Nothing really fancy in the patch, It's some kinda video sampler, that take very short capture from webcam and displays it looping wich increase the feeling of this very tiny instant ...

duno how to explain

well I try to do

the same very simple math in actionscript and puredata and get different results...

PD

1.5707963267948966 -> cos -> print

output: -4.37114e-008

in flash

trace(Math.cos(1.5707963267948966));

output : 6.123031769111886e-17

I think it's because the number is cut when too long or something,

is there a way to fix this ?

thanks

hey !

I've put my hands on a kinect, and thanks to Matthias Kronlachner I've pluged it to PureData with pix_openni.

So I receive points with XYZ translations,

and I want to transform that in rotations for a rig.

I'm no expert with such things. but I tryed something out with trigonometry :

a being the hand and b being the shoulder

BC = (a.x-b.x);
AB = (a.y-b.y);
AC = sqrt((AB*AB)+(BC*BC));
BD = AC - AB;
YY = atan(AB/BC)+atan(BD/BC)
X = (YY*180/PI)*2;

this gives me in degree from 0 to 360 the angle of my arm, I then just give him XY, XZ and ZY translation and get RX RY RZ in return.

But when I apply it as a rotation to a cube, movements don't match ...

So I guess that's not the right technique. I'm reading something about matrices, but I don't understand it quite well ...

so maybe somebody can tell me if I'm on the right way, and maybne explain me a bit

thanks for reading,
cheers

hey there !

I have a simple question : how can I do like in php a variable variable

• see http://www.php.net/manual/en/language.variables.variable.php

---

my problem is

I have an abstraction(called MASTER) that outlet a number (the stereo mix volume), lets call it RESULT

I want this number to be sent to different OSC adress like such

layer1/position/value RESULT
layer2/position/value RESULT
layer3/position/value RESULT
layer4/position/value RESULT

Right now I have my 4 message box each containing the message and a $1

but I want to be able to control how many layers so I used [until]

simplified it looks like

[MASTER]
[trigger bang float]

the float goes to the right inlet of a [pack f f]
then the bang go to the [until] and put the result (0, 1, 2, 3, ...) in the left inlet of the pack

the pack outlet to a message "layer$1/position/value $2"
and that works perfectly

Problem is, I wand to be able to multiply the value of each layer to a different number(contained in a list for example)

if Master output let say "2";

right now 2 is sent to all the layers

but I want that :

layer1 value is 2*($1 of another list)
layer2 value is 2*($2 of another list)
layer3 value is 2*($3 of another list)
...

but I'd have to write $1 wich doesn't work...

I think it's not really clear what I'm saying ... but thanks for reading !

well I found a euler/quaternion/euler calculator online and after compare his results with mine, it appears that the part I have wrong is the RZ in case of gimbal lock

maybe someone can telle me wich part is wrong

RX = ((sin_X*sin_Y)*sin_Z)+(cos_X*cos_Z);
RY = -(sin_X*sin_Y)*cos_Z+cos_X*sin_Z;

Z = Math.atan2(RY,RX);
Z *= RADIANS;

cheers

http://pastebin.com/RQgwaC1J

I made a patch to fix gimbal lock on PD but I still have wrong moves,

can someone telle me if the patch is wrong ?

or if after gimbal fix following rotations

X 160 Y 90 Z 267

with Y to be the base

you get

X 0 Y 90 Z 106

thanks

thanks baby cot ! very helpfull

though maelstorm I now realise thant when turned back in degree it fits

thanks cheers

Hey !

thabnks for your answer, but is there a way to easy make bigger precision ?

I'm trying to make a patch against gimbal lock for 3D rotation from kinect translations.

so I have my XYZ angles, I convert them to a matrice, check condition for gimbal lock and convert back to degree,

but while all of this there is a lot of cos sin & tan added and multiplied wich create very different results from for example flash and the part I'm intrested in for gimbal lock fix are very tiny precise numbers ...

so ? any lutions ?

http://lists.puredata.info/pipermail/pd-list/2012-04/095889.html

does that mean I'm screwd ?

actually I just found that

http://en.wikipedia.org/wiki/Gimbal_lock

wich is I think my problem, I'm trying now to understand how to write a solution in PD