Mixed Matters

Monolith has the ability to generate voxel data from source geometry such
as points, lines, curves, planes, and BREPs. The process involves measuring
the distance from each voxel to the nearest point on the source geometry.
After passing through a scalar decay function (i.e. linear, square, exponential,
or power), these distances are normalised and assigned to the corresponding
shape or material ratio channel.
Figure 4: Volumetric model showing the underlying source geometry on the left and the resultant composite
voxel model on the right.
Mesh geometry can also be used to inform voxel densities. The mesh geometry
can be created in any 3D modelling software as a watertight mesh
surface. It can then be imported into Monolith in one of two ways. The first
assigns a voxel density of 1.0 to every unit that falls within the interior of the
mesh geometry; allocating a value of 0.0 to all other voxels.
The second method uses the mesh geometry as a mask. When imported
into Monolith, it overrides the shape channel in the final composition step.
For instance, a designer could create a mesh object in a surface modelling
software and bring it into Monolith as a mask mesh. S/he could then use
Monolith to describe how materials would vary within this shape; something
that requires volumetric rather than surface modelling techniques. The
advantage of using a mask mesh is that it has the ability to capture sharp
corners and discontinuities better than voxel-based contours.
Hybrid Operations
Of course, being a hybrid modelling environment means that there are techniques
that blur the boundary between each fundamental paradigm. Lofting
or Sweeping, for example, are techniques which are fundamental parts of
the CAD modelling vocabulary. They work by blending cross-sectional shapes
(i.e. curves) along a path, ultimately creating a surface boundary representation.
Monolith augments this approach by using raster-based bitmaps, which
can represent fuzzy or continuously varied gradients as underlying cross-
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