MapAPI 1.3

Class: IWProjection

IWProjection

An interface which has to be implemented by all map projections. A projection is used by the map to convert from pixel space to map coordinates and vice versa.

new IWProjection()

Default constructor.

Methods

calculateGridOffset(map)

Calculates the offset of the point (0, 0) to a position on the tile grid.
Parameters:
Name Type Description
map IWMap a map
Returns:
the offset
Type
IWPoint

clone()

Returns a copy of this projection.

generateTileInformation(x, y, gridOffset)

Generates information like the tile screen position, tile index and tile id for a pixel position.
Parameters:
Name Type Description
x number screen position of the tile
y number screen position of the tile
gridOffset IWPoint offset of (0, 0) to the tile grid
Returns:
Type
object

initialize(xmlDocument)

Initializes the projection parameters from a XML document.
Parameters:
Name Type Description
xmlDocument Document a XML document storing all parameters used by the current projection
Returns:
Type
void

meterToPixel(coord)

Returns the offset in pixels of the specified coordinate to the map center.
Parameters:
Name Type Description
coord IWCoordinate a coordinate
Returns:
Type
IWPoint

needsReload(size)

Checks whether the map has to be reloaded completely to display the specified region.
Parameters:
Name Type Description
size IWSize the size of the visible part of the map in pixels
Returns:
Type
boolean

pixelToMeter(offset)

Returns the coordinate of the current map center plus the specified offset in pixels.
Parameters:
Name Type Description
offset IWPoint an offset
Returns:
Type
IWCoordinate

toString()

Returns a text representation of this projection.
Returns:
Type
String