Understanding WCAG2.0 Colour Contrast Requirements Through 3D Colour Space Visualisation

Abstract

Sufficient contrast between text and background is needed to achieve sufficient readability. WCAG2.0 provides a specific definition of sufficient contrast on the web. However, the definition is hard to understand and most designers thus use contrast calculators to validate their colour choices. Often, such checks are performed after design and this may be too late. This paper proposes a colour sele ction approach based on three - dimensional visualis ation of the colour space. The complex non - linear relationships between the colour components become comprehendible when viewed in 3D . The method visualis es the available colour s in an intuitive manner and allows designers to check a colour against the set of other valid colour s. Unlike the contrast calculators, the proposed method is proactive and fun to use. A colour space builder was developed and the resulting models were viewed with a point cloud viewer . The technique can be used as both a design tool and a pedagogical aid to teach colour theory and design.