alice-teacher Question about Point of View

[Don Slater]

It is true that their are two explicit components to an object, location and orientation. There is an implicit component as well, distance from camera, that allows a model to be viewed in perspective. As a model is moved closer to, or away from the camera, in a 3D environment, we would expect that object to appear to "grow" or to "shrink". This last value (which is 1 in your example) is used to help with the transformation of the 3D matrix which is used to internally represent the object.

I hope this helps. If you want a more in-depth explanation, look for "transformation of matrices in 3D graphics".

Hope this helps, and my thanks to Wanda Dann in helping me put together this explanation.

Later,
Don Salter

On Sep 30, 2012, at 8:15 AM, "Funk, Philip" <P.Funk at snhu.edu> wrote:

>                 Hi All,
> Each object in an Alice world has a point of view comprised of two components: the object’s position in the world (left right, up down, forward back) and the object’s orientation (yaw, pitch, roll).  In addition, there is a seventh number as shown in the picture below.
>                 <image001.png>
>                 Does anyone know what the last number (1 in this example) means and how it is used?
>                 Thanks,
>                                 P. Funk
> 
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