params of DrawStringWrapped() ax, ay means ambiguous

[airylinus]

It's says:

The anchor point is x - w * ax, y - h * ay, where w, h is the size of the
// text. Use ax=0.5, ay=0.5 to center the text at the specified point.

I'm not sure how to understanding the "anchor point", Does it the very central point ( both center of horizon and vertical ) of text area( or whole image?) ? Or the left top point of text area as OpenCV?

I noticed ax, ay coordinate with Align setting, but still cannt get it.

[fogleman]

Did you try rendering with different values to understand how it works?