An image processing apparatus includes a first shader configured to perform a light shading operation associated with at least one light source on a three-dimensional (3D) model at a first resolution to obtain a light shading result of the first resolution; a second shader configured to perform a surface shading operation on the 3D model at a second resolution different from the first resolution to obtain a surface shading result of the second resolution; and a processor configured to generate a rendering result by combining the light shading result of the first resolution with the surface shading result of the second resolution.