For topology, there is no SDK access. But a custom node can do all the low level stuff (manipulating the so called PolygonalDescription). Same for Kinematics, a custom node can manipulate a 4X4 matrix. At the end you need to set the topo/kine using the corresponding attribute.
Here is an example (with source code) to create topology using a custom ICE node: http://frenchdog.wordpress.com/2012/01/05/happy-2012/ If you want to do everything with one node, it is a job for a custom operator I think. Guillaume On Wed, May 15, 2013 at 6:07 AM, Ahmidou Lyazidi <[email protected]>wrote: > From my small experience about this, you can't make a custom topology or > kinematics "node", you make a node that abstract the more or less complex > computation, then you feed the topology nodes (or a matrix in the case of > kinematics). > As you stated you can't use locators, or location queries in a custom ice > node, so if you need them the workflow is to break you ice node in smaller > parts. > > About the preformance sometimes it's faster, sometimes quite the same. I > made a parallel transport frame node, the gain was only 15% but the setup > faster. > This node seems to perform way faster: > > http://shaderop.com/2011/07/cubic-bezier-curve-node-for-softimage-ice/index.html > > A > > > ----------------------------------------------- > Ahmidou Lyazidi > Director | TD | CG artist > http://vimeo.com/ahmidou/videos > > > 2013/5/15 Matt Lind <[email protected]> > >> well, let's answer the questions first: >> >> 1) Does anybody have source code they are willing to share for custom ICE >> Nodes that deal with topology and/or geometry? >> >> 2) Does the lack of reference, location, and execute ports for custom ICE >> nodes mean I cannot cast a location search from inside an ICE node? >> >> >> >> To answer your question: >> >> Imagine two nulls and two NURBS Surfaces. the task is to find the >> nearest location from the first null to the first surface. At that >> location, build an orthonormal basis and compute the local transform of the >> null relative to that basis. Then reconstruct that relationship by >> applying it to the 2nd null relative to the 2nd surface assuming both >> surfaces use uniform parameterization, not non-uniform as is the softimage >> default. Version 2: extend to operate on vertices of polygon meshes >> instead of nulls. I have a working version, but it is slow and not very >> stable. >> >> The problem I'm encountering is it simply takes too many factory nodes to >> be able to work efficiently. Each node has a certain amount of overhead >> regardless of what it does. Plus, the support for NURBS in ICE is rather >> abysmal. I have to construct my own orthonormal basis plus implement my own >> algorithm to convert from non-uniform parameterization to uniform >> parameterization. Both are doable, but take very many nodes to do it >> (including support for edge cases) making the whole effort rather clumsy at >> best. The parameterization conversion is expensive as it involves sorting >> and searching (while/repeat/counter nodes). When applying the ICE Compound >> to a polygon mesh with 5,000+ vertices.....it gets the job done, but >> chugs. >> >> I have a version of this tool written as a scripted operator, and it >> performs really well because it has better SDK support and the >> sorting/searching can be better optimized. But one shortcoming of scripted >> operators is they self-delete if an input goes missing (which often happens >> on scene load or model import when the content has been modifed >> externally). This in turn causes content using the operator to malfunction >> generating bug reports which are sent to artists to fix. Unfortunately >> most artists weren't around when the content was created years ago, so they >> have no idea what's wrong, what the expected output is supposed to look >> like, or how to fix it. Often an asset has to be retired and replaced. >> This is my motivation for rewriting the tool as a custom ICE node as ICE is >> much more graceful when it's inputs don't exist - it just turns red and >> sits patiently until conditions improve. This gives artists a chance to >> fix the problem without having to sweat the details because they can read >> the GetData node to see what's missing, then find and repair it. I'm >> trying to make the content in our pipeline more durable. >> >> So...I'm looking for code samples of how to deal with topology and >> geometry in ICE. So far I have not found any. >> >> >> Matt >> >> >> >> >> >> >> ------------------------------ >> *From:* [email protected] [ >> [email protected]] On Behalf Of Raffaele Fragapane >> [[email protected]] >> *Sent:* Tuesday, May 14, 2013 9:00 PM >> *To:* [email protected] >> *Subject:* Re: custom ICENode - questions and request for example source >> code >> >> Yeah, same hunch here. >> Unless the performance expectations are in the multiple characters >> real-time concurrently, in which case I think neither way is gonna get >> there usually. >> >> >> On Wed, May 15, 2013 at 1:04 PM, Ciaran Moloney <[email protected] >> > wrote: >> >>> I'm sorta , kinda sure that's a dead end for a custom node. You might be >>> better off optimizing your ICE tree. It doesn't sound like such a complex >>> problem, care to share? >>> >>> >>> On Wed, May 15, 2013 at 2:41 AM, Matt Lind <[email protected]>wrote: >>> >>>> I’ve been looking at the ICE SDK as a start to the process of writing >>>> custom ICE Nodes in C++. I need to write topology generators, modifiers >>>> and deformation nodes. So far all the source code I’ve seen supplied with >>>> Softimage only deal with particle clouds or primitive data such as >>>> converting integers to scalars. Does anybody have source code for working >>>> with the Softimage SDK inside an ICE Node to modify >>>> topology/geometry?.....or Kinematics? Example: creating a polygon mesh >>>> from scratch, adding/removing subcomponents, dealing with clusters, etc… I >>>> ask this partly because the ICE SDK docs say to not use the object >>>> model….which leads to the question – how do I do anything?**** >>>> >>>> **** >>>> >>>> **** >>>> >>>> **** >>>> >>>> **** >>>> >>>> While also browsing the SDK docs, I saw in the ‘limitations’ section >>>> that custom ICE Nodes cannot define reference, location, or execute >>>> ports. Since I am very interested in working with locations, does this >>>> mean I cannot do queries for locations from inside the ICE Node? Or does >>>> it only mean I cannot send/receive locations from other ICE nodes?**** >>>> >>>> **** >>>> >>>> Example:**** >>>> >>>> **** >>>> >>>> I need to write an ICE Node which takes a polygon mesh and 2 NURBS >>>> Surfaces as inputs, and whose output is the deformation of a 2ndpolygon >>>> mesh. To accomplish this feat requires the use of point Locators >>>> to map the relationship between the first polygon mesh’s points relative to >>>> the first surface, then re-interpret that information to deform the points >>>> of the 2nd polygon mesh in relation to the 2nd surface. You can >>>> assume the two polygon meshes and two surfaces have identical topology. I >>>> need to write this as a custom ICE node because it is prohibitively >>>> expensive to use the factory nodes (too many nodes/workarounds required >>>> leading to severe performance degradation).**** >>>> >>>> **** >>>> >>>> I’d like to be able to do a point locator query from inside the custom >>>> ICE node for performance (and convenience) reasons. Sample code would be a >>>> big help.**** >>>> >>>> **** >>>> >>>> **** >>>> >>>> Anybody?**** >>>> >>>> **** >>>> >>>> **** >>>> >>>> Matt**** >>>> >>>> **** >>>> >>>> **** >>>> >>> >>> >> >> >> -- >> Our users will know fear and cower before our software! Ship it! Ship it >> and let them flee like the dogs they are! >> > >
