[Bf-funboard] A needed node.

David Jeske davidj at gmail.com
Tue Jul 2 04:51:39 CEST 2013


@Knapp - I'm 100% on board with your goal of "easy to use random
factors".... What I'm unclear about is the most useful node to achieve
these results. Let's discuss some of the details to figure it out..

The trouble you are having, is that "object.random" effectively hard codes
the seed to "object.id", and only provides one random number per object. To
do your random colors, you want to generate three different random numbers
per object.

I believe when you request "a node that generates a simple random number"
you are really asking for "a node that generates a random number based on
object.id and that node's instance-id", such that when two such nodes are
created, they produce different random outputs for the same object.

In this case, the "object.id" and "node-instance-id" are the seeds to the
randomness, and there must be a stable seed, otherwise it won't even
produce a stable surface color at a single texel !

I think a more general version of this node, would be a (1d) "Noise Value"
node which takes a set of seed-input values (2-4?) and produces a
psudo-random output value based on these inputs. It might also use it's
node-instance-id, just to be easier to use. However, if it didn't, you
could easily simulate this by just manually changing an unconnected seed
value for each "Noise Value" node.

I'm not familiar with CUDA, so I'll sidestep GPU viability.. however, that
is certainly easy to do on the CPU.


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