Simple project to learn Houdini

[EdArt]

I'm new to this place, so apologies if I'm being dumb about anything.

The project is to fire a beam at a piece of geometry, and have it fracture at the point of impact, like a simple sci fi gunshot. I have a rough idea of how to do the destruction, but which nodes should I use to cast the ray, and then find the intersection? Also how do you even define a direction or a vector to start off with? Currently I'm using a very long single-span curve, but I'd like to find a way to cast the ray infinitely.

Any help is much appreciated. Thanks very much. 

Edited November 9, 2017 by EdArt

[animatrix]

You can do all this inside a single AttribWrangle using the intersect() function.

[Jesper Rahlff]

you could take your position of origin (where you want to cast your ray from), and subtract that from your target position in an attributevop and then use a bind export node to export your newly crafted vector as an attribute. (lets for the sake of this example call that attribute myattrib).

you then have quite a few options on how to get your origin point to the position of the intersection position.

the most straight forward to understand I believe is using the Ray node. The Ray node takes points to ray and some collision geo to ray onto. you can then specify how is should find a direction to cast the ray, and because we created a vector named myattrib (which holds the distance and direction to your collision geo) I would suggest that you use that.

if you wanna go the attribute wrangle way this would be a good place to start: because we have crafted a vector which we exported you can in an attribute wrangle do the following: v@P += @myattrib;

 

hope this helps.