Following up on my previous post about understanding context, here’s another [entry-level] video about context, this time looking at how “per-point context” is specific to an object.

http://vimeo.com/26639288

Inspired by this xsibase thread.

Modulo by 19:

lobbecke on xsibase:

Chris_TC on xsibase: Keep in mind that the result very much depends on the vertex index order of your object

This video looks at using the FCurve node, together with the Rescale node.
Hat tip to everybody on the ICE: Fcurve use XSI list thread.
http://vimeo.com/26281613

After I finished the video, I realized I should have built a compound more like this:

A poster on xsibase asks “how can a build an array of booleans where the pattern 0101 is repeated 256 times?”

Here’s how:

Note: This is with Softimage 2012.

The Reserve Array node reserves memory for an array, but it doesn’t construct the array for you.

So, for example, if you try to use Set in Array you may find that it doesn’t work, because the array element you’re trying to set doesn’t exist yet. In this tree, Reserve Array gives me an array with one element. So trying to set the second element has no effect.

I’d have to use Push on Array here to get the desired result:

Or I could make sure the array elements exist like this:

I could also Resize the array after I reserve it.

If you’re starting starting to work with ICE, you need to understand the concept of context.
http://vimeo.com/26272061

In this case, the customer reported that the Filter node didn’t seem to work consistently. In the scene I examined, it seemed to be a problem with the construction stack: for some reason, the ICE tree operator wasn’t being pulled (evaluated). Here’s a quick walkthrough of the investigation 😉

http://vimeo.com/25620343

I looked a little deeper into this case, using GetConnectionStackInfo, and I found that somehow the ICETree operator was below the cluster ops:

// INFO : Objects that read from the primitive:
// matchstick.polymsh.secondaryshapemarker
// matchstick.polymsh.animationmarker
// matchstick.polymsh.shapemarker
// matchstick.polymsh.modelingmarker
// matchstick.polymsh.cls.pnt.clslist.Point.AddToClsOp
// matchstick.polymsh.cls.pnt.default_Point.SetClsFromICEOp
// matchstick.polymsh.Init_ICETree

If I created another ICETree op and moved it below (after) the original ICETree op, then the ICETree operator would have access to the cluster:

ApplyOp("ICETree", "matchstick.polymsh", siNode, null, null, 0);
MoveOperatorAfter("matchstick.polymsh", "matchstick.polymsh.Init_ICETree", "matchstick.polymsh.ICETree");
DeleteObj("matchstick.polymsh.ICETree");

// INFO : Objects that read from the Sphere primitive:
// matchstick.polymsh.secondaryshapemarker
// matchstick.polymsh.animationmarker
// matchstick.polymsh.shapemarker
// matchstick.polymsh.modelingmarker
// matchstick.polymsh.Init_ICETree
// matchstick.polymsh.cls.pnt.clslist.Point.AddToClsOp
// matchstick.polymsh.cls.pnt.default_Point.SetClsFromICEOp