Light.java

package Roguelike.Lights;

import Roguelike.Global;
import Roguelike.Pathfinding.ShadowCastCache;

import com.badlogic.gdx.graphics.Color;
import com.badlogic.gdx.math.MathUtils;
import com.badlogic.gdx.utils.XmlReader.Element;

public final class Light
{
	public boolean copied;

	public Color colour;
	public float baseIntensity;
	public int flicker;
	public float flickerPeriod;

	public float actualIntensity;
	public float lx;
	public float ly;

	private float timeAccumulator;

	public ShadowCastCache shadowCastCache = new ShadowCastCache();

	public void update( float delta )
	{
		if ( flicker > 0 )
		{
			timeAccumulator += delta;
			while ( timeAccumulator > flickerPeriod )
			{
				timeAccumulator -= flickerPeriod;
			}

			float factor = 1.0f / flicker;
			float fraction = baseIntensity / 20;

			actualIntensity = fraction * 19;

			for ( int i = 0; i < flicker; i++ )
			{
				actualIntensity += fraction * (float) ( Math.sin( timeAccumulator * ( i + 1 ) / ( flickerPeriod / ( 2 * Math.PI ) ) ) * factor );
			}
		}
		else
		{
			actualIntensity = baseIntensity;
		}
	}

	public Light copyNoFlag()
	{
		Light l = copy();
		l.copied = false;
		return l;
	}

	public Light copy()
	{
		Light l = Global.LightPool.obtain();
		l.colour = new Color( colour );
		l.baseIntensity = baseIntensity;
		l.copied = true;
		l.flicker = flicker;
		l.flickerPeriod = flickerPeriod;
		l.timeAccumulator = timeAccumulator;
		l.shadowCastCache = shadowCastCache.copy();

		return l;
	}

	public static Light load( Element xml )
	{
		Light l = new Light();

		Element colourElement = xml.getChildByName( "Colour" );
		Color colour = Color.WHITE;
		if ( colourElement != null )
		{
			colour = new Color();
			colour.a = 1;

			String rgb = colourElement.get( "RGB", null );
			if ( rgb != null )
			{
				String[] cols = rgb.split( "," );
				colour.r = Float.parseFloat( cols[0] ) / 255.0f;
				colour.g = Float.parseFloat( cols[1] ) / 255.0f;
				colour.b = Float.parseFloat( cols[2] ) / 255.0f;
			}

			colour.r = colourElement.getFloat( "Red", colour.r );
			colour.g = colourElement.getFloat( "Green", colour.g );
			colour.b = colourElement.getFloat( "Blue", colour.b );
			colour.a = colourElement.getFloat( "Alpha", colour.a );

			l.colour = colour;
		}

		l.baseIntensity = xml.getFloat( "Intensity" );
		l.flicker = xml.getInt( "Flicker", 0 );
		l.flickerPeriod = xml.getFloat( "FlickerPeriod", 1 );
		l.timeAccumulator = MathUtils.random() * l.flickerPeriod;

		return l;
	}
}