Saving areas of a field of objects

[revelationsr]

Hi there.

Honestly I have no real idea how to go about this problem. Often when at the very least has an good idea how to solve the problem, but is missing the last few steps, you can describe to the ideal solution in terms of what you alreay know about the solution. Make sence?

Ok here we go.

I have a huge field of plants. With packed primitives Houdini handles this shockingly well. They are all blowing in the wind. Interacting with various things that are happening in the field. All good. The problem is that we need to render this in Maya. No Houdini on the farm. So we exported this through Alembic to Maya. The Maya guy has wrote a thing that will convert this to a arnold proxy. The prosess is almost 100% automated. Works rather well. Here is where the problem comes in.

The machines on the farm does not have enough memory to render this. So I broke up the field into 5 chuncks. Still not enough. So here is what I would like. I want to be able to place a grid in my scene in Houdini that covers the field of plants. I would like to automate every plant that appears in one of the grid squares to save as their own alembic. So ideally if I need to change the size of the grid later down the line to match the farm memory. It will be just the case of one slider change and go get some coffee.

Or atleast this is a way I would imagine a solution. How ever this may be a very silly way to go about this.

So please. if you have any ideas how to go about this problem. Please let me know.

Thank you.

 

 

[3dome]

if all your plants are represented as one point (since its packed as far as i understood) you can put down a grid, fuse-unique the points, extrude the faces so you get boxes, ...ah it's easier if i just set up a quick file i guess

dm_outputSectors.hip

[revelationsr]

O yes this looks like it might do it. Thank you. I am going to play with this a little just to make sure I understand what is going on.

 

Thanx again

[revelationsr]

There is a issue with this setup. Since I need to export animation to the Alembic this does not seem to work.

If the write node is inside the for loop it will write out for each iteration. For each grid. So far so good. But on the next frame it will once again write out for each grid overiding the file from the previous frame. I tried getting around this by adding "$F" to the output. Which works by write out each frame for each grid. But then I have issues loading that into Maya. So ideally I will need one file for each grid with the entire sequance.

Any thoughts?

 

[3dome]

keep the grouping, but remove the caching. after the loop use a blast to only keep 1 group at a time and use wedging to render out each group with full frame range

[vtrvtr]

Very similar to 3dome, but still

 

 

slip_alembic_odf.hip

[revelationsr]

Wow that works do well. Thank you very much!