|
 |
I'm having trouble with a parameterized calculation in three forms
((T*P)/2)*pow((clock - index(Start))/index(Duration),2)
(P*T*T)*pow((clock - index(Start))/index(Duration),2)
and
T*P*( (clock - index(Start)) / index(Duration) )
index(T) is calculated by a macro which takes a 3d vector T
_TICK_ is defined in another macro.
#macro index(T)
#local Seconds = T.x*3600 + T.y*60 * T.z;
_TICK_*Seconds // where _TICK_ is (final_clock - initial_clock) /
animLen
#end
I passed various elements of the calculation to a debug statement, and the
problem seems to arise in the (clock - index(I))/index(D) portion, the result
being that my Delta_T is about 10,000 times larger than it should be.
which shouldn't work
When I run the same calculation with set values as below
(5*1080/2)*pow((clock - 0)/index(5),2)
I get exactly what I should get, as confirmed by my pocket calculator with
various different values.
I have three files illustrating this problem in a zip file I'll upload to p.b.a
test.pov illustrates the solution that works while test3.pov illustrates the
problem
I've been rendering with the following command line:
+a0.03 +ki0.0 +kf1.0 +kfi1 +kff600 -D -GA
and encoding with mencoder at 60fps
any insight on this problem would be appreciated
Post a reply to this message
|
|
|
|
"Anthony D. Baye" <Sha### [at] spamnomore hotmailcom> wrote:
> =?UTF-8?B?IkrDqXLDtG1lIE0uIEJlcmdlciI=?= <jeberger@free.fr> wrote:
> > Anthony D. Baye wrote:
> > > #local Seconds = T.x*3600 + T.y*60 * T.z;
> >
> > Shouldn't that be a "+" before "T.z"?
> >
> > Jerome
> > --
> > mailto:jeb### [at] freefr
> > http://jeberger.free.fr
> > Jabber: jeb### [at] jabberfr
>
> It's correct in the files. Just a typo in the post.
>
> A.D.B.
It seems that the problem lay in the fact that the operations aren't precomputed
by the separate macros but, rather, dropped in to form a larger equation. The
result is that I had to parenthesize EVERYTHING in each macro, so that the
proper order of operations could be preserved.
It makes sense when I think about it.
the troublemaker line was in the eClock macro
_TICK_*Seconds
i changed it to (_TICK_*Seconds) and voila!
I also put encapsulating parentheses around each of the three formulae in Timer.
The Timer macro is now self-limiting and additive so that the line:
rotate (Timer(1, <0, 0, 0>, <0, 0, 5>, 1080) +
Timer (3, <0, 0, 5>, <0, 0, 10>, 1080))*x
creates a timeline for rotation about the x axis where the first five seconds
are spent accelerating to 4 revs/sec and the last five are spent rotating at a
constant 4 revs/sec.
Comments?
A.D.B.
Post a reply to this message
|
|
