Simulations - Practical Rendering and Computation with Direct3D 11 - page 545

Figure 1 2.6. Perimeter threads overlapping with adjacent thread groups, depicted with an 8x8 thread group
for visualization.
are used strictly to update the current grid of fluid columns, as we identified in Figure 12.4.
The concept of using updated thread groups, with the perimeter threads shown in adjacent
thread groups, is shown in Figure 12.6.
Fluid Simulation Update Phase
With a general threading model in hand, we can move on to determining the actual work
that each individual thread will perform. Each thread will perform four actions. Depending
on where a thread is located in the thread group and the overall simulation grid, some of
these steps may be reduced or skipped. We will cover these details as they arise in the fol-
lowing discussion.