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sugardave
09-26-2006, 06:42 PM
I've just begun playing around with Alice. I started with the tutorials, though the second one didn't seem to be functioning correctly. Then, I loaded a new world and added the fairy and the duck prince to it.

Now, I want to have the fairy point at the duck prince. I've tried various parts of her arm and the point at method. By far the most dramatic effect is achieved using the whole arm. However, the problem is, she always points away from the duck prince. Just behind her, actually. I can have her facing away from the duck and she will turn to face him, but pointing has her totally screwed up.

I saw something about objects that are too close in proximity can cause unpredictable behavior, but this occurs even if the fairy and the duck are very far apart.

I'm hoping this is some stupid noob mistake, so go easy!

DrJim
09-26-2006, 07:50 PM
Wish it was a "simple" mistake. Not sure I can explain clearly but look at the pictures on pp. 44-5 of the text by Dunn, et al, if you have it. Basically "face" works by matching the orientation of the "front" faces while "point" matches the orientations of the coordinate axis of the objects. What makes it not so simple is that these are geometric abstractions and are not always where you might think.

In your case, try pointing with just the arm and, if it is pointing in exactly the wrong direction, just point and then turn the arm 1/2 revolution.

Probably going to goof on a technical level in describing the "problems" when objects get close, but again see the Dunn text for examples. When parts of two objects are allowed to overlap, what appears on the screen is that the objects are merged and the combined "outside" surfaces are shown. This can be OK, funny or artistic if you want it to be but sometimes is just plain unexpected.

Jim

sugardave
09-26-2006, 08:24 PM
I realized what you are saying about 15 minutes after I posted when I loaded the white rabbit instead of the fairy and used one of his legs to point. Then it was dinnertime ;)

I do not have the text, unfortunately, but am looking for one.