com.jme3.terrain.heightmap

Class AbstractHeightMap

java.lang.Object

com.jme3.terrain.heightmap.AbstractHeightMap

All Implemented Interfaces:

HeightMap

Direct Known Subclasses:

CombinerHeightMap, FaultHeightMap, FluidSimHeightMap, FractalTileLoader.FloatBufferHeightMap, HillHeightMap, ImageBasedHeightMap, MidpointDisplacementHeightMap, ParticleDepositionHeightMap, RawHeightMap

public abstract class AbstractHeightMap
extends java.lang.Object
implements HeightMap

AbstractHeightMap provides a base implementation of height data for terrain rendering. The loading of the data is dependent on the subclass. The abstract implementation provides a means to retrieve the height data and to save it. It is the general contract that any subclass provide a means of editing required attributes and calling load again to recreate a heightfield with these new parameters.

Field Summary

Fields

Modifier and Type	Field and Description
protected float	filter The filter is used to erode the terrain.
protected float[]	heightData Height data information.
protected float	heightScale Allows scaling the Y height of the map.
static float	NORMALIZE_RANGE The range used to normalize terrain
protected int	size The size of the height map's width.

Constructor Summary

Constructors

Constructor and Description
AbstractHeightMap()

Method Summary

Modifier and Type	Method and Description
void	erodeTerrain() erodeTerrain is a convenience method that applies the FIR filter to a given height map.
float[]	findMinMaxHeights() Find the minimum and maximum height values.
void	flatten(byte flattening) Flattens out the valleys.
float[]	getHeightMap() getHeightMap returns the entire grid of height data.
float	getInterpolatedHeight(float x, float z) getInterpolatedHeight returns the height of a point that does not fall directly on the height posts.
float	getScaledHeightAtPoint(int x, int z) getScaledHeightAtPoint returns the scaled value at the point provided.
float[]	getScaledHeightMap() Build a new array of height data with the scaled values.
int	getSize() getSize returns the size of one side the height map.
float	getTrueHeightAtPoint(int x, int z) getTrueHeightAtPoint returns the non-scaled value at the point provided.
void	normalizeTerrain(float value) normalizeTerrain takes the current terrain data and converts it to values between 0 and value.
boolean	save(java.lang.String filename) save will save the heightmap data into a new RAW file denoted by the supplied filename.
void	setHeightAtPoint(float height, int x, int z) setHeightAtPoint sets the height value for a given coordinate.
void	setHeightScale(float scale) setHeightScale sets the scale of the height values.
void	setMagnificationFilter(float filter) setFilter sets the erosion value for the filter.
void	setSize(int size) setSize sets the size of the terrain where the area is size x size.
void	smooth(float np) Smooth the terrain.
void	smooth(float np, int radius) Smooth the terrain.
void	unloadHeightMap() unloadHeightMap clears the data of the height map.

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.jme3.terrain.heightmap.HeightMap

load

Field Detail

heightData

protected float[] heightData

Height data information.

size

protected int size

The size of the height map's width.

heightScale

protected float heightScale

Allows scaling the Y height of the map.

filter

protected float filter

The filter is used to erode the terrain.

NORMALIZE_RANGE

public static float NORMALIZE_RANGE

The range used to normalize terrain

Constructor Detail

AbstractHeightMap

public AbstractHeightMap()

Method Detail

unloadHeightMap

public void unloadHeightMap()

unloadHeightMap clears the data of the height map. This insures it is ready for reloading.

Specified by:

unloadHeightMap in interface HeightMap

setHeightScale

public void setHeightScale(float scale)

setHeightScale sets the scale of the height values. Typically, the height is a little too extreme and should be scaled to a smaller value (i.e. 0.25), to produce cleaner slopes.

Specified by:

setHeightScale in interface HeightMap

Parameters:

scale - the scale to multiply height values by.

setHeightAtPoint

public void setHeightAtPoint(float height,
                             int x,
                             int z)

setHeightAtPoint sets the height value for a given coordinate. It is recommended that the height value be within the 0 - 255 range.

Specified by:

setHeightAtPoint in interface HeightMap

Parameters:

height - the new height for the coordinate.

x - the x (east/west) coordinate.

z - the z (north/south) coordinate.

setSize

public void setSize(int size)
             throws java.lang.Exception

setSize sets the size of the terrain where the area is size x size.

Specified by:

setSize in interface HeightMap

Parameters:

size - the new size of the terrain.

Throws:

java.lang.Exception

java.lang.Exception - if the size is less than or equal to zero.

setMagnificationFilter

public void setMagnificationFilter(float filter)
                            throws java.lang.Exception

setFilter sets the erosion value for the filter. This value must be between 0 and 1, where 0.2 - 0.4 produces arguably the best results.

Specified by:

setMagnificationFilter in interface HeightMap

Parameters:

filter - the erosion value.

Throws:

java.lang.Exception - if filter is less than 0 or greater than 1.

getTrueHeightAtPoint

public float getTrueHeightAtPoint(int x,
                                  int z)

getTrueHeightAtPoint returns the non-scaled value at the point provided.

Specified by:

getTrueHeightAtPoint in interface HeightMap

Parameters:

x - the x (east/west) coordinate.

z - the z (north/south) coordinate.

Returns:

the value at (x,z).

getScaledHeightAtPoint

public float getScaledHeightAtPoint(int x,
                                    int z)

getScaledHeightAtPoint returns the scaled value at the point provided.

Specified by:

getScaledHeightAtPoint in interface HeightMap

Parameters:

x - the x (east/west) coordinate.

z - the z (north/south) coordinate.

Returns:

the scaled value at (x, z).

getInterpolatedHeight

public float getInterpolatedHeight(float x,
                                   float z)

getInterpolatedHeight returns the height of a point that does not fall directly on the height posts.

Specified by:

getInterpolatedHeight in interface HeightMap

Parameters:

x - the x coordinate of the point.

z - the y coordinate of the point.

Returns:

the interpolated height at this point.

getHeightMap

public float[] getHeightMap()

getHeightMap returns the entire grid of height data.

Specified by:

getHeightMap in interface HeightMap

Returns:

the grid of height data.

getScaledHeightMap

public float[] getScaledHeightMap()

Build a new array of height data with the scaled values.

Specified by:

getScaledHeightMap in interface HeightMap

Returns:

a new array

getSize

public int getSize()

getSize returns the size of one side the height map. Where the area of the height map is size x size.

Specified by:

getSize in interface HeightMap

Returns:

the size of a single side.

save

public boolean save(java.lang.String filename)
             throws java.lang.Exception

save will save the heightmap data into a new RAW file denoted by the supplied filename.

Parameters:

filename - the file name to save the current data as.

Returns:

true if the save was successful, false otherwise.

Throws:

java.lang.Exception - if filename is null.

normalizeTerrain

public void normalizeTerrain(float value)

normalizeTerrain takes the current terrain data and converts it to values between 0 and value.

Parameters:

value - the value to normalize to.

findMinMaxHeights

public float[] findMinMaxHeights()

Find the minimum and maximum height values.

Returns:

a float array with two value: min height, max height

erodeTerrain

public void erodeTerrain()

erodeTerrain is a convenience method that applies the FIR filter to a given height map. This simulates water erosion.

flatten

public void flatten(byte flattening)

Flattens out the valleys. The flatten algorithm makes the valleys more prominent while keeping the hills mostly intact. This effect is based on what happens when values below one are squared. The terrain will be normalized between 0 and 1 for this function to work.

Parameters:

flattening - the power of flattening applied, 1 means none

smooth

public void smooth(float np)

Smooth the terrain. For each node, its 8 neighbors heights are averaged and will participate in the node new height by a factor np between 0 and 1 You must first load() the heightmap data before this will have any effect.

Parameters:

np - The factor to what extend the neighbors average has an influence. Value of 0 will ignore neighbors (no smoothing) Value of 1 will ignore the node old height.

smooth

public void smooth(float np,
                   int radius)

Smooth the terrain. For each node, its X(determined by radius) neighbors heights are averaged and will participate in the node new height by a factor np between 0 and 1 You must first load() the heightmap data before this will have any effect.

Parameters:

np - The factor to what extend the neighbors average has an influence. Value of 0 will ignore neighbors (no smoothing) Value of 1 will ignore the node old height.