Hi All,

I’m having mixed results with using the current frame and time expressions to drive things in non-simulated ICE Trees. 

Test 1:  Point cloud with ICE tree, current frame node piped into Y point position driving an Add Point node.  Frame 1 moves the point to Y = 1, then no more movement as the time slider changes.

Test 2: A null with an expression, Fc, driving rotation Y.
Point cloud with ICE tree, get data ( null’s rotation Y) node piped into Y point position driving an Add Point node.  Y point position continues to change as the time slider changes.

Test 3:  A more complicated scene: neither scenario seems to have an effect in a non-simulated ICE tree.

So what’s going on?  Are we allowed to reference the current time value in a non-simulated ICE tree?  I would think it should work similar to an expression, where you can grab values at other times… right?

By default, the Current Frame node returns the local frame, i.e., the current frame relative to the beginning of the simulation. In your case, there is no simulation so that’s why it isn’t working. To fix it, open up the Current Frame node’s property editor and turn on the Global Time option.

I just found that the “Current Time” node does indeed update correctly, while current frame only works when another time based thing is connected to the same ICE tree.  Also, with both nodes, checking global time had no effect; current time always works, while current frame never worked by itself.

Attached is a file which demonstrates the inconsistency (bug?) with the current frame node in unsimulated ICE trees. Play through the timeline then try connecting and unconnecting the different “Add Point” nodes there.

Edit:
Found this in the help:

“There can be a difference between the local and global time only with simulated ICE trees.”

So that shouldn’t change the behavior of non-simulated ICE trees.

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I reported this to Soft several weeks ago. What I discovered was that you can actually get Current Frame to work, depending on what it is plugged into and if there is also a Current Time in the tree, but Current Frame fails most of the time and has some serious issues. Why it works sometimes, and other times not, using global time or not, is not clear. Current Time works and is very reliable.

You can create your own Current Frame compound using Current Time and some simple math, so it’s no big deal. Basically multiply Current Time by Get Data{Application.PlayControl.Rate}. For added precision you might want to round PlayControl.Rate if your using drop-frame rates. This will make sure the current frame output aligns to actual timeline frames.

Joey