time shifting copy stamps

Needed to time offset an alembic which was being copy-to-points.
The methodology is the same as a previously posted thing, but the copy-to-points node needs to be situated inside the For Each loop



if you squint, you'll see there's an attribrandomize node. I've made an integer attribute called TimeOffset and ..randomised it..
In the timeshift node, I make a spare input and point it to ../PT, which holds said TimeOffset values

The value for the timeshift is : $FF+point(-1, 0, "timeOffset", 0)

so, we take the current frame and add the individual time offset value to it.

Shweet.

cryptomatte AOV with arnold/HTOA

Another simple thing, which I always forget.

The most common crypto attribute I use is crypto_asset.
It seems to work best assigned at primitive level. So - in a primitive wrangle for example -

s@crypto_asset="poop"+itoa(@primnum);


The next part is to create an Arnold Shader Network, call it something like "CRYPTO"
Inside this, make an AOV Output  node. Create a cryptomatte node and hook this up to the aov_shader input. You may need to create a user_data_string with "crypto_asset" and plug that into the "crypto_asset" input of the cryptomatte node.


The last bit, is in the Arnold ROP you're using. In the AOV section, where it says "AOV Shaders", point it to they CRYPTO shop you made earlier -  /shop/CRYPTO

then add a new AOV and select "crypto_asset" from the list.

Hopefully this works!

Crypto_object is used when things are in different Houdini Objects... it isn't something that I usually do though..

distort undistort stmap

This stuff is so boring.

original source 4448x3096
plug into undistortion node to get undistorted res 4560 x 3174 - ST MAP will be this res

plug 4560x3174 into redistort node to get 4448x3096 - ST MAP will be this res