A color triangle is an arrangement of colors within a triangle, based on the additive combination of three primary colors at its corners. An additive color space defined by three primary colors has a chromaticity gamut that is a color triangle, when the amounts of the primaries are constrained to be nonnegative. en.wikipedia.org А теперь по-русски: Тобиас Майер расположил в углах треугольника...