org.opengis.geometry.coordinate

Interface GriddedSurface

All Superinterfaces:

GenericSurface, ParametricCurveSurface, SurfacePatch

All Known Subinterfaces:

BicubicGrid, BilinearGrid, BSplineSurface, Cone, Cylinder, Sphere

@UML(identifier="GM_GriddedSurface",
     specification=ISO_19107)
public interface GriddedSurface
extends ParametricCurveSurface

A parametric curve surface defined from a rectangular grid in the parameter space. The rows from this grid are control points for horizontal surface curves; the columns are control points for vertical surface curves. The working assumption is that for a pair of parametric coordinates (s, t), that the horizontal curves for each integer offset are calculated and evaluated at s. This defines a sequence of control points:

<c_n(s) : s = 1 … columns>

From this sequence, a vertical curve is calculated for s, and evaluated at t. In most cases, the order of calculation (horizontal-vertical versus vertical-horizontal) does not make a difference. Where it does, the horizontal-vertical order shall be the one used.

The most common case of a gridded surface is a 2D spline. In this case the weight functions for each parameter make order of calculation unimportant:

TODO: copy equations there

Logically, any pair of curve interpolation types can lead to a subtype of GriddedSurface. The sub-interfaces provided in this package define some of the most commonly encountered surfaces that can be represented in this manner.

Since:

GeoAPI 2.0

Author:

Martin Desruisseaux (IRD)

Method Summary

Modifier and Type	Method and Description
int	getColumns() Returns the number of columns in the parameter grid.
PointGrid	getControlPoints() Returns the doubly indexed sequence of control points, given in row major form.
int	getRows() Returns the number of rows in the parameter grid.

Methods inherited from interface ParametricCurveSurface

getHorizontalCurveType, getVerticalCurveType, horizontalCurve, surface, verticalCurve

Methods inherited from interface SurfacePatch

getBoundary, getInterpolation, getNumDerivativesOnBoundary, getSurface

Methods inherited from interface GenericSurface

getArea, getPerimeter, getUpNormal

Method Detail

getControlPoints

@UML(identifier="controlPoint",
     obligation=MANDATORY,
     specification=ISO_19107)
PointGrid getControlPoints()

Returns the doubly indexed sequence of control points, given in row major form. There is no assumption made about the shape of the grid. For example, the positions need not effect a "2½D" surface, consecutive points may be equal in any or all of their ordinates. Further, the curves in either or both directions may close.

getRows

@UML(identifier="rows",
     obligation=MANDATORY,
     specification=ISO_19107)
int getRows()

Returns the number of rows in the parameter grid.

getColumns

@UML(identifier="columns",
     obligation=MANDATORY,
     specification=ISO_19107)
int getColumns()

Returns the number of columns in the parameter grid.