wyvern.lib.properties
Interface LightSource

All Known Implementing Classes:

SimpleLightSource

public interface LightSource

This interface encapsulates much of the functionality of the game's lighting model. Light sources in the game are independent objects that "attach" to game objects to make them luminous.

Version:

1.0, Feb 06, 1999

Author:

Steve Yegge

Method Summary

int[][]	getLightMatrix() Returns the location list for the light source.
Point	getMatrixLocation() Returns the (x,y) location of the upper-left corner of the LightSource's local light matrix returned by calling getLightMatrix().
void	recompute() Tells the light source to recompute its intensity matrix.
void	remove() Removes this light from its current map, if any.
void	setMap(GameMap map, int x, int y) Tells the light which map to illuminate.

Method Detail

getLightMatrix

public int[][] getLightMatrix()

Returns the location list for the light source. The light is typically centered in the array, although that's not required, nor are there any constraints on the array dimensions (e.g. it can be even by odd). The map will take the array and "apply" it into the global array at the (x,y) location returned by getMatrixLocation().

Returns:

the local array of integer intensities computed by the LightSource. Each array value is added to (or subtracted from, in the case where the LightSource is removed) the map. An array value of zero thus has no effect, and LightSource implementations can make use of this to return custom-shaped illumination patterns.

getMatrixLocation

public Point getMatrixLocation()

Returns the (x,y) location of the upper-left corner of the LightSource's local light matrix returned by calling getLightMatrix().

Returns:

the point in the map at which to apply the local array. The LightSource has to know where it is in the map anyway, so that it can call addLight() at the appropriate location, not to mention compute its intensity array correctly using the ray-caster utilities. Since the LightSource is in complete control of where its light is displayed, it has to tell the map where to apply its local intensity array; hence this method.

recompute

public void recompute()

Tells the light source to recompute its intensity matrix. A square in the map has changed opacity, or some other event has occurred that would cause the light's intensity matrix to be invalid.

setMap

public void setMap(GameMap map,
                   int x,
                   int y)

Tells the light which map to illuminate. This method causes the light to call recompute(), which figures out its lighting contribution and adds that contribution to the passed map.

Parameters:

map - the map to put the light in

x - map x location

y - map y location

remove

public void remove()

Removes this light from its current map, if any.