Our perception of a space is chiefly determined by the surfaces within it and the relative brightness of them. In particular, vertical surfaces at eye level give us our primary cue to the brightness of a space, closely followed by the ceiling. Texture comes in two forms as far as light is concerned: Firstly that light can help reveal (or obliterate!) texture within the surfaces and objects of the space. Secondly, light itself can have a textural quality – think dappled sunlight on the ground beneath a large tree.
It is important therefore to think about which surfaces within a space you wish to light, and how the various surfaces there will balance each other. What is the hierarchy, and what type of light do you want to fall on them? Revealing a textured surface can often be achieved by ‘grazing’ a surface with light from point sources. Alternatively, you might want to deliberately minimise texture within your scheme. White Cube Gallery for example is lit in such a way that the lighting is almost completely homogeneous.