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Is there a more general property or class of properties or concept that encompasses the concept of position and space?

It does not seem clear to me that position is the most general property (if it is a property) applicable to an object, so I have been searching for a more general property, or class of properties, which will include the property of position, but I have been unable to find anything.

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marked as duplicate by wolfdawn, Anko, Josh Sep 24 '14 at 2:10

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

  • \$\begingroup\$ Why the downvote? \$\endgroup\$ – user2108462 Sep 23 '14 at 19:57
  • \$\begingroup\$ Yes, position is often used in games. In fact, every game that displays moving objects, needs to keep track of their position in order to display them correctly on the monitor. \$\endgroup\$ – wolfdawn Sep 23 '14 at 19:59
  • \$\begingroup\$ That doesn't answer the question though. I'm asking if there is a more general concept than position. \$\endgroup\$ – user2108462 Sep 23 '14 at 20:01
  • \$\begingroup\$ All that cruft about your discussion with your friend is opinion-based and distracting from the only (marginally?) on-topic terminology question in your post, so I removed it. \$\endgroup\$ – Josh Sep 23 '14 at 20:20
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The more general idea is transformation, which includes a frame of reference and typically rotation. The frame of reference with respect to position could be another object ie. 10 feet above earth's surface at lat X, long Y, or it could be implied to be the world origin (0,0,0). For rotation, we usually use a canonical rotation that is the result of whatever format, say, a model is in, and then the rotation is implied to be offset from that.

Unity actually takes frame of reference from parented objects, such that each item has a local position that is offset from its parent objects. For example, a driver's position is local to their car, and thus the world position of the driver is relative to the car's rotation and position.

This is an important concept because position at any given time can depend on attached objects' current rotation and position. An especially complex example:

Local Cluster -> Galactic Center -> Sun -> Earth -> Car -> Driver -> Driver's Hat -> Spider on Hat

With this scale of simulation, we need to know the driver's hat's position relative to the driver, the position of the driver relative to the car, the rotation and position of the car relative to earth, the location and rotation of the earth, and so on.

Of course, unless you're working on something like Kerbal Space Program, this amount of parenting is unnecessary. Most often we use this to attach clothes and props to bodies and bodies to vehicles.

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  • \$\begingroup\$ Thanks for your answer. Can two transformations disagree as to where an object is, in terms of absolute space? Also, is there a more general way to relate one object to another than position? \$\endgroup\$ – user2108462 Sep 23 '14 at 20:23
  • \$\begingroup\$ Yeah, transformation like @jzx wrote, I think you could start by reading about transformation matrices. \$\endgroup\$ – wolfdawn Sep 23 '14 at 20:33
  • \$\begingroup\$ I believe it's actually called a transform. A transform is the subject of a transformation. Where transformations are methods like translate, rotate, scale, etc. \$\endgroup\$ – MichaelHouse Sep 23 '14 at 20:54
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    \$\begingroup\$ As a designer of a rendering/game engine, the class heirarchy we use doesn't allow a single object to have 2 transforms, and as for relating to other objects... how do you think in the real world ?? "Joe is 10 feet away from me and 15 degrees to the right of the direction I'm facing" is a very accurate relative description of position with your location and rotation being the origin for Joe's location.. the difference between real world and 3D space is that if you turn, joe's position doesn't change, which demonstrates unequivocally that there is another (parent) spacial framework involved \$\endgroup\$ – Ascendion Sep 23 '14 at 22:37

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