com.metsci.glimpse.support.projection

Class LatLonProjection

java.lang.Object

com.metsci.glimpse.support.projection.LatLonProjection

All Implemented Interfaces:

InvertibleProjection, Projection

public class LatLonProjection
extends Object
implements InvertibleProjection

A projection which maps a texture with data values spaced uniformly in lat/lon space onto a flat plane defined by the provided GeoProjection.

Author:

ulman

Field Summary

Fields

Modifier and Type	Field and Description
static double	SIZE_DOWNSAMPLE

Constructor Summary

Constructors

Constructor and Description
LatLonProjection(GeoProjection projection, double minLat, double maxLat, double minLon, double maxLon)
LatLonProjection(GeoProjection projection, double minLat, double maxLat, double minLon, double maxLon, boolean latIsX)

Method Summary

Modifier and Type	Method and Description
int	getSizeX(int textureSizeX) Returns the number of quads in the x direction that the array of data (the texture) should be broken into.
int	getSizeY(int textureSizeY)
double	getTextureFractionX(double vertexX, double vertexY) Given a position in physical units, return the corresponding location within a rectangular array of data.
double	getTextureFractionY(double vertexX, double vertexY)
void	getVertexXY(double textureFractionX, double textureFractionY, float[] resultXY) Given a position in a rectangular array of data (the texture), return the corresponding location in physical units.
void	getVertexXYZ(double textureFractionX, double textureFractionY, float[] resultXYZ) Given a position in a rectangular array of data (the texture), return the corresponding location in physical units.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

SIZE_DOWNSAMPLE

public static final double SIZE_DOWNSAMPLE

See Also:

Constant Field Values

Constructor Detail

LatLonProjection

public LatLonProjection(GeoProjection projection,
                        double minLat,
                        double maxLat,
                        double minLon,
                        double maxLon,
                        boolean latIsX)

LatLonProjection

public LatLonProjection(GeoProjection projection,
                        double minLat,
                        double maxLat,
                        double minLon,
                        double maxLon)

Method Detail

getVertexXY

public void getVertexXY(double textureFractionX,
                        double textureFractionY,
                        float[] resultXY)

Description copied from interface: Projection

Given a position in a rectangular array of data (the texture), return the corresponding location in physical units. The position is given as relative coordinates, with 0.0 indicating the 0th data index and 1.0 indicating the last data index.

This method computes the physical coordinate of the data at (textureFractionX, textureFractionY), and stores them in the resultXY output parameter.

Specified by:

getVertexXY in interface Projection

Parameters:

textureFractionX - a relative x index (from 0.0 to 1.0) into the data array

textureFractionY - a relative y index (from 0.0 to 1.0) into the data array

resultXY - output parameter to be populated with physical coords of the data

getVertexXYZ

public void getVertexXYZ(double textureFractionX,
                         double textureFractionY,
                         float[] resultXYZ)

Description copied from interface: Projection

Given a position in a rectangular array of data (the texture), return the corresponding location in physical units. The position is given as relative coordinates, with 0.0 indicating the 0th data index and 1.0 indicating the last data index.

This method computes the physical coordinate of the data at (textureFractionX, textureFractionY), and stores them in the resultXYZ output parameter.

Assigning z coordinates to vertices can be useful even for 2D graphics. For example, it can be used together with z-clipping to avoid rendering some facets.

Specified by:

getVertexXYZ in interface Projection

Parameters:

textureFractionX - a relative x index (from 0.0 to 1.0) into the data array

textureFractionY - a relative y index (from 0.0 to 1.0) into the data array

resultXYZ - output parameter to be populated with physical coords of the data

getSizeX

public int getSizeX(int textureSizeX)

Description copied from interface: Projection

Returns the number of quads in the x direction that the array of data (the texture) should be broken into. If the projection is linear in the x direction (for example, if the data/texture is simply being displayed on a rectangle) then only one quad is needed.

For more complicated projections, the value returned essentially defines the granularity or resolution of the projection (since the projection will ultimately be approximated when displayed by drawing a set of small quads).

Specified by:

getSizeX in interface Projection

Parameters:

textureSizeX - the length of the data array (the texture) in the x direction

Returns:

the number of quads in the x direction to draw

getSizeY

public int getSizeY(int textureSizeY)

Specified by:

getSizeY in interface Projection

Parameters:

textureSizeY - the length of the data array (the texture) in the y direction

Returns:

the number of quads in the y direction to draw

See Also:

Projection.getSizeX( int )

getTextureFractionX

public double getTextureFractionX(double vertexX,
                                  double vertexY)

Description copied from interface: InvertibleProjection

Given a position in physical units, return the corresponding location within a rectangular array of data. The corresponding location is returned in relative coordinates, with 0.0 indicating the 0th data index and 1.0 indicating the last data index.

This method returns the first (row) index of the data at (vertexX, vertexY).

Specified by:

getTextureFractionX in interface InvertibleProjection

Parameters:

vertexX - a x coordinate in physical space

vertexY - a y coordinate in physical space

Returns:

a relative index (from 0.0 to 1.0) into the data array

getTextureFractionY

public double getTextureFractionY(double vertexX,
                                  double vertexY)

Specified by:

getTextureFractionY in interface InvertibleProjection

Parameters:

vertexX - a x coordinate in physical space

vertexY - a y coordinate in physical space

Returns:

the relative y index (from 0.0 to 1.0) into the data array

See Also:

InvertibleProjection.getTextureFractionX( double, double )