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jit.bfg euclidean origin

April 9, 2006 | 11:23 am

Hi all,

I have a question about the jit.bfg origin message. When for example using the distance.euclidean basis and outputting a normalized matrix of 256×256 like in the helpfile, I would expect to see black at the point of origin, and white at the farthest point. With an origin of 0 0 this looks correct (black at upper left corner).

When setting origin 128 128 or autocenter 1 I would expect a black hole in the center of the matrix, similar to the illustration on page 473 in the jitter tutorial. However this doesn’t happen, origin 128 128 produces the same result as origin 0 0.

Evidently there is something I have overlooked, could someone please clarify how jit.bfg thinks?

Thanks

Mateusz

http://www.westerplatte.net


April 11, 2006 | 4:15 pm

> I have a question about the jit.bfg origin message. When for example using the distance.euclidean basis and outputting a normalized matrix of 256×256 like in the helpfile, I would expect to see black at the point of origin, and white at the farthest point. With an origin of 0 0 this looks correct (black at upper left corner).
>
> When setting origin 128 128 or autocenter 1 I would expect a black hole in the center of the matrix, similar to the illustration on page 473 in the jitter tutorial. However this doesn’t happen, origin 128 128 produces the same result as origin 0 0.

Aww come on. Is this such a stupid question that nobody bothers to answer, or is it too difficult for anyone to dare an answer?

Why won’t the origin message move the euclidean distance origin in the way I would expect? Slap me in the face, please…

Mateusz


April 11, 2006 | 8:44 pm

Nope. It’s a good question. The issue is that the original author is
no longer working for C74, and I haven’t had a chance to verify and
look at the code to offer an explanation or confirm it is a bug. I
hope to get to it soon, but no need to harass us. There are higher
priorities: e.g. Mach-O UB port.

Otherwise, you *can* center by specifying an origin of -4.83,-4.83 it
looks like. I’m unsure as to why this is the scale…but will
investigate. Thanks for your patience.

-Joshua


April 11, 2006 | 8:53 pm

Btw, in the meantime, I might suggest the very clear jit.expr method
for calculating euclidean distance, normalized to the range -1 to 1
for each axis: expr "hypot(snorm[0] , snorm[1])"

-Joshua


April 13, 2006 | 1:33 pm

Thanks Joshua!

Didn’t mean to harass… Just trying to understand jit.bfg properly. The jit.expr methoed does just fine in the meantime.

All the best

Mateusz


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