remove or hide camera from dropdown menus

 

sometimes you have too many utility or test cameras and you want to remove them from your dropdown menus... To do this, add the "soho_renderview_menu" property to your camera's parameters and uncheck the box. Tip taken from Tomas/anim of Odforce

force multiple curves to have same Normal

If you have a bunch of curves and then polyextrude them, sometimes the normals will get funky and some will be facing the wrong way. A POLYPATH sop added before the extrude can usually fix the resulting normals - I think it kinda fuses the curves into one object, something like that.

delete faces but keep edges

 say you got a 10x10 grid and you just want the borders...

use a divide sop with "remove shared faces" right?

Yes, but... the shape will remain filled. So how do you get rid of that face, but keep the edges?

Use the "Ends" SOP. and set the closeU parameter to "Unroll with shared points"

Woop.

Camera frustum display toggle

 

Frustum display in Houdini

getting areas of pieces and removing them. Eg object is being divided somehow.

 

Say you want to blast the large lower shape to just get the caps, but this shape is evolving and moving (and therefore the parts you want to delete are changing in size & number/point count etc!)....

You gotta measure the area of each "connected" piece, then kill them based on a threshold. It's easy when you say that, but actually there's a bit of other stuff involved.

   

This is the rough setup.
So make a For Each block & set it to Primitives. Do a Measure - select Area. This only gives us the area per FACE. We want the whole piece's area. Sooo, we promote it to Detail level & use the SUM promotion method. ie - it adds all the area attribs on a piece together. 

Once this has been done I promote the attribute back to Point level (using average as the promotion method).

Outside of the loop we can write a little wrangle to delete the pieces based on area-

Just a simple removepoint expression. I use a float channel slider so that the value can be tuned for the animation. it might not be necessary for you.

Shoutout to Felix for helping out with the attribute promoting bits!