Need to have :
Simplicity, all in one box. less is more.
Alpha is automatic with PNG textures.
Displacement Mapping
Volumetric material : Plasma, cloud, fog (there is actually a Fog function in Sketchup, would be good to work with it).
Material Preview
Nice to Have :
Skatter Mapping through assigned textures... eg... grass texture, equivalent becomes skattered real displaced grass or fur.
Real World descriptions instead of just vague numbered values.
examples of real world descriptions for reflectivity :
0% <- dull(raw, hewn), satin (brushed, honed, flat), semi-gloss (lacquer), gloss (polished), chrome, mirror -> 100%
examples of real world descriptions for bump / displacement level :
working with the units : ie. nm, mm, cm, m.
invert tick box.
examples of real world descriptions for opacity (affects opacity in Sketchup's native levels) : 0% <- air, clear water (bump map required), clear glass, tinted glass, frosted glass (entering into SSS territory), wax, skin, full opaque -> 100%
IOR / refraction : Thin glass (windows), thick glass, water, plastic, diamond.
Emmissivity : Lumens based on a certain average size of an emmissive material ie. 10mm x 10mm <- glowworm, phosphorous strips, burning bbq coals, naked flame, fluorescent, incandescent 40W, halogen 50w, halogen 100w, halogen 200W, sodium street lamp, 400W flood lamp, lighthouse lamp, sunlight ->. and colour temperature in terms of Kelvins. adding a filter can affect the colour.