ilog.views.maps.defense.terrain3d.model

Class Ilv3DTile

java.lang.Object

ilog.views.maps.defense.terrain3d.model.Ilv3DTile

Direct Known Subclasses:

IlvRasterMappedBuffer3DTile

public abstract class Ilv3DTile
extends Object

This class is a 3D mesh object capable of displaying elevation data at different sampling levels, according to its relative position from the viewing point. Geometry as well as texture downsampling are done dynamically at rendering time. It is backed by a IlvTileElevationProvider that provides elevation values to build the terrain mesh. Three abstract methods must be implemented in a concrete subclass : - loadDem(), which is responsible for setting up the elevation provider on this tile. This must be called once by the user after tile creation. - drawImageData(..), which is responsible for setting up the OpenGL texture that is used to draw the terrain. - loadImg(..), which is responsible for actually generating the image used as a texture given the current tile subsampling level. This method is dynamically called by the rendering loop as the camera gets closer or farther from the terrain

Since:

JViews 7.5

Constructor Summary

Constructors

Constructor and Description
Ilv3DTile(int minDEMHeight) Constructs an Ilv3DTile.

Method Summary

Modifier and Type	Method and Description
abstract void	drawImageData(GL2 gl, int width, int height) Method responsible for setting up the OpenGL texture that is used to draw the terrain.
void	drawTile(int filletMask, Ilv3DLinearCoordinateConverter coordConverter, IlvBufferSliceManager geomBuf, Ilv3DCamera camera, GL2 gl, boolean isBilinearFiltering) Renders the tile in the specified OpenGL context at the current DEM and image level.
void	drawTile(int filletMask, Ilv3DLinearCoordinateConverter coordConverter, IlvBufferSliceManager geomBuf, Ilv3DCamera camera, GL2 gl, Ilv3DView view, boolean isBilinearFiltering) Renders the tile in the specified OpenGL context at the current DEM and image level.
float[]	getApparentAreaFactors() Returns the apparent areas at different levels.
Ilv3DDoubleVector	getCenter() Return the center point of this tile, in 3D space coordinates
double	getGroundHeightAt(double x, double z) Computes and returns the elevation (above ground) at the specified location in 3D space coordinates.
int	getTextureHeight() Returns the height of the texture applied to this tile.
int	getTextureWidth() Returns the width of the texture applied to this tile.
IlvTileElevationProvider	getTileElevationProvider() Returns the associated IlvTileElevationProvider used by this tile to fetch elevation values when building the terrain mesh.
float	getTileHeight() Return the height of this tile (in 3D space coordinates)
float	getTileWidth() Return the width of this tile (in 3D space coordinates)
boolean	isKeepElevationDataCache() Returns whether the tile should keep a copy of downsampled elevation data (depending on the camera position), or rather compute it at rendering time.
abstract void	loadDEM() Method responsible for loading and setting up the underlying IlvTileElevationProvider.
abstract void	loadImg(int imageLevel, IlvThreadedTaskProcessor.ThreadedTask task) This method is responsible for generating the texture for the specified image level.
void	regenerateTexture() Forces a texture map generation at the next display.
protected void	setImageSize(int width, int height) Sets the size of the texture as created by the drawImageData method.
void	setKeepElevationDataCache(boolean keepElevationDataCache) Sets whether the tile should keep a copy of downsampled elevation data (depending on the camera position), or rather compute it at rendering time.
protected void	setSize(Ilv3DDoubleVector center, float tileWidth, float tileHeight) Sets the bounds of this Ilv3DTile
void	setTextureHeight(int textureHeight) Sets the height of the texture applied to this tile.
void	setTextureWidth(int textureWidth) Sets the width of the texture applied to this tile.
protected void	setTileElevationProvider(IlvTileElevationProvider provider) Sets the associated IlvTileElevationProvider used by this tile to fetch elevation values when building the terrain mesh.
void	setupDEMLevel(int demLevel) Sets the downsampling factor for the geometry of this tile.
void	setupImgLevel(int imageLevel, Ilv3DView view) Sets the downsampling factor for the texture of this tile.

Methods inherited from class java.lang.Object

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

Constructor Detail

Ilv3DTile

public Ilv3DTile(int minDEMHeight)

Constructs an Ilv3DTile.

Parameters:

minDEMHeight - The minimum accepted value for elevation values. Any value below this one will be raised to this one.

Method Detail

getTileWidth

public float getTileWidth()

Return the width of this tile (in 3D space coordinates)

Returns:

The tile width.

getTileHeight

public float getTileHeight()

Return the height of this tile (in 3D space coordinates)

Returns:

The tile height.

getCenter

public Ilv3DDoubleVector getCenter()

Return the center point of this tile, in 3D space coordinates

Returns:

The center of the tile.

Since:

JViews 8.1

regenerateTexture

public void regenerateTexture()

Forces a texture map generation at the next display. This is needed, for instance, to reflect the change in the 3D view when new layers are added to the map.

getApparentAreaFactors

public float[] getApparentAreaFactors()

Returns the apparent areas at different levels.

Returns:

The apparent areas.

Internal: do not use!

getGroundHeightAt

public double getGroundHeightAt(double x,
                                double z)

Computes and returns the elevation (above ground) at the specified location in 3D space coordinates. If the point lies outside the bounds of the tile, NaN is returned.

Parameters:

x - The X coordinate of the point, in 3D model space.

z - The Z coordinate of the point, in 3D model space.

Returns:

The terrain elevation at specified location, or Double.NaN if outside the bounds of the tile.

setupDEMLevel

public void setupDEMLevel(int demLevel)

Sets the downsampling factor for the geometry of this tile. A level of n means that only one point out of 2 exp(n) is used to build the terrain mesh. This method is dynamically called by the rendering loop to adjust the precision level according to the camera position.

Parameters:

demLevel - The downsampling factor.

drawTile

public void drawTile(int filletMask,
                     Ilv3DLinearCoordinateConverter coordConverter,
                     IlvBufferSliceManager geomBuf,
                     Ilv3DCamera camera,
                     GL2 gl,
                     boolean isBilinearFiltering)

Renders the tile in the specified OpenGL context at the current DEM and image level.

Parameters:

filletMask - A flag specifying the fillets that should be drawn for this tile (north,south, east,west).

coordConverter - The current Ilv3DCoordinateConverter of the view.

geomBuf - A BufferSliceManager that manages buffer slices used by this tile for rendering.

camera - The Ilv3DCamera object through which this tile is viewed.

gl - The OpenGL context to render into.

isBilinearFiltering - A boolean specifying that rendering should use bilinear filtering of textures.

Since:

JViews 8.1

drawTile

public void drawTile(int filletMask,
                     Ilv3DLinearCoordinateConverter coordConverter,
                     IlvBufferSliceManager geomBuf,
                     Ilv3DCamera camera,
                     GL2 gl,
                     Ilv3DView view,
                     boolean isBilinearFiltering)

Renders the tile in the specified OpenGL context at the current DEM and image level.

Parameters:

filletMask - A flag specifying the fillets that should be drawn for this tile (north,south, east,west).

coordConverter - The current Ilv3DCoordinateConverter of the view.

geomBuf - ABufferSliceManager that manages buffer slices used by this tile for rendering.

camera - The Ilv3DCamera object through which this tile is viewed.

gl - The OpenGL context to render into.

view - The Ilv3DView where this tile is being drawn.

isBilinearFiltering - A boolean specifying that rendering should use bilinear filtering of textures.

Since:

JViews 8.1

loadDEM

public abstract void loadDEM()
                      throws IOException

Method responsible for loading and setting up the underlying IlvTileElevationProvider.

Throws:

IOException - if loading encounters an exception

drawImageData

public abstract void drawImageData(GL2 gl,
                                   int width,
                                   int height)

Method responsible for setting up the OpenGL texture that is used to draw the terrain. Use the image generated in the loadImg() method.

Parameters:

gl - The OpenGL context to set the texture onto.

width - The width of the texture image.

height - The height of the texture image.

setupImgLevel

public void setupImgLevel(int imageLevel,
                          Ilv3DView view)

Sets the downsampling factor for the texture of this tile. A level of n means that only one point out of 2 exp(n) is used to build generate the texture. This method is dynamically called by the rendering loop to adjust the precision level according to the camera position. It loads the image at the specified level in a separate thread.

Parameters:

imageLevel - The downsampling factor.

view - The Ilv3DView to be refreshed when the asynchronous image loading is finished.

setImageSize

protected void setImageSize(int width,
                            int height)

Sets the size of the texture as created by the drawImageData method.

Parameters:

width - The texture width.

height - The texture height.

loadImg

public abstract void loadImg(int imageLevel,
                             IlvThreadedTaskProcessor.ThreadedTask task)
                      throws IOException

This method is responsible for generating the texture for the specified image level. It is called from a dedicated loading thread, so that any intensive code will not block OpenGL drawing. Implementing a subclass will generate and store this image, which will be used to setup the texture in drawImageData() method.

Parameters:

imageLevel - The downsampling level for image to generate.

task - The threaded task that is calling this method.

Throws:

IOException - if an exception is thrown when generating the image.

setTileElevationProvider

protected void setTileElevationProvider(IlvTileElevationProvider provider)

Sets the associated IlvTileElevationProvider used by this tile to fetch elevation values when building the terrain mesh.

Parameters:

provider - The IlvTileElevationProvider this tile is based upon.

getTileElevationProvider

public IlvTileElevationProvider getTileElevationProvider()

Returns the associated IlvTileElevationProvider used by this tile to fetch elevation values when building the terrain mesh.

Returns:

provider The IlvTileElevationProvider this tile is based upon.

setSize

protected void setSize(Ilv3DDoubleVector center,
                       float tileWidth,
                       float tileHeight)

Sets the bounds of this Ilv3DTile

Parameters:

center - The center of this tile.

tileWidth - This tile's width, in 3D space coordinates.

tileHeight - This tile's height, in 3D space coordinates.

Since:

JViews 8.1

isKeepElevationDataCache

public boolean isKeepElevationDataCache()

Returns whether the tile should keep a copy of downsampled elevation data (depending on the camera position), or rather compute it at rendering time. If true, the higher the frame rate of the view, but also the bigger the memory usage (as part of the elevation data is duplicated).

Returns:

true if the tile caches its elevation data.

setKeepElevationDataCache

public void setKeepElevationDataCache(boolean keepElevationDataCache)

Sets whether the tile should keep a copy of downsampled elevation data (depending on the camera position), or rather compute it at rendering time. If true, the higher the frame rate of the view, but also the bigger the memory usage (as part of the elevation data is duplicated).

Parameters:

keepElevationDataCache - true if the tile caches its elevation data.

getTextureHeight

public int getTextureHeight()

Returns the height of the texture applied to this tile.

Returns:

The texture height.

Since:

JViews 8.0

setTextureHeight

public void setTextureHeight(int textureHeight)

Sets the height of the texture applied to this tile.

Parameters:

textureHeight - The texture height.

Since:

JViews 8.0

getTextureWidth

public int getTextureWidth()

Returns the width of the texture applied to this tile.

Returns:

The texture width.

Since:

JViews 8.0

setTextureWidth

public void setTextureWidth(int textureWidth)

Sets the width of the texture applied to this tile.

Parameters:

textureWidth - The texture width.

Since:

JViews 8.0