A note on solid surfaces

On machines utilizing the PHIGS graphics library (ESV, ESF & HP), the rendering of solid surfaces is controlled via a datablock called .active_surface. The entries in the datablock are as   follows:

1 Ambient coefficient [1.0].

2 Diffuse coefficient [1.0].

3 Specular coefficient [1.0].

4-6 Specular colour component in rgb [1.0 1.0 1.0].

7 Specular exponent [0.5].

8 Transparency [0.0].

9 Shading method [2]. Sets the PHIGS+ shading method. The possible values are:

1 No shading. This means that nothing appears on the screen.

2 Colour interpolation shading.

3 Dot product interpolation shading.

4 Normal interpolation shading.

10 Shading style [1] Sets the PHIGS+ shading style. The only sensible value to use is

1 solid

11 Reflectance equation [4] Sets the PHIGS+ interior reflectance equation parameters. The possible values are:

1 No reflectance calculation performed.

2 Use ambient term

3 Use ambient and diffuse terms.

4 Use ambient, diffuse and specular terms.

There is not yet any user interface for changing the active surface. If for some reason, therefore, you don't see any solids appearing on the screen when you thought something would, it is possible that the values in the database have been corrupted. You should then try deleting the datablock .active_surface. O will then reset things to a sensible   state.