need help

[nightelves]

ok i'm probably gonna hang around this forum quite a lot because i'm a bit noob with this program so far. i've started doing some of the exercises in the textbook and hit a roadblock on question 2-1a. how can you make the cheiser cat move towards a chair without it moving underground?

[DickBaldwin]

Many of the details of your question are unclear. However, if you would like to post your world that is having the problem, and provide a text description of the nature of the problem, I will be happy to take a look at it and see if I can give you some advice.

Dick Baldwin

[DrJim]

Before you get too involved trying to write code for that problem, note that the problem itself only asks for storyboards. By all means try to do the code if you want - but be aware you will probably need techniques beyond what have been introduced in the first two chapters.

I suspect your immediate problem comes from the fact that the "move to" method always moves the "center" of one object to the "center" of another. The "center" in this case is just the zero reference point for the local coordinate system and need not be at the actual center of mass for the object. For "people-like" objects, it is often (but not always!) the center of the bounding plane that moves along the ground (translated - between the person's feet :) ). You can see where the center of an object is by clicking on it and seeing where the colored axis intersect. (See the text before the problem for some examples.)

In the case of the Cheshire cat and the "Chair" object - the "center" of the cat is in the middle of his body while the "center" of the "Chair" is at the bottom of the chair's legs. Hence when the cat "moves to" the chair, its bottom half goes underground. Try using the "ArmChair" for a more natural sequence.

[nightelves]

so theres no way of making the chair and the cheiser cat move naturally and dickBaldwin concerning your question heres the storyboard

a child's game: alice, the white rabbit, and the cheshire cat enjoy a game of musical chair in a tea party scene. one of the characters yell "switch" and they all run over and the character standing next to it is eliminated from the game (moves away from the table).

can you make this one and i'll compare my results with you thanks m8

[DickBaldwin]

Of course not. As I said before, if you want to send me what you have, I will take a look at it and try to give you some advice. However, I'm not going to write your assignment for you.

In any event, DrJim has already identified the problem with the cat becoming partially buried. It has to do with the fact that the moveTo method (and the moveToward method also) attempts to align the centers of the two objects.

The center point for the Cheshire Cat is in the center of the cat's body. I couldn't find the chair in the gallery, but from your description of the problem, it sounds like the center point of the chair may be on the floor beneath the chair.

If so, when the two center points are aligned, the cat would be about half buried.

So, you will need something a little more clever than just moveTo or moveToward to bring the two together without the cat becoming half buried.

Dick Baldwin

[nightelves]

yeh so wats ur advice for making the cat not buried to the ground.

[DickBaldwin]

My advice will be forthcoming after seeing the work that you have already done.
Dick Baldwin

[DrJim]

My suggestion is that you read the section of the text immediately before the problem. Pay particular attention to the concept of "yaw" and the difference between the "move to" and "move toward" commands.

This is an exceptionally well written and well illustrated section of the text and explains some very important concepts in 3D animation. Learn them - don't just ask for help.