3 ms·
Suppose you are standing anywhere on planet Earth, and you look at the horizon (not up, not down, so 360° of choice). A normalized quaternion encodes your posi
by p0nce 8y ago
Suppose you are standing anywhere on planet Earth, and you look at the horizon (not up, not down, so 360° of choice).
A normalized quaternion encodes your position on the planet + the direction you are looking at on the horizon.
It also encodes the rotation it would take to go from one such observer to another.
- deleted 8y ago[deleted]
- jrootabega 8y agoSo it's your position in space (3 numbers), your orientation (another 3 number vector), except instead of 6 numbers it can be reduced to 4? Stargate was wrong?
- naavis 8y agoEncoding your whole orientation would require 3 numbers. You are restricted only to the horizon, so one number is enough.
- numerobis 8y agoOrientation is only two numbers, since a unit vector does the job? So, three numbers in total?
- deleted 8y ago[deleted]
- p0nce 8y agoThat's why it doesn't encode free orientation.
- breatheoften 8y agoDoes this assume the earth is a sphere? Can you keep the elegance of this coordinate encoding with convenient transformation operations and define somewhere a mapping from the quaternarion encoding of position into a non-homogenous oblate spheroid encoding like WGS84 ...?
- p0nce 8y ago> Does this assume the earth is a sphere? Of course, speaking about Earth is just for the mental image. > Can you keep the elegance of this coordinate encoding with convenient transformation operations and define somewhere a mapping from the quaternarion encoding of position into a non-homogenous oblate spheroid encoding like WGS84 ...? I don't understand the question.