As you know the usage of shadow casting light, we will now bake the lighting and shadows in to a file. Create a new lambert material and set its diffuse color to white. Select the surface and the lambert material’s shading group node and go to hypershade > edit > convert to file texture options. Enable the bake shading group lighting bake shadows and set the X and y resolution to 1024 and file format to wither default or any other format like TGA. Now click on convert and close. As you can see the lighting is now baked into a file texture. You may now delete the light and render. You will see that the lighting is still here, thanks to the baked up light map.
