Sean-R

You don't need to use a foreach. Look into wedging: http://www.sidefx.com/docs/houdini/nodes/out/wedge.html

To put the vertices in an array attribute: i[]@prim_vertices = primvertices(0, @primnum); You have to declare @prim _vertices as an array. You don't need the first line of your code, that would declare a variable. Unless that's what you want of course

The file merge SOP should do the job: http://www.sidefx.com/docs/houdini/nodes/sop/filemerge.html

That should work, @NewVec should be visible in the geometry spreadsheet. To get it to write as a vector attribute you will need to put a v before the @.

The Entagma guys have a nice solution for this:

The code in a wrangle is applied to each prim/point/whatever at the same time. In your code your say that only primitives with a primitive number of 0 and 4 can be white which isn't possible as it can only have one @primnum assigned, try replacing "&&" with "||". You will also need to initialise the @Cd attribute before the if statement, this should work: @Cd = 0; if(@primnum == 0 || @primnum == 4){ @Cd = 1; } If that's all that you are doing in the ForLoop, then I don't think you need it

Hey! So I think I get what you mean. I used the @vrtList that you created to get the first and second vertices of each prim, blended the positions to get the midpoint and then created a point at that halfway position. I've attached an updated version of your scene with the following code: i[]@vrtList = primvertices(0,@primnum); int vp1 = vertexpoint(0, @vrtList[0]); int vp2 = vertexpoint(0, @vrtList[1]); vector midpoint = lerp(point(0, "P", vp1), point(0, "P", vp2), 0.5); addpoint(0, midpoint); If you're using this as a pivot for the primitive you don't need to create a point, just bind the lerp expression to an attribute to reference in the primitive SOP. To see the vertex numbers in the viewport, hit D to bring up the Display settings and select Numbers from the Vertex checkbox list. I'm not sure why you need the Foreach network, especially set to Count. What are you trying to achieve? halbetweenpoint_b_v2.hipnc

You shouldn't need to create a point, this code will create a pivot attribute in the place that you want it: //Get all points in a primitive and put into an array int foo[] = primpoints(0, @primnum); //Get the average position of the first and second point in the foo array v@pvt = lerp(point(0, "P", foo[0]), point(0, "P", foo[1]), 0.5); In a Primitive Sop you can call the @pvt attribute using the prim expression. The expression in the pivot would look like this: prim(0, @primnum, "pvt", 0) You will need to change the last value to match with each parameter. So x = 0, y = 1 and z = 2. This probably wont rotate the primitives how you want though, check out this section of Matt Estela's website: http://www.tokeru.com/cgwiki/index.php?title=HoudiniVex#Rotate_prims_around_an_edge I can't check your file at the moment as I'm at work but I can look at it tonight

You could use the particles age and life attributes and write them into a scale attribute in a wrangle like so: // Normalize the age by dividing it with the life attribute, this will give a value between zero and one float nage = @age/@life; //Because nage is a float variable it will be copied three times in the vector scale attribute v@scale = nage; Then plug this into a copy sop with your line geo at the maximum length you want.

Yes! I've fixed the code

This should work: // Get distance of primitive to point position of second input, Sphere is plugged in to second input // float dist = distance(@P, point(1, "P", 0)); // Get radius of sphere, I made a relative reference to the spheres scale in the radius parameter that is created // float rad = chf("radius"); // If the primitive is inside the sphere, delete// if(dist<=rad){ removeprim(0, @primnum, 1); }

Do you mean the playback is too fast? There's a clock icon on the timeline bar which needs to be enabled to play back in realtime. Otherwise, if you need to slow the sim down you can use a timewarp node,

FIrst of create a random number between 0-1, you can use the @ptnum or @id (if you have one) attribute, you can then reference this random number in a ramp expression. The code would look like this: float rand = rand(@ptnum); v@scale = chramp("Scale", rand); You can then hit the spare parameter toggle next to the vex expression and adjust the ramp curve to how you want it. Bear in mind this will distribute the scale of the debris to between 0-1 so if you want them to be a different scale to this you would need to fit the scale value after the ramp expression.

Check out this video by Matt Ebb. He has something similar to what you're after halfway through (but it's definitely worth watching the whole thing)

Is it a Packed Primitive? You could use a point expression on the camera transforms at object level