Component panel: how to use macros for component formulas

[adam82]

Hello everyone.

 

I'm a bit confused  about how the "components" tab works in CA at the Specification panels, and I can't find a clear description of it either on the forum or in the CA Help. Could someone help me understand it?

 

My problem and my desired outcome is the following: 

I have to design a French drain system around a slab. I want to put into the material list the pipes, the gravel around the pipes and the geotextile fabric around the gravel. The slab is quite big and has a complex shape, so I wanted to rely on the material list calculation rather then recalculation it by hand each time the plan is modified. 

 

My idea was to use a polyline solid () for representing the gravel, and use its surface to represent the geotextile fabric.  The quantity of gravel should be calculated based on the volume, and the area of the geotextile should be calculated based on the surface area of the cube. Maybe this is not the right approach, but I couldn't find a better solution. 

 

When I assign the gravel material to the cube, I automatically get a component that is calculated based on the volume.

 

 

 

However, if I add another component to symbolize the geotextile, I can't use any macros for its surface area.

I tried using "= automatic_count" but it always returns 1. If I create a macro in the CAD -> Text -> Text Macro Management window, it always throws an "Evaluation error" message.

 

 

What determines the value returned by "= automatic_count"? And why can't I use it in a second component?

 

Thank you very much ! 

 

[robdyck]

When adding the component for your fabric, you'll need to do the following: go to Count / Formula, select Insert Macro. Select Object Specific / Area. Then beside that, select Apply Formula to Source Object.

[Chopsaw]

On 6/25/2023 at 12:38 PM, adam82 said:

The quantity of gravel should be calculated based on the volume, and the area of the geotextile should be calculated based on the surface area of the cube. Maybe this is not the right approach, but I couldn't find a better solution.

 

You are using the right approach and Robert has kindly provided the procedure to apply it.  The problem being that X12 does not provide the surface area as a macro.  This was not available until X14.  For a perfect cube try   area * 6  or for an irregular cube  area * 2 + perimeter * thickness

 

[adam82]

Thank you very much all your grate answers, that helped a lot, now it works !