It is taken for granted that medical technologies will advance apace in the future, permitting rapid healing and perhaps even shaping of the human body. This submission is to provide possible flavors for that medicine to come in.
Real World: some Indians in the Amazon treat their eyes with a traditional potion applied with palm leaves. Brutally painful, the drug alters vision, giving the jungle's dense green walls greater texture and dimension. You could adapt this to desert or swamps, or other hard to navigate regions.