Sopsolver-timestep

[msunar20]

hi I was trying to use Sopsolver expression to output the previous timestep, but i am not getting the result. this is the expression i use inside sopnetwork using object merge node.

stamps("../OUT", "DATAPATH", "../../.:agents/Geometry")

flocking_system.hipnc

[MENOZ]

if you go inside the sopsolver there are already some object merge with expressions setup for you to import the data, But it would be interesting to know how does the samps works if you are using an external sop network.

The syntax of the stamp expression inside the object merge you are using certainly needs the ` ` quotes around it or it won't solve.

If you put down a sop solver now it has only one input, because is version 2, you can see it by middle clicking on the node, if you put down a solver node in SOP, inside the sop solver it is still a version 1. This is why you have the error in the solver which says "connection to input 0 is the wrong type".  I would like to know what is the difference between sopsolver 1 and 2.

I would put down a multisolver and connect the object to first input and the solver to the second. it probably works if you use an apply data instead, but i'm not sure.

 

from help

By using an expression like stamps("../OUT", "DATAPATH", "../.:objname/Geometry") in an Object Merge SOP, the output of the previous timestep can be used as the starting point for the next timestep within the SOP Network.

so you can use "../OUT" in the stamps to point to a SOP NODE inside the solver? i am lost. i tought you could only stamp from the sop solver itself, which allows you to stamp the global parameters.

[msunar20]

Hi Andrea,

I understood the differennce between version 1 and version 2 sopsolver.

But since i am new to houdini. I am really struggling to understand the syntax issues. 

Here is my file once again. Could you please help me to setup the node according to your description.

 

flocking_system.hipnc

[MENOZ]

i had some time now and tried to make it work, hope this helps

in dop you have 3 approaces, one with geometry vop and noise if that's all you want to do it might be better that passing in a sop solver.

a sop solver with gemetry manipulation inside himself with defaults object merges

and a sop solver pointing to a sopnetwork. in here there is a switch to test different paths you can put in the stamps expression. all of them works at least in this case, but I don't undestand WHY. if anyone could halp and make some clarification on how the stamps works would be amazing. cheers

 

 

flocking_system (1).hipnc

[msunar20]

thank you very much for all your effort man. I really appreciate it. I feel really great how people are willing to help student like me. 

Btw, you are an FX artist. right? how long do you have been in this industry? Would you liek to give me any direction, since i have 6 month for graduation and hopefully i am trying get enough knowledge as possible once i am out of school.

 

[Anton81]

To the both of you, thank you soooo much!!! Trying to figure this out while following the tutorial has been driving me insane for the past two days.