need help calculating x y z velocity from angle

Started by LEN1802 on

Topic category: Help with MCreator software

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need help calculating x y z velocity from angle
Tue, 09/01/2020 - 13:01 (edited)

Ive been making a projectile that chases after the player,which uses the set movement vector block to move.

i have found a formula to calculate the direction from one 3d point to another, which goes like this:

angle = arccos ( a * b / |a| * |b| );
where:
a * b = ax * bx + ay * by + az * bz
|a| = sqrt( ax * ax + ay * ay + az * az )
|b| = sqrt( bx * bx + by * by + bz * bz )

 

and ive also found the way to change that angle into a 2d vector for x and y, which is explained in this document:

https://en.wikipedia.org/wiki/Unit_circle

 

but i dont know the method for turning that 2d formula into a 3d fomula that i can use.

does anyone know how to turn an angle into an X,Y,Z movement vector?

 speed should be variable.

 

Edited by LEN1802 on Tue, 09/01/2020 - 13:01
Joined Sep 2020
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alright, a friend of mine…
Tue, 09/01/2020 - 19:46

alright, a friend of mine whos good a trig gave me a much easier way to do this than i tried to cook up:

First, find both of the objects 3d positions in space. We'll call these position vectors A and B. Then subtract the vectors, B-A. , you do this by subtracting the individual dimension coordinates, like Bx-Ax, etc. We'll call the resultant vector R, and it is a vector that points directly from point A to point B.

Find the length of vector R. sqrt(Rx^2+Ry^2+Rz^2)

Divide each component of R (minus the ^2) by the total length given by that formula. That gives you a vector that point towards B but is only one unit long. Then multiply that unit vector by whatever your desired velocity is and use that as the velocity for the homing thing.

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I'd be damned. That's…
Tue, 09/08/2020 - 20:00

I'd be damned. That's actually a smart way of doing this.