Mar 19 2006 | 12:42 pm

hope someone with trig or linear algebra knowledge can clarify this for me

seems like for years Ive stumbled on deriving the xyz cordinates of a

cylinder's tip so I can bind it seemlessly to other shapes as arms or

tendrils. this patch shows my appraoch to the problem and can be aded to a

gl.sketch environment, it uses jasch's rotatexyz to attempt to bind a sphere

to a cylinders end, I just cant get it to bind when xy and z are actively

rotating, I use a half black half white texture to make the cylinder half

invisible for simplicity, the shape orient command is scaled and moded into

pi phases

it seems like the shape orient and the xyzrotate just arn't in the same

coordinate system, and that there is some constant attenuation that needs to

be made to get them to agree,

siggraph site has these equations but I dont know how to translate math

matri in my head anymore let alone into max, can someone drop me a patch or

mod mine so I can jump this hurdle get back into the art of things

Z-axis rotation is identical to the 2D case:

x' = x*cos q - y*sin q

y' = x*sin q + y*cos q

z' = z

( cos q sin q 0 0)

Rz (q) = (-sin q cos q 0 0)

( 0 0 1 0)

( 0 0 0 1)

X-axis rotation looks like Z-axis rotation if replace:

X axis with Y axis

Y axis with Z axis

Z axis with X axis

So we do the same replacement in the equations:

y' = y*cos q - z*sin q

z' = y*sin q + z*cos q

x' = x

(1 0 0 0)

Rx(q) = (0 cos q sin q 0)

(0 -sin q cos q 0)

(0 0 0 1)

Y-axis rotation looks like Z-axis rotation if replace:

X axis with Z axis

Y axis with X axis

Zaxis with Y axis

So we do the same replacement in equations :

z' = z*cos q - x*sin q

x' = z*sin q + x*cos q

y' = y

(cos q 0 -sin q 0)

Ry(q) = (0 1 0 0)

(sin q 0 cos q 0)

(0 0 0 1)

max v2;