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shreyas_potnis
15th March 2003, 10:08
how dou you sync dm's and ssc's? like in many of UnconeD's presets (circuit city). i tried hard but couldnt get it. the ssc seems to move rotate in some other direction. then i tore down unconed's preset and found that is rotation around x axis is 1 in the dm, then it is -1 in the ssc. this worked for one axis, but when more than one axis had rotatio non-zero, then it doesnt seem to work.
can someone explain?

mikm
15th March 2003, 13:36

UnConeD
15th March 2003, 14:44
You need to make sure both the DM and SSC work in the same camera space. Most superscopes still use the approach of putting an object at (x,y,z) rotated around rx,ry,rz and keep the camera at (0,0,0) looking at the z axis.

A 3D DM however works completely different: the objects are at a fixed position in the world, and the camera moves and rotates around them.

So if you want to synchronize a DM with a SSC you need to make them use the same model. Otherwise the rotations will mean totally different things in the scope and the DM.
It's easiest to alter scopes to match DM behaviour.

Basically if you're good at visualising 3D objects and rotations it should be obvious what you need to do. First you calculate your object regularly, then you add its position to its coordinates (if necessary). Then you need to use the reverse order of rotations in the scope, and use the opposite angles (which basically means flipping the sign on the sines, not the cosines, because cos(a) = cos(-a) ).

If you don't understand why this is necessary, you don't really understand what you're doing with a 3D DM and scope... try visualising what happens when a DM is calculated and a scope is rendered. Remember that rotations always happen around the world axes, which is why the (z,x,y) order of rotations for a DM is the best approach (it's the best equivalent of how a human body looks around).

shreyas_potnis
15th March 2003, 16:09
frankly speaking I understood some part of this ( well I understood the copcept anyway ) . I havent tried this but...i think I will get this right

anubis2003
15th March 2003, 16:26
If you are talking about basic synching, search the forums. There are three basic ways:
Using getosc and getspec
Using counter variables
Creating a pseudo random number generator.

shreyas_potnis
16th March 2003, 10:25
oh, no thats just basic stuff.. :)
ok, i sort of got that right. when the ssc has postion as (0,0,0) and sin(rx,ry and rz) is negative, it works. but as soon as I change its position, the preset looks ugly

UnConeD
16th March 2003, 13:34