How does round vision actually work like in round

Wide-angle or "round" images map a wide field of view from a spherical scene onto a flat image using non-linear projection formulas. Common mappings include: - Equirectangular: maps latitude and longitude linearly to x and y. It preserves neither angles nor areas uniformly, so shapes near the poles stretch vertically. - Stereographic: projects the sphere from one pole onto a plane. It is conformal (preserves angles and small shapes locally), but it enlarges areas far from the projection point and bends straight lines that do not pass through the projection center. - Fisheye (equidistant, equisolid-angle, etc.): maps angle from the optical axis to radius in the image. Different fisheye formulas preserve different properties (e.g., equal angles or equal solid angles) but all produce strong scale variation with viewing angle. Trade-offs and visible effects - Angle vs. area: No flat-map projection can preserve both everywhere. Conformal projections keep local angles intact but distort relative sizes; equal-area projections keep areas correct but distort shapes. - Straight lines: Only lines through the projection center remain straight. Other great circles on the sphere generally appear as curves in the image. - Scale variation: Objects near the image edge are stretched or magnified compared with those near the center; the amount depends on the chosen projection. In short: wide-angle views require choosing a projection that preserves some geometric property while necessarily distorting others, producing curved lines and nonuniform scaling across the image. (For technical references, see Snyder, J.P., "Map Projections — A Working Manual" (USGS), and Gentile et al., "Fisheye Lens Projection Models and Calibration".)