Advection Callback

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An AdvectionCallback<NumericType, D> runs user code around each advection step. Attach it to a process model with setAdvectionCallback(...); the process sets its domain member before execution.

#include <process/psAdvectionCallback.hpp>

template <typename T, int D>
class SaveSurface : public viennaps::AdvectionCallback<T, D> {
public:
  bool applyPostAdvect(T processTime) override {
    this->domain->saveSurfaceMesh("latest_surface.vtp");
    return true;
  }
};

With an existing model:

model->setAdvectionCallback(
    viennaps::SmartPointer<SaveSurface<double, 2>>::New());

The same callback can be implemented in Python:

import viennaps as vps

class SaveSurface(vps.AdvectionCallback):
    def __init__(self):
        super().__init__()

    def applyPostAdvect(self, process_time):
        self.domain.saveSurfaceMesh("latest_surface.vtp")
        return True

callback = SaveSurface()
model.setAdvectionCallback(callback)

Keep the Python callback alive while the process runs. These examples overwrite one snapshot; use distinct filenames to retain a time series.

Hook	When it runs in analytic and flux processes
applyPreAdvect(processTime)	Before advection, with the elapsed process time.
applyPostAdvect(processTime)	After advection, with the updated elapsed process time.

Both hooks return a boolean. Return true to continue or false to stop an analytic or flux process early. The post-advection argument is cumulative process time, despite the advectionTime name in the base-class declaration.

Callback-only execution

For a model with a callback and a Process duration of zero, the callback-only strategy invokes applyPreAdvect(0) once. It does not advect the surface or invoke applyPostAdvect, and it does not use the returned boolean to set the process result. This is how ion implantation and annealing run volume calculations. Those models already own a callback; replacing it replaces their volume operation.