Lights in MuPAD and JavaView
White box with spot lights
I use here three spot lights, each with different color: red, green and blue. The result in MuPAD is rather bad. It seems that spot lights doesn't work well in this case. The same is in JavaView. However, here the reason is known -- too small radius and corona of each light. Default parameters may not work well with each model. However, after some minor changes the model looks acceptable (see far below).
MuPAD
Image obtained in MuPAD using spot lights. The scene is too dark, light colors are missing.
JavaView
The same model converted to JavaView without any changes. Although, in this scene the three spot lights are on, their radii are too narrow to produce the adequate lighting of the cube. Note: JavaView uses mesh vertices to calculate how much of light is reflected from the surface. In this example, each spot light falls on one side of the cube without touching vertices of the side.
JavaView
The same model again, but I changed the radius of the light to 60 deg, corona to 45 deg. The model looks quite acceptable.