A computer-implemented method including: receiving visible-light images captured from viewpoints using visible-light camera(s); creating 3D model of real-world environment, wherein 3D model stores colour information pertaining to 3D points on surfaces of real objects (204); dividing 3D points into groups of 3D points, based on at least one of: whether surface normal of 3D points in group lie within predefined threshold angle from each other, differences in materials of real objects, differences in textures of surfaces of real objects; for group of 3D points, determining at least two of visible-light images in which group of 3D points is captured from different viewpoints, wherein said images are representative of different surface irradiances of group of 3D points; and storing, in 3D model, information indicative of different surface irradiances.