When drawing shapes with an attached text the default behaviour is that the text size is relative to the shape size.
It may be desired that the text has a fixed worldspace size independent from the scale of the drawn shape.
This can be achieved with this global setting that forces all text at drawn shapes to a fixed worldspace size.
The default value of 0 means "constant worldspace text size is disabled".
The value defines the width of one text letter in worldspace units.
This setting competes with the forcedConstantScreenspaceTextSize_relToScreenHeight_forTextAtShapes setting.
If both settings are activated (that means set to something else than 0) then "forcedConstantScreenspaceTextSize_relToScreenHeight_forTextAtShapes" wins and "forcedConstantWorldspaceTextSize_forTextAtShapes" is ignored.