Making of Cambird, Part Two.

Boning the Cambird.

I start by building a deformation armature throughout the bird’s body. Three bones in each toe, two in each leg, three including the head for a backbone, another for it’s stomach , beak. Many for the tail and some for the bird’s crest.

Then I make that armature into a modifier of the bird’s skin. The skin will bend along with the bones.

In order for this to work well, each vertex on the skin’s mesh needs to know which of the bones are supposed to guide it’s movement. This is organized by vertex-groups. Each bone has a vertex group named after it, and those in the vertex group are affected by the bone the group is named after.

The automatic guess-level default for that isn’t terribly great, so it takes quite a lot of tweeking and fine-tuning using the weight paint system to get the skin actually responding to the bones properly.

Blender even crashes as I do so, but I’d saved recently. All is fine.

Once all the deformation bones are in place, and the bird’s skin seems to follow that well, I add some more bones for kinematics.

Rigging the Cambird.

It can be hard to position a character as you’d like if you have to work up forward in the bone tree from the root every time. So I add new non-deformation bones and tell the system to draw those as rings and loops and targets, then add constraints to many of the deformation bones to have them track the target bones.

I give this a test, tweek, revise a few doomed experiments, then eventually animate a test flap.

It’s time to try out the motion-blur that’s going to be essential to getting the wings to buzz and look fast, giving the character the speed it needs to appear to have.

This doesn’t look great at all with the wings deforming as they are. The top of the wing clashes with the bottom, giving unpredictable effects.

So I remake the wings, deleting the bottom layer, making them zero-height, hoping that will work better.

It doesn’t really, because the actual probables was the displacement map, pushing the body’s mesh out through the wings.

Still, I get a decent flap animation going, then correct the texture.

And that gives me an idea!

Experimenting with cloth-simulated wings.

I delete the birds wings entirely, and decide to try running them as a separate object connected to the bird and running the cloth-physics simulator. It might make my little bird look a bit bat-like, but it’s supposed to be an alien bird anyway.

Worth a try.

I build some new wings, apply the armature to them and apply a cloth simulator to the deformed mesh.

I move the wing armature so that it affects only the leading edge of the wings, and then try a test animation.

It’s hard to get the bones to effect the whole wing well, so I add another set of wing-bones towards the back of the wing, and experiment more with ways to get those to map well into the wing shapes.

This still works pretty poorly so I add yet more wing-bones in, spanning the length of the wing between the two main wing-bone lines.

That makes things look much better.

So I build some more test animations, even sitting the cambird on a perch.

Then I try those test animations, with and without the cloth.

The cloth-simulator adds little, I feel, and certainly slows my computer down to a crawl.

I decide the cloth isn’t worth the effort and rendering time. So do without it.

Which means joining the wings-object back to the main mesh.

Building a better texture

The texture all looks a little rubbish really, all solid-colours, no texture.

So I find a bunch of pictures of parrots, and pull the feather-textures from those pictures instead. Tweaking until it looks about right.

Adding the camera

The cambird is a cybernetic organism, and needs it’s cyber-camera added. This is just a very simply model with a picture of a lens projected on it and a plastic camera backing on the rest.

I try it in her stomach/chest, but it doesn’t really work well there.

After the test render, and without the screencast running, I end up moving it into a ring around the crest. But the next time we see Cambird, she’ll be in her introductory scene.

Music

The music is a track called “Living”, by Coco, whose Jamando page can be found at http://www.jamendo.com/en/artist/1551/koko

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