Monday, 14 March 2011

Transcription - A Furry Bear at Last

Its taken a lot of tweaking, some painful fur combing in Maya, and then scrapping that and just doing it all in Photoshop, and now the furry bear is completed.

Now I know what you are all thinking. How does a bear go from flat n' grey to gold n' fluffy!

Well simply adding fur to the bear and changing the colour and length etc gives you something like this.

Which is mostly great, except for the visible seams where the edges of the UV shells are on the UV map and the hands particularly have too much fur.

Now to fix this, the most important attribute in the fur is the fur direction. This has to be painted in Maya. Little did I know at the time, how unintuitive and time wasting it would be.
Every time I did a test render, the fur direction map, would not always update, and so I would make changes, render, see no changes, try again, and so on. Switching renders or Saving As seemed to fix this. Although that's not what I found unintuitive.

The display fur preview (the 3D view), was set at 128. Any higher and Maya just couldn't handle displaying such dense fur in the preview. But that's fine, as there was just enough fur to see what I was painting. The point is that, I set the image map resolution size to 1024 by 1024. Both in the fur settings and the painting settings. So as far as I was concerned, it was painting at a decent resolution.

After a lot of painting, and still having seams and random fur splodges that wouldn't go away I decided to look at the image file it was creating. I almost wanted to laugh at what Maya had done, but at the same time I wasn't in a good mood. Take a look at this.

A 1024 resolution image, with a 128 pixel size (and with a lot of random splodges). The display settings for Maya actually have an effect on how it renders, because the file that is painted is stuck at that resolution, no matter what actual resolution you change the map file to.

This was when I decided to paint it in Photoshop. It took me a while to work out what the black and white values represented in terms of fur direction.
Here's a diagram I made to show what it all means.

White and black are down, and all the levels of grey are the 360 degrees of rotation. Simple really. With that knowledge, I painted this map.

And together with a base and tip colour map, and a length map, I got the final bear.
Fur Length Map

Fur Base Colour Map

Fur Tip Colour Map

Here are three images showing how some of the variations in length.

I might still need to make the eyes more visible, but its basically done.

So what I've learnt from all this is that fur isn't really that hard after all, but Maya fur IS hard.

I was still in for one last surprise though. I wanted to apply the fur to a bear with some animation, to see how it all deforms.
I created a new scene and imported the bear rig with out fur. Applied the fur preset and attached the map files. I then baked the map files and Maya had one last change to make. When baking the files, the images were up-scaled to the intended 1024 resolution and smoothed out. There was only one problem with that. I didn't want my images to be changed. If you look back at my direction map, you will see that the body is half white and half black. (still technically the same rotation value). Up-scaling the images, blurred the crisp line, (producing grey in-between) thus producing a seam.

Also when baking, the clumping seems to be more noticeable. You will see that the squares of clumping are quite noticeable in the video.

Although I'm not sure about the clumping, I do know how to fix the image up-scaling problem.

Anyway, for all those good enough to have listened to me for this long, and maybe even learnt something you didn't know before, I leave you with a video of the bear running with fur.
And just for fun, he is being chased by an invisible cannibal!
(might need to go to fullscreen HD to see the benefit of the fur)

I copied the animation of one of the invisible cannibal characters run cycles, and quickly adjusted some of the curves. It's not a perfect transition, but for the purposes of this test its good enough.

While all this fur stuff has been taking place I have also been blocking out the whole animation. The idea is to have everything roughed out first. Then I will go back and refine every shot one by one. In theory I should be able to finish this within a day or two (the blocking out) and present a sort of pre-vis pretty soon.
And from then on, its animating like crazy!

A Flock of Pixels


  1. Very impressive Ethan! Looking great so far. The fur really makes a difference - its definitely a huggable bear now :)

  2. A really comprehensive post, Ethan - which, even though technical, manages to convey your enthusiasm - and your bear is indeed huggable now! Well done.

  3. Lovely! :) Keep the posts coming, so we can see what you are up to!

  4. Thanks for all the positive feedback!

    I can say that the fur was worth the effort!

  5. "he's so flufy I'm gonna dyyyyeee!!!" (Agnes in Despicable Me) so true in this case :D
    It looks sooo cuuute!!! (:D

  6. Oh also, will you have eyebrows? I'd really suggest adding the element. just simple scuares parented onto head joint with generic blend shapes. At least in my case ( which is somewhat similar to yours: a live toy) it just boosts the expresivness, and when I need that extra kick in conveying a point, eybrows are the thing :D :D

  7. Well done Ethan. An intelligent approach to your characters set up. This could be part of your technical paper.