weird thingy in flowfield

dklr · Post by **dklr** » Sat Feb 04, 2006 11:09 pm

Why des this flowfield look strange near the "planets"

//locations of "planets"
A0="rnd&#40;2&#41;-1"
A1="rnd&#40;2&#41;-1"

A2="rnd&#40;2&#41;-1"
A3="rnd&#40;2&#41;-1"

A4="rnd&#40;2&#41;-1"
A5="rnd&#40;2&#41;-1"

//masses of "planets"
A6="rnd&#40;.005&#41;"
A7="rnd&#40;.005&#41;"
A8="rnd&#40;.005&#41;"

//distance
D0="sqrt&#40; sqr&#40;x-a0&#41; + sqr&#40;y - a1&#41; &#41;"
D1="sqrt&#40; sqr&#40;x-a2&#41; + sqr&#40;y - a3&#41; &#41;"
D2="sqrt&#40; sqr&#40;x-a4&#41; + sqr&#40;y - a5&#41; &#41;"

//angle
D3="atan2&#40; &#40;x-a0&#41;, &#40;y-a1&#41; &#41;"
D4="atan2&#40; &#40;x-a2&#41;, &#40;y-a3&#41; &#41;"
D5="atan2&#40; &#40;x-a4&#41;, &#40;y-a5&#41; &#41;"

//force
D6="a6/sqr&#40;d0&#41;"
D7="a7/sqr&#40;d1&#41;"
D8="a8/sqr&#40;d2&#41;"

srcX="x + d6*sin&#40;d3&#41; + d7*sin&#40;d4&#41; + d8*sin&#40;d5&#41;"
srcY="y + d6*cos&#40;d3&#41; + d7*cos&#40;d4&#41; + d8*cos&#40;d5&#41;"

Vers=312

Rovastar · Post by **Rovastar** » Sun Feb 05, 2006 9:37 am

I am not sure what you are trying to do but I think you have used atan2 wrong.

atan2(y,x) arctangent of y/x (range is -PI to PI)

Whereas you appear to have used it
atan2(x,y)

So they need to be

D3="atan2((y-a1), (x-a0) )"
D4="atan2( (y-a3), (x-a2) )"
D5="atan2( (y-a5), (x-a4) )"

Here is the full config witha few changes by me.

Code: Select all

//locations of "planets"
A0="0.5*&#40;rnd&#40;2&#41;-1&#41;"
A1="0.5*&#40;rnd&#40;2&#41;-1&#41;"

A2="0.5*&#40;rnd&#40;2&#41;-1&#41;"
A3="0.5*&#40;rnd&#40;2&#41;-1&#41;"

A4="0.5*&#40;rnd&#40;2&#41;-1&#41;"
A5="0.5*&#40;rnd&#40;2&#41;-1&#41;"

//masses of "planets"
A6="0.001+rnd&#40;.001&#41;"
A7="0.001+rnd&#40;.001&#41;"
A8="0.001+rnd&#40;.001&#41;"

//distance
D0="sqrt&#40; sqr&#40;x-a0&#41; + sqr&#40;y - a1&#41; &#41;"
D1="sqrt&#40; sqr&#40;x-a2&#41; + sqr&#40;y - a3&#41; &#41;"
D2="sqrt&#40; sqr&#40;x-a4&#41; + sqr&#40;y - a5&#41; &#41;"

//angle
D3="atan2&#40;&#40;y-a1&#41;, &#40;x-a0&#41; &#41;"
D4="atan2&#40; &#40;y-a3&#41;, &#40;x-a2&#41; &#41;"
D5="atan2&#40; &#40;y-a5&#41;, &#40;x-a4&#41; &#41;"

//force
D6="a6/sqr&#40;d0&#41;"
D7="a7/sqr&#40;d1&#41;"
D8="a8/sqr&#40;d2&#41;"

srcX="x + d6*sin&#40;d3&#41; + d7*sin&#40;d4&#41; + d8*sin&#40;d5&#41;"
srcY="y + d6*cos&#40;d3&#41; + d7*cos&#40;d4&#41; + d8*cos&#40;d5&#41;"

Vers=312

Is that the sort of thing you were trying to acheive?

willrob · Post by **willrob** » Sun Feb 05, 2006 11:44 am

Neither version works for me. This is a flowfield, right? If I select either with the toolbar, it quickly changes to another random ff.

dklr · Post by **dklr** » Sun Feb 05, 2006 12:50 pm

willrob wrote:Neither version works for me. This is a flowfield, right? If I select either with the toolbar, it quickly changes to another random ff.

try updating g-force

dklr · Post by **dklr** » Sun Feb 05, 2006 12:52 pm

Rovastar wrote:

Code: Select all

//locations of "planets"
A0="0.5*&#40;rnd&#40;2&#41;-1&#41;"
A1="0.5*&#40;rnd&#40;2&#41;-1&#41;"

A2="0.5*&#40;rnd&#40;2&#41;-1&#41;"
A3="0.5*&#40;rnd&#40;2&#41;-1&#41;"

A4="0.5*&#40;rnd&#40;2&#41;-1&#41;"
A5="0.5*&#40;rnd&#40;2&#41;-1&#41;"

What is the 0.5* for

Rovastar · Post by **Rovastar** » Mon Feb 06, 2006 7:06 am

I was reducing the amount of random variable range. I though -1 to 1 was too much as you were baising it on x (-1 to 1). I though I the random variable would dominate too much compared to the x or y.

Anyway I was just playing with it.

Did the atan2 thing solve your problem?

willrob · Post by **willrob** » Mon Feb 06, 2006 11:22 am

I'm using the most current version of G-Force 3.1.3 (MaxOSX) and can't get either of these versions to function. Is thee a particular waveshape that triggers this flowfield better than others? Colormap? Using the Toolbar, whenI select the file, there doesn't appear to be any change on screen/