Virtual Models

Lights in MuPAD and JavaView

Comparison of MuPAD and JavaView Lights

The lightning systems in MuPAD and JavaView are very similar. With some minor exceptions we can match these systems reasonably well. In June 2005 the light concept in JavaView was expanded. The spot light was added and a number of new light features was created. The table below shows summary of both systems.

MuPAD	JavaView	Comment
Ambient light	Ambient light	Both light types are the same, xvc2jvx converts ambient light into an ambient light with the same intensity.
Point light	Point light	Point lights in both systems are almost the same, xvc2jvx converts point light from MuPAD into a point light in JavaView
Spot light	Spot light	Spot light in JavaView has a more sophisticated concept than in MuPAD. We can define the angle of the spot as well as additional space around the light spot, in JavaView called corona, where the light falls off from full intensity to 0.
Distance light	Direction light	Distance light and direction lights share the same features, xvc2jvx converts the distance light into a direction light.
	Head light	This is unique JavaView light. This light is attached to the camera and does not move while rotating the model. It behaves like direction light. Note: in JavaView point lights and direction lights, by default, have a permanent position in respect to the coordinate system.
	Sky light	This is another unique JavaView light. It simulates sun light and enlightens the scene from the top. Its properties are similar to the direction light. This light does not move while rotating the scene.

Moreover, in JavaView we have two predefined sets of lights: default set of lights and RGB lights set.

JavaView specific sets of lights


Set of lights	Parameters	Comments
Default lights	Contains: Sky light, intensity 0.3 Head light, intensity 0.8	Default lights in many situations produce a bit dark scene. A good improvement could be adding one ambient light (intensity 0.2).
RGB lights	Contains: Red light 0.8, location [2,0,2] Green light 0.8, location [2,2,2] Blue light 0.8, location [0,2,2]	In some situations the scene with RGB lights only is a bit dull. Adding an ambient light can slightly improve the scene. Each of these lights has properties similar to a direction light.