marenv::wake::GriddedSnapshot Struct Reference

#include <GriddedWake.h>

Collaboration diagram for marenv::wake::GriddedSnapshot:

Public Member Functions
bool	Deficit (double t, const double pos[3], double &deficit) const
bool	Sample (double t, const double pos[3], WakeSample &out) const
void	ToFrame (double t, const double pos[3], double xi[3]) const
bool	Stationary () const
	Whether the frame is at rest (velocity 0), so the snapshot does not change with t.
bool	MayReach (const WakeQueryRegion &region) const
void	Sketch (double t, FieldSketch &out) const
	Appends the grid's box at t (see WakeField::Sketch()).

Public Attributes
WakeFrame	frame
	Frame of the grid; pose(t) = origin + velocity (t - t0).
grid::UniformGrid3< double >	logRatio
	L = sum log(1 - d_i) at the nodes, frame coordinates.
double	sourceVelocity [3]
	Source velocity u_s of the sources, m/s, NED.
std::string	warning
	Resolution warning of WakeBuilder::Finish; empty when x_start >= 1.5 cells for every source.

Detailed Description

One immutable build of a gridded wake, produced by WakeBuilder::Finish (contract C4).

The grid holds the log velocity ratio L = sum log(1 - d_i) of the composed sources at its nodes, in frame coordinates (xi along frame.axes[0], the mean relative flow). A query interpolates L trilinearly and returns d = 1 - exp(L), which stays in [0, 1].

Member Function Documentation

Deficit()

bool marenv::wake::GriddedSnapshot::Deficit	(	double	t,
		const double	pos[3],
		double &	deficit
	)		const

Returns the deficit at a point.

Parameters

[in]	t	Simulation time, s; the frame is extrapolated to pose(t).
[in]	pos	Query position, m, world NED.
[out]	deficit	d in [0, 1]; 0 outside the grid.

Returns

true inside the grid, false outside.

MayReach()

bool marenv::wake::GriddedSnapshot::MayReach

(

const WakeQueryRegion &

region

)

const

Returns false only if the region lies wholly outside the grid at every time of its interval (see WakeField::MayReach()).

The grid's deficit is 0 outside it whatever the cutoff, so the test is the same at both tiers.

Sample()

bool marenv::wake::GriddedSnapshot::Sample	(	double	t,
		const double	pos[3],
		WakeSample &	out
	)		const

Returns the deficit and the snapshot's source velocity at a point (WakeBlendSnapshot).

Parameters

[in]	t	Simulation time, s; the frame is extrapolated to pose(t).
[in]	pos	Query position, m, world NED.
[out]	out	Deficit d in [0, 1], 0 outside the grid, and the source velocity u_s.

Returns

true inside the grid, false outside.

ToFrame()

void marenv::wake::GriddedSnapshot::ToFrame	(	double	t,
		const double	pos[3],
		double	xi[3]
	)		const

Transforms a world position into frame coordinates.

Parameters

[in]	t	Simulation time, s; the frame is extrapolated to pose(t).
[in]	pos	Position, m, world NED.
[out]	xi	Coordinates along frame.axes[0], axes[1] and axes[2] from pose(t), m.

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The documentation for this struct was generated from the following file:

• webfhsim/reloadrepos/marenv/include/marenv/wake/GriddedWake.h