org.j3d.terrain
Interface TiledTerrainData

All Superinterfaces:

HeightDataSource, TerrainData

All Known Implementing Classes:

AbstractTiledTerrainData, SimpleTiledTerrainData

public interface TiledTerrainData
extends TerrainData

Representatoin of data source that holds its data in tiles.

A tiled source is used to represent large amounts of data, that is not all held in memory at once. It may be held by the terrain data representation but the terrain renderer only access pieces by tile.

Because the terrain height is tiled, the assumption is that that the textures are tiled too. A single image is too large to handle the entire data set. The texture object will be queried for each patch that we are working with.

The implementation of this data set works on a modal-style basis. You can ask the data for tile information so that the rendering will optimise for that data access size. As part of this, it also works in an additional coordinate system - tile coordinates. Tile have their own coordinate system that describes tiles in their own X, Y system that overlays a point. Grid X and Y are still relative to the overall terrain patch, we just use tile coords to make it easier to make sure references to data areas use whole tile information and not parts of them. TerrainData.getSourceDataType() always returns TerrainData.TILED_DATA.

Version:

$Revision: 1.3 $

Author:

Justin Couch

Field Summary

Fields inherited from interface org.j3d.terrain.TerrainData

FREEFORM_DATA, STATIC_DATA, TILED_DATA

Method Summary

java.awt.image.BufferedImage	getTexture(int tileX, int tileY) Fetch the texture or part of a texture that can be applied to the sub-region of the overall object.
void	getTilesAvailableBounds(java.awt.Rectangle bounds) Fetch the area, in tile coordinates of the area that is currently available in memory.
int	getTileSize() Get the number of grid points along one side of a single tile.
void	setActiveBounds(java.awt.Rectangle bounds) Set the bounding information, in number of tiles, of the area that the terrain rendering code will be limiting its access to.

Methods inherited from interface org.j3d.terrain.TerrainData

getCoordinate, getCoordinate, getCoordinateWithColor, getCoordinateWithTexture, getGridXStep, getGridYStep, getHeightFromGrid, getSourceDataType, hasColor, hasTexture

Methods inherited from interface org.j3d.ui.navigation.HeightDataSource

getHeight

Method Detail

getTexture

java.awt.image.BufferedImage getTexture(int tileX,
                                        int tileY)

Fetch the texture or part of a texture that can be applied to the sub-region of the overall object. This is to allow for texture tiling of very large texture images or terrain items. If there is no texture or no texture for that region, then this should return null.

Parameters:

tileX - the x coordinate of the tile number for the texture

tileY - the y coordinate of the tile number for the texture

Returns:

The texture object suitable for that bounds or null

getTileSize

int getTileSize()

Get the number of grid points along one side of a single tile. Assumes a tile is square. The value should be a power of two for efficiency of the rendering algorithms.

Returns:

The number of points in the size if the grid

getTilesAvailableBounds

void getTilesAvailableBounds(java.awt.Rectangle bounds)

Fetch the area, in tile coordinates of the area that is currently available in memory. This is a hint to the caller that it would be a good strategy to start with these tiles for fastest load time.

The implementation should fill in the passed rectangle with the bounds information. The bounds are inclusive, so if the implementation of this interface provides the value of {0, 0, 2, 2} this will indicate a 3x3 area is available.

Parameters:

bounds - The bounds of the available data, to be filled in by the implementation of this class

setActiveBounds

void setActiveBounds(java.awt.Rectangle bounds)

Set the bounding information, in number of tiles, of the area that the terrain rendering code will be limiting its access to. This is a directive by the terrain rendering code that it will be using all the tiles contained within this boarder area within the next frame so the implementation class should start to load that data now. The implementation is free to load more than this aree into memory if it feels like it.

The values passes are inclusive tile values. A bounds of {0, 0, 1, 1} would be a 2x2 set of tiles.

Parameters:

bounds - The bounds of the area, in tile coordinates, that will be accessed