PutUserData in custom operator

["Mathieu Leclaire" <mleclair(at)hybride.com>]

Hi, I’m creating a custom operator and I need to initialize and save data for each vertex of a polymesh. Since I have different kind of data to save in the _init call of the operator and reload at each _update call, I figured I’d create a class and put all my data in it then store that object using the PutUserData() function of the UpdateContext. But since I allocate memory in the constructor and delete that memory in the destructor, I think once I pull back my data in the _update function using GetUserData(), it returns me random data since it looks like the memory has already been released. Here is an example of what I’m doing:

 

#ifndef _myVertexInfo_h

#define _myVertexInfo_h

 

class myVertexInfo {

 

private:    

  int _nbPts;

  float* _targetPositions;

  int* _idxPts;

 

public:

  myVertexInfo (int nbPts) {

            _nbPts = nbPts;

            _targetPositions = new float[nbPts*3];

            _idxPts = new int[nbPts*3];

  }

 

 

  virtual ~myVertexInfo (){

            delete [] _targetPositions;

            delete [] _idxPts;

  }

 

  int GetNbPts() {

              return _nbPts;

  }

 

…

};

 

#endif

 

 

Then in my operator’s _Init function I do something like this:

 

…

//put local positions in obj2PtsPosArray.

obj2PtsPosArray = inGeom.GetPoints().GetPositionArray();

int nb = obj2PtsPosArray.GetCount();

  myVertexInfo * posData = new myVertexInfo (nb);          

…

ctx.PutUserData( (CValue::siPtrType)posData );

 

Then pull it back in the _update function doing something like this:

 

CValue::siPtrType pUserData = ctx.GetUserData();

myVertexInfo * posData = (myVertexInfo *)pUserData;

Application app;

app.LogMessage( CValue((float)posData->GetNbPts()).GetAsText());        

 

 

But I lose all information saved from the _init call. So what am I doing wrong? How do I allocate memory only in the _init function and release it only in the _term function?

 

 

 

I also have a second question: How can I store this information so that when I load a model containing instances of that operator, it won’t recalculate all that information from the _init call but load the data calculated when the operator was first applied. See, I only need to calculate the necessary information when it’s first applied, then use the calculated information at every _update call of the operator. But if I export a model containing instances of this operator, when I re-import it (usually by switching the low resolution reference model by a higher resolution one that contains this operator) then it recalls the _init of the operator and recalculates all the values instead of reusing the values that where calculated when first applied. I had the same problem with a previous operator I created but I overcame the issue by adding a “FirstLoad” Boolean parameter to the SPDL so that when it first got applied, it would change that parameter value to false and save the desired data in the rest of the parameters and so when it loaded again in a model, and the “FirstLoad” parameter value was set to false, it would only read the parameters instead of recalculating them. That worked well in that case because I only had a couple floats and a couple integers that had to be saved per operator so I saved them as parameters. Now I have whole arrays of data to save and it’s length is dependant on the number of vertices. How should I solve this issue? The only solution I have in mind would be to save it to a file but then we’d have files to manage with the model and paths to check… I’m looking for a way to save that data directly into the operator or somewhere in the exported model so that I can reload it when imported. Any suggestions?

 

 

Thanks for any help you can provide and sorry for the lengthy post, I just figure I’d better give too much information then not enough.

 

 

Mathieu Leclaire

R&D Programmer

Hybride