AbstractVisualizing the flow of air or fluids is especially challenging because of their transparency and possible high velocity. Complex patterns are created when the flow is over or around an object. Our aim is to visualize the flow in three dimensions, eliminating the need for mentally piecing the flow from two‐dimensional slices. We have applied the well‐known ray casting technique to visualize the flow around an aircraft wing. During ray casting, when the ray does not intercept the lattice points, linear and B‐spline hyperpatch interpolations are used to estimate the colour. We describe the shading equation, and compare the linear and the B‐spline hyperpatch interpolation schemes during ray casting. Several images are produced to show the difference in the image quality of these two methods, and their image generati