Timeline for If a 3D vector represents a point, how can it have a length?
Current License: CC BY-SA 3.0
23 events
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| Jun 1, 2017 at 23:29 | comment | added | Andy | A vector (or any tuple of xyz values) doesn't "only represent a point" - maybe all the vectors you've seen so far were representing points, but vectors can also represent many other things like surface normals, the velocities of objects, etc. | |
| Jun 1, 2017 at 13:30 | answer | added | Loki Clock | timeline score: 1 | |
| Jun 1, 2017 at 11:54 | comment | added | Marco13 | @MohammedNoureldin My answer mainly pointed out a detail that might cause a wrong understanding, so I wonder whether you intentionally accepted my answer, or did not actually want to accept the answer by Alexandre Vaillancourt, who answered earlier and (regarding the key point of the question) gave the same information (Of course, the decision is up to you, I'm just wondering...) | |
| Jun 1, 2017 at 1:10 | vote | accept | Mohammed Noureldin | ||
| May 31, 2017 at 21:40 | comment | added | Andy | @MohammedNoureldin I think you should change the accepted answer to gamedev.stackexchange.com/a/141816/99768 since it explains that points and vectors are transformed differently, and the current accepted answer doesn't mention that. That's the only conceptual difference that game developers need to worry about. | |
| May 31, 2017 at 20:51 | answer | added | Stephan | timeline score: -1 | |
| May 31, 2017 at 19:50 | comment | added | Polygnome | @Peter I'm afraid I have to disagree with you. Standard algebraic definitions of a vector pretty much mean its not a point. its often useful to consider it as such since position vectors can be used to represent points, but they are not points. "5 meters" is always a distance (or length), it will never be a time or color. It often useful to use different symbols - I personally would never use (5, 5, 5) to denote a vector, I'd always use (5, 5, 5)^T (T for transposed) or use proper column-representation where supported. Because saying a vector is a point introduces inaccuracies. | |
| May 31, 2017 at 19:39 | comment | added | Peter | @Polygnome A vector means whatever it means, which can be a point, a displacement, the real components of a quaternion, or an infinite amount of other things. Saying "(5,5,5)" is always a displacement is just valid as claiming "5" is always a distance. | |
| May 31, 2017 at 17:36 | vote | accept | Mohammed Noureldin | ||
| Jun 1, 2017 at 1:10 | |||||
| May 31, 2017 at 10:13 | history | edited | Vaillancourt♦ | CC BY-SA 3.0 |
Fixed a confusing typo.
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| May 31, 2017 at 9:11 | answer | added | Polygnome | timeline score: 8 | |
| May 30, 2017 at 19:56 | answer | added | Marco13 | timeline score: 20 | |
| May 30, 2017 at 17:46 | history | tweeted | twitter.com/StackGameDev/status/869610970611687424 | ||
| May 30, 2017 at 17:27 | history | edited | user1430 | CC BY-SA 3.0 |
added 12 characters in body; edited tags; edited title
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| May 30, 2017 at 15:06 | comment | added | Polygnome | It doesn't. It represents a displacement. It only points to some point if you consider it an position vector, in which case it denotes the displacement from (0, 0, 0). The length of such a position vector is the distance of the point to the origin. | |
| May 30, 2017 at 13:53 | comment | added | Ruslan | Vector representing a point is also known as radius vector. It is merely a vector from origin to the point of interest. | |
| May 30, 2017 at 13:38 | comment | added | Mohammed Noureldin | @Theraot, Thank you very much, that sentence helped me a lot! | |
| May 30, 2017 at 13:34 | comment | added | Theraot |
Normalized in the context means a new vector that preserves the Direction but has Magnitude of 1. That is, the Normalized vector is created by scaling the original vector.
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| May 30, 2017 at 13:30 | history | edited | doppelgreener | CC BY-SA 3.0 |
added 1 character in body; edited title
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| May 30, 2017 at 13:22 | comment | added | Peter | Consider a scalar, also known as a number. It can mean an absolute value, a difference, a percentage, etc. | |
| May 30, 2017 at 13:20 | answer | added | Vaillancourt♦ | timeline score: 36 | |
| May 30, 2017 at 13:15 | answer | added | Ian Young | timeline score: 5 | |
| May 30, 2017 at 13:10 | history | asked | Mohammed Noureldin | CC BY-SA 3.0 |