tried increasing the density but the fur did not appear in the bald patches.
After some research online about this problem I started to look at baldness maps. I didn't want the fur on the inside of the ears and I could paint it so there was fur where there currently wasn't. The white mesh would be areas where there is fur and the darker the area, the less fur there would be. I tried to use the paint attributes tool to literally paint on the bald areas but it didn't work. There are some black spots in the image below that would not be painted white no matter what I did.
This lead me to create a custom baldness map. I started with the texture map and took it into photoshop to make it greyscale. There were some areas on the legs where I wanted fur but the area on the map was dark so I had to make some adjustments. When I added this map to the model, below is an image of how it turned out.
There are still some areas (like the bottom of the left leg) where it is still bald for no apparent reason. With that aside, with the baldness map, I was not very happy with the outcome. Some of the areas which are completely bald do not look natural. On the face for example, as the baldness becomes less, it looks strange because you see random strands of fur when the fur should gradually get longer instead.
To change this, rather than attaching a baldness map, I applied a map to the length. This meant all the darker areas would have shorter hair and the lighter areas would have longer hair. It was a lot easier to create because all I did was greyscale the texture map and adjust the contrast and brightness levels. This was the final map:
I had to continuously keep testing the brightness of the map to get the correct length for the fur. Once I was happy I attached it to the model and this was the outcome:
It needed some more tweaks but it was heading in the right direction and looking more like natural fur.
After experimenting more with the settings, I managed to achieve a balance of most of the attributes. The final fur image is below.
There are still some baldness issues on the front leg but I cannot find a way to get rid of it. I have researched on the internet and even posted on some forums but no one seems to know why it could be happening. I had to admit defeat on this problem as I don't think I will be able to resolve the issue anytime soon. Instead I decided to turn my attention to scripting again.
I found a fur script online for a bear and decided to take a look at it. The script is basically a list of all the fur attributes and their values. It was surprisingly simple to me how easy it would be to replicate the fur I created above in a script. The only issue I would have is the base and tip colour attributes because I am using a texture file. If it was a plain colour with set colour values it would be a lot easier but I am not sure how I would be able to add a texture file to the script for others to download. If it was only for myself then I would add a file path into the tip and base colour attributes section.
This is something I will look to develop in the future as to write a script as large as is required to make it work instantly for my model would take a lot of time which I am currently short of. It would definitely something to help me with my scripting skills in the future.
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