For loop question

[Daniel Brassard]

Hello ICE Gurus,

I have this piece of ICE tree that need to repeat based on an integer value input. It repeat between the add node and the scalar to vector node, with each iteration feeding a value to an array. In code that would be easy:

Code: Select all

var u = 4;
var x = -.05;
for (i=1, i <= u-1, i++) {
x = x + 1/u ;
}

I must admit my brain is fried from the lack of sleep. How do you change the ICE tree to correspond to the for loop?

Thank you for your help!

[Hirazi Blue]

I'd look into the "Repeat" or the "Repeat with Counter" compound,
and the "While" or "While with Counter" compound,
The "with Counter" variants give access to the counter itself, obviously,
if you plan/need to use it in your tree...

But I'm no ICE Guru myself,
so there probably are better solutions...
;)

[Memag]

No guru here, but this might help.

User guides

Looping: While and Repeat
The While and Repeat nodes can be used to “loop” or repeat a branch of a tree.
If the Condition of a While node has been filtered out for a given member of a data set, then no processing is done for that element. Similarly, if the Iterations of a repeat node have been filtered out, no processing is done for that element.
If you need to get the iteration number within the loop, store it in a custom attribute.

Area thread

hello Ron,
just take a look into the “Constrain Strand Length” compound. Within this compound you can find another compound “Iterate over Strand Fixing Segment Lengths"->"Iterate on Array”. This is a good example how loops with an iterator can be realized within ICE.
Best regards,
chris

Check out these posts as well,

Repeat Loops And Redundant Attribute Declaration

Polygon Islands : Using Arrays


Hope some of it helps.

[xsisupport]

The alternative to a loop is to build an array of the values (in general, preferred over huge loops). Depends on the rest of your tree whether you could use this array.

[xsisupport]

For loop version

[Daniel Brassard]

Wow, that was quick. Thanks everyone for your replies.

I did look at the repeat, repeat with counter, while and while with counter, unfortunately all have an execute output port which is incompatible with the slice and keep polygons node which take an array as input.

It look like the array solution from xsisupport is the way to go.

Other solutions are worth noting (iterate on array, polygon islands: using arrays from Guillaume Laforge blog, etc). Thanks for the links, I will definitively investigate them all, these tricks are going to be useful in a near future.

On to the drawing board. Maybe a topology compound coming soon!

Cheers!

[Daniel Brassard]

Excellent! The array method work very well and allowed me to eliminate some nodes.

EDIT

I have uploaded two compounds in the ICE Compound area: DB_Cube_V1 and DB_Cube_V1a

Hope you like it!

Cheers!

Dan