Terrain modelling and colouring with simplex noise. Real-time shading (phong) + ambient occlusion / sky shading + post process (like fog, shadowing). Ray traced on CPU but entirely exportable to GPU for real time rendering. To render a sunset picture, we added radial interpolation around the sunshine, noise on the sky texture and colour on specular, and used raytracing information for the horizon line at the top of the far mountains.
We can also switch between real time and pre-calculated. In the pre-calculated mode the light are not calculated for every camera movement and so we have a better fps.