default diffuse in Material

[jvail]

Would it be a very inconvenient change for plantgl users if you'd change the default diffuse to 1?

The ambient would then just become the color w/o any influence of diffuse. I guess we should then also update the default Material ambient by applying the current diffuse default to rgb values.

[fredboudon]

With a diffuse of 1, this means that the color of an object will be the same if it lighted or not. This is not very convenient to see the volumetric aspect of the objects.