Shrimp Shader Generator FLTK2 GUI (SVN)

Updated light blocks so that the user can toggle custom lights as nondiffuse/nonspecular. Updated root block source so that light shaders have a default output uniform float __nondiffuse/__nonspecular shader parameter, which the blocks override. Updated the glass shader block and the function, so that it returns both color and transparency - transmission based shadows based on Alan Warren's port of the VEX shader by Mario Marengo.

Small update to glass function, maximum continuation is float.

Only 3delight seems to product correct internal reflections without the need to reverse N if the ray is travelling inside medium, other renderers need reversed N, otherwise fresnel() will go the way of the wouwous.

Added bias for glass's environment().

Typo in vmax/vmin, return type should float, not color.

Updated glass shading function. Still needs transmission for shadow colors, and eventually dispersion. Added luminance block.

Added stippled lines for active connections (pad>pointer).

Fixed the tooltip color/background readability problem, tweaked some widget's colors. Added rounded corners blocks.

Added a new default (dark) theme, flat/border-boxxed.

Changed the UI a bit, added widgets for normal, point, matrix types. Tweaked existing string and color type widgets. Changed colors for blocks, and shape and colors for groups.