Here’s another way to split an edge into N new edges of equal length. This time, I use the offset.
With a split ratio of 1, I get a bunch of new, zero-length edges that all pile up at the far vertex.
But I can use the offset to move all those edge vertices down the vector between the two original edge vertices:
Word cloud for strings xsi.exe | find /i “cannot”.
A few messages that caught my eye:
Sometimes it’s interesting to look back at how you wired things together on the first go. For example, look at that weird Pop from Array bit on top; I kinda like it, but maybe doing two explicit Select in Arrays is more understandable.
Anyways, here’s something that could be useful when splitting edges…
Here’s the basic idea of how to split an edge into N equal-length new edges. Notice how I work backwards (in the sense that my split ratio decreases). That way I don’t know have to know (or care) about the new edges. I just keep splitting the same edge, whose EdgeIndex I already know.
Based on that observation, here’s a rough draft of an ICE tree that takes an edge of length N, and splits it into N equal-length edges.
Making of IGA Petits bouffeurs
by Shed
Finding indices of negative values in an array
by iamVFX
Test if a point is inside, on the surface or outside
by Daniel Brassard
Filter one array by another
by kykeon
hexagon cylinder
by msktkhs
hexa
by msktkhs
Animated sine wave
by Ola Madsen
si = Application #sdef = si.GetShaderDef( "Softimage.BA_particle_density3.1.0" ) sdefs = si.ShaderDefinitions print sdefs.Count # 1390 for sdef in si.ShaderDefinitions: print sdef for n,v in map( None, sdef.Attributes.Names,sdef.Attributes.Values ): print " %s=%s" % (n,v)
For most shaderdefs, the only attributes are “shaderlocation” and “thumbnail”.
Softimage.BA_particle_density is one of the few that has anything more interesting. If a Softimage.BA_particle_density shader exists in the scene, you’ll get this:
# Softimage.BA_particle_density3.1.0
# shaderlocation=3
# thumbnail=particle.bmp
# {C535FA4D-E44A-45EB-AEE0-9F9AAEA91745}=None
# {20ECB4F8-A4A1-44FE-956A-0F6E98D541A8}=Color,Id,PointVelocity,Orientation,Size,PointPosition,Age,AgeLimit,StrandPosition,StrandVelocity,StrandSize,StrandOrientation,StrandColor
If you look at the BA_particle_density3 spdl, you’ll see that that last attribute corresponds to the “ICEattribute” entry for the output parameter. That ICEattribute tells Softimage to pull date from the ICE tree during rendering.
SPDL
Version = "2.0.0.0";
Reference = "{047CA80F-9EED-4507-9F83-4BB77C01DFC1}";
PropertySet "BA_particle_density3_params"
{
Parameter "out" output
{
title = "BA_particle_density3 output parameter";
guid = "{0B955B1D-CCBA-4B68-9CD3-ABE9467D665D}";
ICEattribute = "Color,Id,PointVelocity,Orientation,Size,PointPosition,Age,AgeLimit,StrandPosition,StrandVelocity,StrandSize,StrandOrientation,StrandColor";
SOFTIMAGE|3D version 3.8 CD cover from 1998 (picture courtesy of Alexei Godek; polaroidization by me)
Suppose you want to use an ICE attribute to drive some behavior in the render tree. For example, you may want to introduce some randomization to a procedural texture. Here’s one way to go about it.
First, create an ICE attribute on each object. You’ll use this object as the seed for the Random Value node (you need a different seed for each object, otherwise you’ll get the same “random” number for each object).
si = Application
i = 0
for o in si.Selection:
a = o.ActivePrimitive.Geometry.AddICEAttribute("_seed1", 2, 1, 1 )
a.DataArray = [ (i) ]
i = i + 1
Now apply a simple ICE compound to each object.
Seed and random scalar value for each object
From the top reasons to buy brochure (PDF).
Hmm, Softimage is mentioned just about as much as the other products.
If I remove product names and some other words, to leave only the other reasons, I get this:
Let’s say you wanted to delete certain points for some reason; maybe they were misbehaving or something. You could just stick the IDs into an array and feed that into Find in Array, like so:
This is an answer to a question on si-community, which timed out on me when I clicked Submit. So now it’s my post for today. After struggling with Maya nParticles for an hour, I can’t think hard anymore.
eX-SI 