I combined forces with Cristina Barna on two separate 3D explorations of chocolate and another of wheat. Cristina developed the initial concept and styleframes, then I created the 3D renders based on those frames and passed my renders back to Cristina to bring it all together in compositing.
The 3D was done entirely in Houdini using mainly Arnold renderer with a few passes coming from Redshift. The chocolate slow motion pour scene was the most challenging. I have a lot of experience with small scale liquid simulation but not much in slow motion. Slow motion meshes are unforgiving and don't leave room to hide mesh flickering, popping, or imperfections. To top it off, liquid chocolate is of course very reflective which reveals surface detail issues. At one point, I even tried to simulate using vellum cloth since the layering chocolate seemed somewhat cloth-like but that was an act of desperation.
The chocolate is a FLIP simulation with variable viscosity that increases over time. The logic being that liquid chocolate would be heated and gain viscosity while losing temperature as it's poured out. My main goal with the simulation was to replicate the stacking "ribbons" of chocolate folding over each other which was difficult to maintain with heavy smoothing. The final mesh is the result of an elaborate combination of VDB mesh operations including varying levels of overall smoothing based on different areas of the volume and other attributes. I used several steps of analysis to isolate areas of the mesh based on curvature and position in order to produce high smoothing on the outer folds of chocolate, while maintaining as much detail on the sides as possible.