Re: A86: polygons
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Re: A86: polygons
Yeah I get most of it. But, what are "thetaX","thetaY".
I know what the character looks like but what effect does
it have on x and y?
Tnx
> To do 3D rotations you can use matrix multiplication. I frequently get
> this backwards, so be careful:-).
>
> Rotate about the x-axis:
> [[1, 0, 0]
> [0, cos(thetaX),-sin(thetaX)]
> [0, sin(thetaX), cos(thetaX)]]
>
> Rotate about the y-axis:
> [[ cos(thetaY), 0, sin(thetaY)]
> [ 0, 1, 0]
> [-sin(thetaY), 0, cos(thetaY)]]
>
> Rotate about the z-axis:
> [[cos(thetaZ),-sin(thetaZ), 0]
> [sin(thetaZ), cos(thetaZ), 0]
> [0, 0, 1]]
>
> the rotation matrix is multiplied by the (X,Y,Z) coordinates in the form:
>
> [[cos(thetaZ),-sin(thetaZ), 0] [[X] [[Xcos(thetaZ)-Ysin(thetaZ)]
> [sin(thetaZ), cos(thetaZ), 0] * [Y] = [Xsin(thetaZ)+Ycos(thetaZ)]
> [0, 0, 1]] [Z]] [Z]]:
>
> x = (Xcos(thetaZ)-Ysin(thetaZ))*25/(25-Z)
> y = (Xsin(thetaZ)+Ycos(thetaZ))*25/(25-Z)
--
Tercero -- Email: mailto:tercero@busprod.com
"The stone the builders rejected has become the capstone;"
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