It can be very tricky to do. The easiest way would be to convert your instances into mesh. There are various ways to do that. ICE modeling or Momentum's instancer are possible ways but if your instance master have hierarchies, you probably will need to merge them so that it's only one object. The down side to this technique is that converting instances to meshes can make a very large mesh depending on the complexity of your scene.
There are other ways you can proceed but they all require some very advance and complex implementations. You can raycast on the instance masters by multiplying the ray origin and direction by the reverse of the particle matrix, but you'll need to figure out a way to select which particles to raycast on first as you don't necessarily want to test all of them. And if you have more then one instance master, you're going to have to separate each master in your ice tree or line them up so they don't intersect and decal the origin accordingly. It can become very complex very fast. Another idea is to use a tool like Creation Platform or Arnold to do the ray tracing for you and return the proper information through a custom ICE node or something, but that's another very complicated approach to implement. Hopefully something like Momentum's instancer will be good enough for you. If converting your instances to mesh is not feasible on your machine, then I'm afraid there's no easy solution. -Mathieu -----Original Message----- Subject: ICE: Raycast against instanced geo? From: "Tim Crowson" <[email protected]> To: [email protected] Date: 2013/10/01 15:41:01 SignatureIs it possible for ICE to recognize instanced geometry when using Raycasting? Either instanced explicitly by the user as in the case of a model, or via pointcloud replication? -- Tim Crowson Lead CG Artist Magnetic Dreams, Inc. 2525 Lebanon Pike, Building C. Nashville, TN 37214 Ph 615.885.6801 | Fax 615.889.4768 | www.magneticdreams.com [email protected] -------------------------- To unsubscribe: mail [email protected] with subject "unsubscribe" and reply to the confirmation email. -------------------------- To unsubscribe: mail [email protected] with subject "unsubscribe" and reply to the confirmation email.
