A variable-color region (106) of an information-presentation structure extends to an exposed surface (102) at a surface zone (112) and normally appears along it as a principal color. An impact-dependent portion (138) of the variable-color region responds to an object (104) impacting the zone at an object-contact area (116) by providing an impact signal if the impact meets threshold impact criteria. The impact signal identifies an expected location of a print area (118) in the zone and supplemental impact information for the impact. Responsive to the impact signal, a controller (702) determines whether the supplemental impact information meets supplemental impact criteria and, if so, provides an initiation signal. The impact-dependent portion responds to the initiation signal, if provided, by temporarily appearing along the print area as changed color materially different from the principal color. The print area closely matches the object-contact area in size, shape, and location.
