The Romans were masters in the art of murals, frescos. They were able to create the illusion of shape and space on a two dimensional surface. They often depicted landscapes or human figures. These were not flatly 'colored by number' in Greek style but showed elaborate shadows and highlights. The Romans were well aware of the influence of light on a color.
Fresco detail from the Villa of the Mysteries at Pompeii

Where the Greeks used one single color for skin, the Romans went to great lenghts to create an illusion of form and space. However, the illusions that were thus created, brought along some interesting paradoxes. Up till this very day there's a statue of emporer August in Rome.
The emporer carries a metal cuirass, as usual in those days. While the statue is now completely white, research shows that originally it was completely painted. The metal cuirass was richly decorated with reliefs of war images. One would expect the cuirass to have been painted with some color to represent metal, including the reliefs. However, a recontruction of the original colors has shown that the reliefs ware painted in 'realistic' colors. But because the reliefs were metal, they should have been metal 'color'. It begs the question what is more 'real' in this case: the metal of the cuirass or the colors of images depicted in the reliefs.