V10/libcc/outbitmap.c

#include <jstructs.h>

#define SHORTSIZE	16

#define outword(w)	((*ouch)(w) < 0 ? -1 : (*ouch)((w)>>8))
#define outpoint(p)	(outword((p).x) < 0 ? -1 : outword((p).y))
#define outrect(r)	(outpoint((r).origin) < 0 ? -1 : outpoint((r).corner))

static int ctype, count, rastwid, (*ouch)(); static short *p1;

static short *buf; static bufwid;

outbitmap(bp, r, oucharg)
Bitmap *bp; Rectangle r; int (*oucharg)();
{
	char *malloc();
	register short *pr, *q;
	register y, i;

	ouch = oucharg;
	rastwid = (r.corner.x-r.origin.x+SHORTSIZE-1)/SHORTSIZE;

	if (rastwid > bufwid) {
		if (buf)
			free(buf), bufwid = 0;
		buf = (short *)malloc(rastwid*sizeof(short));
		if (buf == 0)
			return -1;
		bufwid = rastwid;
	}

	if (outword(0) < 0 || outrect(r) < 0)
		return -1;

	pr = (short *)bp->base;
	for (i=0; i<rastwid; i++)
		buf[i] = 0;
	for (y=r.origin.y; y<r.corner.y; y++) {
		for (i=0; i<rastwid; i++)
			buf[i] ^= pr[i];
		if (outrast(buf) < 0)
			return -1;
		for (i=0; i<rastwid; i++)
			buf[i] = pr[i];
		pr = (short *)((Word *)pr + bp->width);
	}
	return 0;
}

static outrast(p2)
register short *p2;
{
	short *endraster;
	p1 = p2;
	endraster = p2+rastwid-1;
	do {
		if (p1 >= p2) {
			p2=p1+1; count=2;
			ctype=(*p1 == *p2);

		} else if ((*p2 == *(p2+1)) == ctype) {
			if (++count >= 127) {
				if (outbits() < 0)
					return -1;
				p1=p2+2;
			} else p2++;

		} else if (ctype) {
			if (outbits() < 0)
				return -1;
			p1=p2+1;
			ctype=0;

		} else {
			count--;
			if (outbits() < 0)
				return -1;
			p1=p2;
			ctype=1;
		}
	} while (p2 < endraster);

	if (p1 > endraster)
		return 0;
	if (p2 > endraster)
		count--;
	if (outbits() < 0)
		return -1;
	return 0;
}

static outbits()
{
	register c; register char *pout;
	c = count;
	if (ctype)
		c += 128, count=1;
	if ((*ouch)(c) < 0)
		return -1;
	c = sizeof(short)*count;
	pout = (char *)p1;
	while (--c >= 0)
		if ((*ouch)(*pout++) < 0)
			return -1;
	return 0;
}