edu.d.umn.geometry
Class ElevationModel

java.lang.Object
  javax.media.j3d.SceneGraphObject
      javax.media.j3d.Node
          javax.media.j3d.Group
              javax.media.j3d.BranchGroup
                  edu.d.umn.geometry.ElevationModel

All Implemented Interfaces:

ElevationModelInterface

public class ElevationModel
extends javax.media.j3d.BranchGroup
implements ElevationModelInterface

ElevationModel is a specialization of a BranchGroup that holds Java3D geometry objects representing a terrain map. The map is divided into segments each segment contains a Level-of-Detail switch containing the geometry for the segment in three levels of detail. This allows for faster drawing and navigation of the model as a whole.

See Also:

LODSegment

Field Summary

protected float	deltaCol space in meters between each column of elevation data
protected float	deltaRow space in meters between each row of elevation data
float	east_X maximum X coordinate
float	exageration Factor each elevation reading is multiplied by when drawing the model.
protected ElevationFile	file The ElevationFile that holds the data.
GroundCoordinates	groundCoordinates GroundCoordinates for the model, contains the lat/long of the four corners in arc seconds
protected int	maxElevation maximum elevation in meters
protected int	minElevation minimum elevation in meters
java.lang.String	name geographic name or title of the data
float	north_Z minimum Z coordinate
static int	SECONDS_PER_SEGMENT number of seconds high/wide of each segment is
protected LODSegment[][]	segments two dimensional array of segments comprising the model data
float	south_Z maximum Z coordinate, note, positive Z axis is in the south due to Java3D
float	west_X minimum X coordinate

Fields inherited from class javax.media.j3d.BranchGroup

ALLOW_DETACH

Fields inherited from class javax.media.j3d.Group

ALLOW_CHILDREN_EXTEND, ALLOW_CHILDREN_READ, ALLOW_CHILDREN_WRITE, ALLOW_COLLISION_BOUNDS_READ, ALLOW_COLLISION_BOUNDS_WRITE

Fields inherited from class javax.media.j3d.Node

ALLOW_AUTO_COMPUTE_BOUNDS_READ, ALLOW_AUTO_COMPUTE_BOUNDS_WRITE, ALLOW_BOUNDS_READ, ALLOW_BOUNDS_WRITE, ALLOW_COLLIDABLE_READ, ALLOW_COLLIDABLE_WRITE, ALLOW_LOCAL_TO_VWORLD_READ, ALLOW_LOCALE_READ, ALLOW_PARENT_READ, ALLOW_PICKABLE_READ, ALLOW_PICKABLE_WRITE, ENABLE_COLLISION_REPORTING, ENABLE_PICK_REPORTING

Constructor Summary

protected	ElevationModel() Empty constructor.
	ElevationModel(java.lang.String aFileName, StatusWindow stat) Sets up and compiles the ElevationModel.

Method Summary

void	changeExageration(float amount) Change the exageration of the model.
protected void	createLODSegments(StatusWindow stat) Initializes the LODSegment array to a number of columns and rows based on the GroundCoordinates length and width in seconds and the SECONDS_PER_SEGMENT.
float	getElevationAt(float x, float z) Fetches the elevation at a particular location on the terrain map given the x,z coordinates.
float	getMaxElevation() retrieve the model maximum elevation, adjusted by the elevation exageration
float	getMinElevation() retrieve the model minimum elevation, adjusted by the elevation exageration
float	getModelLength() retrieve the model length, distance in meters from west to east
float	getModelWidth() retrieve the model width, distance in meters from south to north
float	getQuadResolution() Retrieve the resolution of the dem.
LODSegment	getSegment(int col, int row) Returns an LODSegment located at [row][col]
void	recalcNormals() Recalculates the normal values so that the lighting effects change when the elevation exageration change.
void	setColor(java.awt.Color color) Changes the color of the model.
void	setTexture(javax.media.j3d.Texture2D tex) Change the texture of the model.

Methods inherited from class javax.media.j3d.BranchGroup

cloneNode, compile, detach, pickAll, pickAll, pickAllSorted, pickAllSorted, pickAny, pickAny, pickClosest, pickClosest

Methods inherited from class javax.media.j3d.Group

addChild, getAllChildren, getAlternateCollisionTarget, getChild, getCollisionBounds, indexOfChild, insertChild, moveTo, numChildren, removeAllChildren, removeChild, removeChild, setAlternateCollisionTarget, setChild, setCollisionBounds

Methods inherited from class javax.media.j3d.Node

cloneTree, cloneTree, cloneTree, cloneTree, cloneTree, cloneTree, duplicateNode, getBounds, getBoundsAutoCompute, getCollidable, getLocale, getLocalToVworld, getLocalToVworld, getParent, getPickable, setBounds, setBoundsAutoCompute, setCollidable, setPickable

Methods inherited from class javax.media.j3d.SceneGraphObject

clearCapability, clearCapabilityIsFrequent, duplicateSceneGraphObject, getCapability, getCapabilityIsFrequent, getName, getUserData, isCompiled, isLive, setCapability, setCapabilityIsFrequent, setName, setUserData, toString, updateNodeReferences

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

groundCoordinates

public GroundCoordinates groundCoordinates

GroundCoordinates for the model, contains the lat/long of the four corners in arc seconds

west_X

public float west_X

minimum X coordinate

east_X

public float east_X

maximum X coordinate

south_Z

public float south_Z

maximum Z coordinate, note, positive Z axis is in the south due to Java3D

north_Z

public float north_Z

minimum Z coordinate

SECONDS_PER_SEGMENT

public static final int SECONDS_PER_SEGMENT

number of seconds high/wide of each segment is

See Also:

Constant Field Values

deltaRow

protected float deltaRow

space in meters between each row of elevation data

deltaCol

protected float deltaCol

space in meters between each column of elevation data

exageration

public float exageration

Factor each elevation reading is multiplied by when drawing the model. Makes elevation differences stand out

minElevation

protected int minElevation

minimum elevation in meters

maxElevation

protected int maxElevation

maximum elevation in meters

name

public java.lang.String name

geographic name or title of the data

segments

protected LODSegment[][] segments

two dimensional array of segments comprising the model data

file

protected ElevationFile file

The ElevationFile that holds the data.

Constructor Detail

ElevationModel

protected ElevationModel()

Empty constructor.

ElevationModel

public ElevationModel(java.lang.String aFileName,
                      StatusWindow stat)
               throws java.io.IOException

Sets up and compiles the ElevationModel.

Parameters:

aFileName - full name of the file to use.

stat - Reference to the status window to display loading status.

Throws:

java.io.IOException - Thrown if the file does not exist.

Method Detail

createLODSegments

protected void createLODSegments(StatusWindow stat)

Initializes the LODSegment array to a number of columns and rows based on the GroundCoordinates length and width in seconds and the SECONDS_PER_SEGMENT. Also stitches together the top and right sides to create a smooth mesh.

getElevationAt

public float getElevationAt(float x,
                            float z)

Fetches the elevation at a particular location on the terrain map given the x,z coordinates. X,Z coordinates represent the distance in meters from the center of the terrain image

Specified by:

getElevationAt in interface ElevationModelInterface

Parameters:

x - x coordinate

z - z coordinate

Returns:

the elevation (y coordinate) in meters (adjusted for exageration)

getModelLength

public float getModelLength()

retrieve the model length, distance in meters from west to east

Specified by:

getModelLength in interface ElevationModelInterface

Returns:

the length in meters

getModelWidth

public float getModelWidth()

retrieve the model width, distance in meters from south to north

Specified by:

getModelWidth in interface ElevationModelInterface

Returns:

the width in meters

getMaxElevation

public float getMaxElevation()

retrieve the model maximum elevation, adjusted by the elevation exageration

Specified by:

getMaxElevation in interface ElevationModelInterface

Returns:

the adjusted maximum elevation in meters

getMinElevation

public float getMinElevation()

retrieve the model minimum elevation, adjusted by the elevation exageration

Specified by:

getMinElevation in interface ElevationModelInterface

Returns:

the adjusted minimum elevation in meters

setTexture

public void setTexture(javax.media.j3d.Texture2D tex)

Change the texture of the model.

Parameters:

tex - The Texture2D to change to.

changeExageration

public void changeExageration(float amount)

Change the exageration of the model.

Parameters:

amount - The amount to change the exageration to.

getSegment

public LODSegment getSegment(int col,
                             int row)

Returns an LODSegment located at [row][col]

Parameters:

col - the column of the LODSegment

row - the row of the LODSegment

Returns:

An LODSegment located at [row][col]

getQuadResolution

public float getQuadResolution()

Retrieve the resolution of the dem. Typically will be 24k for an SDTS transfer.

Returns:

The resolution of the quad data.

recalcNormals

public void recalcNormals()

Recalculates the normal values so that the lighting effects change when the elevation exageration change.

setColor

public void setColor(java.awt.Color color)

Changes the color of the model.

Parameters:

color - Desired color to change to.