In the lower right corner of windows that display graphics plots and diagrams for treatment planning purposes you will find a button labeled Auto and a small slider that controls font size. This feature was introduced at version 6.7.7.
When Auto is enabled, Plaque Simulator will automatically rescale text font and graphics line width as a function of window size and zoom (magnification) to maintain a roughly proportional appearance as window size changes. This works well for large and/or high resolution video screens such as what Apple refers to as "retina" displays and when doing high resolution screen captures of greatly enlarged windows for publication purposes. By default, Plaque Simulator launches with automatic scaling enabled.
When Auto is disabled, graphics line width will generally default to 1.0 graphics units (e.g. points or pixels) and you can manually adjust the font size of most labels using the adjoining slider and the font size of other graphics elements (e.g. rulers and point of interest labels) by customizing the individual property settings for those elements.