When I read the 'backgroundColor' of a diagramObject, it comes back as '-1', which means 'default color' for this element type, as defined by it's MDG. Which is my case is Archimate, and as the element is a ApplicationComponent, it's pale blue in my diagram. All good, exactly as in the documentation.
Now I change the color to a different one, but I'm not totally stupid, and I remember what the original color was : '-1'.
Later, I want to change the back to what is was originally: so I set the backgroundColor to -1, and....it goes white. Not the 'default color'.
The database confirms this: BCol=13882323, which is white. Same is true for the border and font colors - all set to white.
But I have a plan - set these colors to 'nothing' via the API. Doesn't work - that just makes them black.
But I get out my big stick, and edit those the entries in t_DiagramObject.ObjectStyle, and delete BCol=.. then all is well. Back to having the default color.
Anyone else seen this feature? Or did I miss something ?
Another hour of my life I'd like to claim back from Sparx.