Creating a custom FME function with c++

a function must be evaluated?

I must write "@Evaluate(@CenterOfMass())" for that my function is executed.

That was somewhat a rhetorical remark...srry

afaik a function has to be evaluated Always..

I'd be surprised if you needed @Evaluate. After all, the transformer in that demo folder doesn't include it. Anyway, I've asked some folk at Safe to take a look. I've done a few searches but didn't find anything that would help me answer definitively.

Does this function return a number? I was thinking there's a difference between the text and arithmetic editors, but even then it should work without @Evaluate in a text editor as long as you don't include it in a mathematical formula in there. The only difference is it might be returned as a string, not a numeric attribute type, but we aren't great at handling data type inside a workspace yet, so the difference would be small.

Thanks for your review. You are right, the transformer in the demo folder doesn't include it, but it seems necessary to run in the AttributeCreator panel. Regardless of type of value returned. Other issue is how I define the syntax of my function to be recognized by FME.

Hi Alvaro,

I've filed an enhancement request to have these editor dialogs automatically recognize custom functions. It is PR#69429 and we'll wait and see what our developers say.

I don't have an answer for your other question, but I do wonder if you can create your new UUID function as a custom transformer instead of trying to code a solution. Or, if you can code it in Python, then you have two options: either embed it inside a custom transformer using a PythonCaller transformer, or use FME's @Python function to execute it.

If you're determined to code a solution then I'd suggest you join our Development Partner Program. That program includes technical support for this type of issue, and can even include the ability to send a developer to our Vancouver office to work with our staff directly. You can find more information on our web site.

I hope this information is of use,

Regards

Mark

Mark Ireland

Hi Mark, thank you very much for your support!!!!

To avoid these issues, I created finally a custom transformer similar to "CenterOfMass" sample. It works for me, but it is a pity not to insert the function in a more appropriate manner. I must concatenate a transformer for each attribute to assign in my workflow.

Really the code is a bit more complicated, I use a c++/cli dll running as a wrapper to call a c-sharp/.NET module with the specific code to run (It must run as fast as possible and the python already developed has poor performace). It works fine and I get 2x or 3x of performance improvement, I congratulate you for the SDK and your product!

Alvaro