Monday, October 06, 2003

I've spent the last couple of XSI sessions enveloping and re-weighting the moose. The first BIG lesson I learned, is never to staighten your chains before enveloping. Its not enough to draw them with the natural bend, you must keep that bend otherwise you may find that the joint bends in the opposite direction. I discovered this happens when applying a stored action. Its a good idea to store an action of the IK hierarchy so that you can always return to the default pose. Just make sure you have a slight bend to those joints!

I used inclusive bounding volumes to help with the point assignment on the envelope. This made the weights correct on most parts of the moose. There were only a couple of problem areas that I had to reassign points by hand, the jaws caused a problem, the points where the top and bottom jaw meet were too close, I just zoomed in really close and reassigned locally.

Another thing that was quite handy was a custom toolbar that I setup to switch between the wireframe view of the polygon moose and the shaded view of the subdivision moose, so that I could easily switch and test the subdivision model's behaviour. (The envelope is applied to the polygon model, not the subdivision model, this will allow you to animate the polygon with a better refresh rate than if you were to animate the subdivision model). Its actually easy to set up these custom buttons, don't be afraid of scripting, its really just drag and drop. See Tutorial number 25 "Scripting, Repeating Commands" for steps on how to do this.

In getting ready to animate the moose, I've added his eyes. The lesson I learned here, is when creating clusters make sure you have only the points you want selected... I wasn't watching and ended up with some a large offset using the object to cluster constraint, then I realized that the cluster contained additional points to what I thought. Two places to look out for this on the Main command panel, just below the name of the object, the points will be listed by number. On the Status bar at the bottom left of the screen, XSI will tell you how many points you have selected.

My friend Wotomoro, gave me a "recipe" for an eye rig. Use a Null that is constrained to a one point cluster on the head. Make the null (rename it Left_eye_Rig) the parent of the eyeball and the eyelid. Make the pupil the child of the eyeball.

The cigarette is made in three parts. The main part is simply a cylinder with a texture, the ash part which is another shorter cylinder, randomized a bit to give it an ash look, and another even shorter cylinder that is placed between the ash and the cigarette which is the amber (you won't see this until the moose drags on the cigarette, when the amber will change color to orange/red). I painted the vertices on the ashes rather than using a texture, how to do this is perfectly described in the user guide "Shade.pdf" on page 283 "Painting Colors on Vertices".

Now that I'm ready to animate, I'm going to do Tutorial 8 "The Walk Cycle" to prepare myself.

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