#include <u.h>#include <libc.h>#include <draw.h> staticuchar*addcoord(uchar *p, int oldx, int newx){	int dx; 	dx = newx-oldx;	/* does dx fit in 7 signed bits? */	if((unsigned)(dx - -0x40) <= 0x7F)		*p++ = dx&0x7F;	else{		*p++ = 0x80 | (newx&0x7F);		*p++ = newx>>7;		*p++ = newx>>15;	}	return p;} staticvoiddopoly(int cmd, Image *dst, Point *pp, int np, int end0, int end1, int radius, Image *src, Point *sp, Drawop op){	uchar *a, *t, *u;	int i, ox, oy; 	if(np == 0)		return;	t = malloc(np*2*3);	if(t == nil)		return;	u = t;	ox = oy = 0;	for(i=0; i<np; i++){		u = addcoord(u, ox, pp[i].x);		ox = pp[i].x;		u = addcoord(u, oy, pp[i].y);		oy = pp[i].y;	} 	_setdrawop(dst->display, op); 	a = bufimage(dst->display, 1+4+2+4+4+4+4+2*4+(u-t));	if(a == 0){		free(t);		fprint(2, "image poly: %r\n");		return;	}	a[0] = cmd;	BPLONG(a+1, dst->id);	BPSHORT(a+5, np-1);	BPLONG(a+7, end0);	BPLONG(a+11, end1);	BPLONG(a+15, radius);	BPLONG(a+19, src->id);	BPLONG(a+23, sp->x);	BPLONG(a+27, sp->y);	memmove(a+31, t, u-t);	free(t);} voidpoly(Image *dst, Point *p, int np, int end0, int end1, int radius, Image *src, Point sp){	dopoly('p', dst, p, np, end0, end1, radius, src, &sp, SoverD);} voidpolyop(Image *dst, Point *p, int np, int end0, int end1, int radius, Image *src, Point sp, Drawop op){	dopoly('p', dst, p, np, end0, end1, radius, src, &sp, op);} voidfillpoly(Image *dst, Point *p, int np, int wind, Image *src, Point sp){	dopoly('P', dst, p, np, wind, 0, 0, src, &sp, SoverD);} voidfillpolyop(Image *dst, Point *p, int np, int wind, Image *src, Point sp, Drawop op){	dopoly('P', dst, p, np, wind, 0, 0, src, &sp, op);}