/*
 * #%L
 * ImgLib2: a general-purpose, multidimensional image processing library.
 * %%
 * Copyright (C) 2009 - 2016 Tobias Pietzsch, Stephan Preibisch, Stephan Saalfeld,
 * John Bogovic, Albert Cardona, Barry DeZonia, Christian Dietz, Jan Funke,
 * Aivar Grislis, Jonathan Hale, Grant Harris, Stefan Helfrich, Mark Hiner,
 * Martin Horn, Steffen Jaensch, Lee Kamentsky, Larry Lindsey, Melissa Linkert,
 * Mark Longair, Brian Northan, Nick Perry, Curtis Rueden, Johannes Schindelin,
 * Jean-Yves Tinevez and Michael Zinsmaier.
 * %%
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 * #L%
 */

package net.imglib2.display;

/**
 * 8-bit color lookup table.
 * 
 * @author Stephan Saalfeld
 * @author Curtis Rueden
 */
public class ColorTable8 extends AbstractArrayColorTable< byte[] >
{

	/** Initializes an 8-bit color table with a linear grayscale ramp. */
	public ColorTable8()
	{
		super( gray() );
	}

	/** Initializes an 8-bit color table with the given table values. */
	public ColorTable8( final byte[]... values )
	{
		super( values );
	}

	@Override
	public int getLength()
	{
		return values[ 0 ].length;
	}

	@Override
	public int getBits()
	{
		return 8;
	}

	@Override
	public int get( final int comp, final int bin )
	{
		return getNative( comp, bin );
	}

	@Override
	public int getNative( final int comp, final int bin )
	{
		return values[ comp ][ bin ] & 0xff;
	}

	@Override
	public int getResampled( final int comp, final int bins, final int bin )
	{
		final int newBin = ( int ) ( ( long ) getLength() * bin / bins );
		return getNative( comp, newBin );
	}

	// -- Helper methods --

	/** Creates a linear grayscale ramp with 3 components and 256 values. */
	private static byte[][] gray()
	{
		final byte[][] gray = new byte[ 3 ][ 256 ];
		for ( int j = 0; j < gray.length; j++ )
		{
			for ( int i = 0; i < gray[ j ].length; i++ )
			{
				gray[ j ][ i ] = ( byte ) i;
			}
		}
		return gray;
	}

}
