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•
tile lists, tessellations consisting of a list of windows, u sually polygonal windows;
• pixe llated tessellations, in which space is divided into pixels and each tile occupies a subset of
the pixel g rid.
Figure 4.2 7. Types of tessellations. Lef t: rectangular. Middle: tile list. Right: pixellated.
All three types of tessellation can be cr eated b y the command tess. To c reate a rectangular
tessellation:
tess(xgrid=xg, ygrid=yg)
where xg and yg are vectors of coordinates of vertical and horizontal lines determining a grid
of rectangles. Alternatively, if you want to subdivide a window W (usually but not necessarily ...