/*
 * @(#)/YSliceVolumeFilter.java	1.3 96/03/31 by Andrew Barclay abb@nuccard.eushc.org
 *
 * Copyright (c) 1995 Andrew B. Barclay All Rights Reserved.
 */

import java.awt.image.ColorModel ;
import java.awt.Point ;
import java.awt.Rectangle ;

import SliceVolumeFilter ;

/**
 * An ImageFilter class for sliceing volume images.
 * This class extends the basic ImageFilter Class to extract a given
 * slice of an existing Volume and provide a source for a
 * new image containing just the extracted slice.  It is meant to
 * be used in conjunction with a FilteredImageSource object to produce
 * sliced versions of existing volumes.
 *
 * @see CropImageFilter
 * @see FilteredImageSource
 * @see ImageFilter
 * @see SliceVolumeFilter
 *
 * @version	1.1 95/12/06
 * @author 	Andrew Barclay
 */

public class YSliceVolumeFilter extends SliceVolumeFilter {
    byte outpixelsB[] ;
    int outpixelsI[] ;
    double szincr ;
    boolean debug = false ;

    /**
     * Construct a SliceVolumeFilter that extracts a slice of the source
     * Volume specified by the ul, ll and ur parameters.
     * @param srcSlices[] the array of x,y positions of the source image slices
     * @param volWidth the width of the source volume
     * @param volHeight the height of the source volume
     * @param slice the slice number to be extracted
     * @param width the width of the slice to be extracted
     * @param height the height of the slice to be extracted
     */
    public YSliceVolumeFilter( Point srcSlices[], int volWidth, int volHeight,
		double slice, int width, int height ) {
	super( srcSlices, volWidth, volHeight, slice, width, height ) ;
	type = 'Y' ;
	szincr = (double)voldims[2] / (double)height ;
    }

    /**
     * Determine if the delivered pixels intersect the slice to
     * be extracted and pass through only that subset of pixels that
     * appear in the output slice.
     */
    public void setPixels(int x, int y, int w, int h,
			  ColorModel model, byte pixels[], int off,
			  int scansize) {
	long ct = System.currentTimeMillis() ;
	Rectangle sr = new Rectangle( x, y, w, h ) ;
	int sz1 = firstZSlice( sr ) ;
	int sz2 = lastZSlice( sr ) ;
	/*
	dbg( "sr="+sr+" sz1="+sz1+" sz2="+sz2 ) ;
	dbg( "off="+off+" scansize="+scansize+" type="+type+" slice="+slice ) ;
	*/

	// implement this properly later -- for now, just take orthogonal
	// slices.
	int islice = (int)( 0.5 + slice ) ;
	if( islice >= 0 && islice < voldims[1] ) {
	    double sz = -0.5*szincr + sz1 ;
	    int ystart = (int)( 0.5 + sz/szincr ) ;
	    int iyp = 0, nlines = 0 ;
	    if( outpixelsB == null ) outpixelsB = new byte[width*height] ;
	    byte outpixels[] = outpixelsB ;

	    for( ; sz < (-0.5 + sz2) ; sz += szincr ) {
		int isz = (int)( 0.5 + sz ) ;
		int x1 = srcSlices[isz].x ;
		int y1 = srcSlices[isz].y + islice ;
		if( y <= y1 && (y+h) > y1 && x <= x1 && (x+w) > x1 ) {
		    int dx = (x1>x) ? x1-x : 0 ;
		    int dy = (y1>y) ? y1-y : 0 ;
		    int is = off + dx + dy*scansize ;
		    System.arraycopy( pixels, is, outpixels, iyp, width ) ;
		    iyp += width ;
		    nlines++ ;
		} else if( nlines == 0 ) {
		    ystart++ ;
		}
	    }

	    if( nlines > 0 ) {
		dbg( "yslice="+islice ) ;
		dbg( "sr="+sr+" sz1="+sz1+" sz2="+sz2 ) ;
		dbg( "ystart="+ystart+" nlines="+nlines ) ;

		consumer.setPixels( 0, ystart, width, nlines,
		    model, outpixels, 0, width ) ;
		dbg( "byte time= "+(System.currentTimeMillis()-ct)+" ms.\n" ) ;
	    }
	}
    }
    
    public void setPixels(int x, int y, int w, int h,
			  ColorModel model, int pixels[], int off,
			  int scansize) {
	long ct = System.currentTimeMillis() ;
	Rectangle sr = new Rectangle( x, y, w, h ) ;
	int sz1 = firstZSlice( sr ) ;
	int sz2 = lastZSlice( sr ) ;
	/*
	dbg( "sr="+sr+" sz1="+sz1+" sz2="+sz2 ) ;
	dbg( "off="+off+" scansize="+scansize+" type="+type+" slice="+slice ) ;
	*/

	// implement this properly later -- for now, just take orthogonal
	// slices.
	int islice = (int)( 0.5 + slice ) ;
	if( islice >= 0 && islice < voldims[1] ) {
	    double sz = -0.5*szincr + sz1 ;
	    int ystart = (int)( 0.5 + sz/szincr ) ;
	    int iyp = 0, nlines = 0 ;
	    if( outpixelsI == null ) outpixelsI = new int[width*height] ;
	    int outpixels[] = outpixelsI ;

	    for( ; sz < (-0.5 + sz2) ; sz += szincr ) {
		int isz = (int)( 0.5 + sz ) ;
		int x1 = srcSlices[isz].x ;
		int y1 = srcSlices[isz].y + islice ;
		if( y <= y1 && (y+h) > y1 && x <= x1 && (x+w) > x1 ) {
		    int dx = (x1>x) ? x1-x : 0 ;
		    int dy = (y1>y) ? y1-y : 0 ;
		    int is = off + dx + dy*scansize ;
		    System.arraycopy( pixels, is, outpixels, iyp, width ) ;
		    iyp += width ;
		    nlines++ ;
		} else if( nlines == 0 ) {
		    ystart++ ;
		}
	    }

	    if( nlines > 0 ) {
		dbg( "yslice="+islice ) ;
		dbg( "sr="+sr+" sz1="+sz1+" sz2="+sz2 ) ;
		dbg( "ystart="+ystart+" nlines="+nlines ) ;

		consumer.setPixels( 0, ystart, width, nlines,
		    model, outpixels, 0, width ) ;
		dbg( "int time= "+(System.currentTimeMillis()-ct)+" ms.\n" ) ;
	    }
	}
    }
    
}