14_custom_field_initializer.cpp File Reference

Example: Custom field initialization patterns. More...

#include <cmath>
#include <iostream>
#include <openpfc/openpfc.hpp>

Include dependency graph for 14_custom_field_initializer.cpp:

Classes
struct	my_project::VortexPattern
	Lamb-Oseen vortex pattern. More...
struct	my_project::GaussianBump
	3D Gaussian bump More...
struct	my_project::CheckerboardPattern
	3D checkerboard pattern More...

Namespaces
namespace	my_project

Functions
double	evaluate_vortex (const my_project::VortexPattern &pattern, const Real3 &pos)
	Evaluate vortex pattern at given position.
double	evaluate_gaussian (const my_project::GaussianBump &pattern, const Real3 &pos)
	Evaluate Gaussian bump at given position.
double	evaluate_checkerboard (const my_project::CheckerboardPattern &pattern, const Real3 &pos)
	Evaluate checkerboard at given position.
void	example_vortex_pattern ()
void	example_gaussian_bump ()
void	example_checkerboard ()
int	main ()

Variables
constexpr double	M_PI = 3.14159265358979323846

Detailed Description

Example: Custom field initialization patterns.

This example demonstrates how to create custom field initialization patterns using simple structs and evaluation functions. We show three physical patterns:

1. Lamb-Oseen Vortex - Rotating fluid vortex with viscous core
2. Gaussian Bump - Localized concentration or temperature field
3. Checkerboard - Periodic alternating pattern

Key Concept: Struct-Based Patterns

Instead of inheritance hierarchies, we use simple structs with public data. This follows OpenPFC's "structs + free functions" philosophy.

Integration with OpenPFC

For full integration with DiscreteField/World APIs using ADL, see:

• docs/extending_openpfc/adl_extension_patterns.md
• examples/17_custom_coordinate_system.cpp

This simplified example focuses on the pattern concept itself.

Function Documentation

evaluate_checkerboard()

double evaluate_checkerboard	(	const my_project::CheckerboardPattern &	pattern,
		const Real3 &	pos
	)

Evaluate checkerboard at given position.

Parameters

pattern	The checkerboard configuration
pos	Physical position to evaluate at

Returns

High or low value depending on position

evaluate_gaussian()

double evaluate_gaussian	(	const my_project::GaussianBump &	pattern,
		const Real3 &	pos
	)

Evaluate Gaussian bump at given position.

Parameters

pattern	The Gaussian configuration
pos	Physical position to evaluate at

Returns

Field value at position

evaluate_vortex()

double evaluate_vortex	(	const my_project::VortexPattern &	pattern,
		const Real3 &	pos
	)

Evaluate vortex pattern at given position.

Parameters

pattern	The vortex configuration
pos	Physical position to evaluate at

Returns

Tangential velocity at position