This paper presents an inverse daylighting model devoted to the design of building openings. The inverse daylighting model includes sky lighting as well as light reflected by surroundings, and therefore combines near-field and far-field light sources. Input data is a heterogeneous lighting distribution on indoor faces called "lighting intention". Openings are considered as a set of intermediate anisotropic light sources. Therefore the geometric reconstruction problem is seen as a source emittance problem. A pin-hole model generates anisotropic light sources and computes light contribution on each indoor faces. An image metric evaluates the distance between this light contribution and lighting intention. Intermediate light sources which have the smallest distance are selected to be part of opening, and therefore define opening shape. This technique is intended to aid opening design in the early stage of architectural design. Our model is validated by test cases and illustrated by a case study in order to show the opening reconstruction process.