Depending on the results, this should serve as a guide for achieving realistic renders of glasses containing liquids in future versions of indigo.
Below is a diagram with some associated requirements for the model.
Requirements:
a) need sufficient polygonisation of the curve here because sharp edges cause shading normal artifacts. For example 10-20 points may be needed on piecewise curve.
b)distance should be > 0.2mm
c) distance should be > 0.2mm.
Note that the distance between the glass and water surfaces in the walls of the glass needs only to be greater than 0.2mm, it should probably be about 1mm, depending on the width of the glass
d) distance between glass and z=0 plane should be in range [0.2mm, 1mm]
e) meniscus should be modelled
Addtionally:
f) all geometric (given by tri winding order) and smoothed normals should be as labelled.
g) total number of tris is expected to be in range 10000-60000
h) surfaces should be two-manifold and closed (not self-intersecting).
i) water and glass should be assigned different materials.
j) part of the surface of the water component should lie inside the glass as shown.
k) The model should be created in units of meters.
