pslib.c

这是一个同样来自贝尔实验室的和UNIX有着渊源的操作系统, 其简洁的设计和实现易于我们学习和理解

/* 		bits=1<<bits;
/* 	else{
/* 		bits=1;
/* 		def_font_type=bits;
/* 		curfonttype=def_font_type;
/* 	}
/* 	font=font[2:];
/* 	for(i:=0;i<len remap;i++){
/* 		(tkfont,psfont)=remap[i];
/* 		if (tkfont==font)
/* 			break;
/* 	}
/* 	if (i==len remap)
/* 		psfont="Times-Roman";
/* 	(font,nil)=str->splitr(font,".");
/* 	(nil,font)=str->splitr(font[0:len font-1],".");
/* 	(fsize,nil):=str->toint(font,10);
/* 	fsize=(PTPI*3*fsize)/(2*PXPI);
/* 	enc_font:="f"+string bits+"."+string fsize;
/* 	ps_func:="/"+enc_font+" /"+psfont+" findfont "+string fsize+
/* 							" scalefont def\n";
/* 	sy_font:="sy"+string fsize;
/* 	xtra_func:="/"+sy_font+" /Symbol findfont "+string fsize+
/* 							" scalefont def\n";
/* 	for(i=0;i<len font_arr;i++){
/* 		(j,font)=font_arr[i];
/* 		if (j==-1) break;
/* 	}
/* 	if (j==len font_arr)
/* 		return "Error";
/* 	font_arr[i]=(bits,enc_font);
/* 	if (bits==1)
/* 		def_font=enc_font;
/* 	curfont++;
/* 	retval+= ps_func;
/* 	retval+= xtra_func;	
/* 	return retval;
/* }
/* 
/* deffont() : string
/* {
/* 	return def_font;
/* }
/* 	
/* getline(k : int,  input : string) : (array of iteminfo, string)
/* {
/* 	lineval,args : string;
/* 	j, nb : int;
/* 	lw:=0;
/* 	wid:=0;
/* 	flags:=0;
/* 	item_arr := array[32] of {* => iteminfo(-1,-1,-1,-1,-1,-1,"")};
/* 	curitem:=0;
/* 	while(input!=nil){
/* 		(nil,input)=str->splitl(input,"[");
/* 		if (input==nil)
/* 			break;
/* 		com:=input[1];
/* 		input=input[2:];
/* 		case com {
/* 			'A' =>
/* 				nb=0;
/* 				# get the width of the item
/* 				(wid,input)=str->toint(input,10);
/* 				wid=(wid*PTPI)/PXPI;
/* 				if (input[0]!='{')
/* 					return (nil, sys->sprint(
/* 						"line %d item %d Bad Syntax : '{' expected",
/* 							k,curitem));
/* 				# get the args.
/* 				(args,input)=str->splitl(input,"}");
/* 				# get the flags.
/* 				# assume there is only one int flag..
/* 				(flags,args)=str->toint(args[1:],16);
/* 				if (args!=nil && debug){
/* 					sys->print("line %d item %d extra flags=%s\n",
/* 							k,curitem,args);
/* 				}
/* 				if (flags<1024) flags=1;
/* 				item_arr[curitem].font=flags;
/* 				item_arr[curitem].offset=lw;
/* 				item_arr[curitem].width=wid;
/* 				lw+=wid;
/* 				for(j=1;j<len input;j++){
/* 					if ((input[j]==')')||(input[j]=='('))
/* 							lineval[len lineval]='\\';
/* 					if (input[j]=='[')
/* 						nb++;
/* 					if (input[j]==']')
/* 						if (nb==0)
/* 							break;
/* 						else 
/* 							nb--;
/* 					lineval[len lineval]=input[j];
/* 				}
/* 				if (j<len input)
/* 					input=input[j:];
/* 				item_arr[curitem].buf=lineval;
/* 				item_arr[curitem].line=k;
/* 				item_arr[curitem].itype=ASCII;
/* 				curitem++;
/* 				lineval="";
/* 			'R' =>
/* 				nb=0;
/* 				# get the width of the item
/* 				(wid,input)=str->toint(input,10);
/* 				wid=(wid*PTPI)/PXPI;
/* 				if (input[0]!='{')
/* 					return (nil, "Bad Syntax : '{' expected");
/* 				# get the args.
/* 				(args,input)=str->splitl(input,"}");
/* 				# get the flags.
/* 				# assume there is only one int flag..
/* 				(flags,args)=str->toint(args[1:],16);
/* 				if (args!=nil && debug){
/* 					sys->print("line %d item %d Bad Syntax args=%s",
/* 							k,curitem,args);
/* 				}
/* 				item_arr[curitem].font=flags;
/* 				item_arr[curitem].offset=lw;
/* 				item_arr[curitem].width=wid;
/* 				lw+=wid;
/* 				for(j=1;j<len input;j++){
/* 					if (input[j]=='[')
/* 						nb++;
/* 					if (input[j]==']')
/* 						if (nb==0)
/* 							break;
/* 						else 
/* 							nb--;
/* 					case input[j] {
/* 						8226 => # bullet
/* 							lineval+="\\267 ";
/* 						169 =>  # copyright
/* 							lineval+="\\251 ";
/* 							curitem++;			
/* 						* =>
/* 							lineval[len lineval]=input[j];
/* 					}
/* 				}
/* 				if (j>len input)
/* 					input=input[j:];
/* 				item_arr[curitem].buf=lineval;
/* 				item_arr[curitem].line=k;
/* 				item_arr[curitem].itype=RUNE;
/* 				curitem++;
/* 				lineval="";
/* 			'N' or 'C'=>
/* 				# next item
/* 				for(j=0;j<len input;j++)
/* 					if (input[j]==']')
/* 						break;
/* 				if (j>len input)
/* 					input=input[j:];
/* 			'T' =>
/* 				(wid,input)=str->toint(input,10);
/* 				wid=(wid*PTPI)/PXPI;
/* 				item_arr[curitem].offset=lw;
/* 				item_arr[curitem].width=wid;
/* 				lw+=wid;
/* 				lineval[len lineval]='\t';
/* 				# next item
/* 				for(j=0;j<len input;j++)
/* 					if (input[j]==']')
/* 						break;
/* 				if (j>len input)
/* 					input=input[j:];
/* 				item_arr[curitem].buf=lineval;
/* 				item_arr[curitem].line=k;
/* 				item_arr[curitem].itype=ASCII;
/* 				curitem++;
/* 				lineval="";
/* 			'W' =>
/* 				(wid,input)=str->toint(input,10);
/* 				wid=(wid*PTPI)/PXPI;
/* 				item_arr[curitem].offset=lw;
/* 				item_arr[curitem].width=wid;
/* 				item_arr[curitem].itype=IMAGE;
/* 				lw+=wid;
/* 				# next item
/* 				for(j=1;j<len input;j++){
/* 					if (input[j]==']')
/* 						break;
/* 					lineval[len lineval]=input[j];
/* 				}
/* 				item_arr[curitem].buf=lineval;
/* 				if (j>len input)
/* 					input=input[j:];
/* 				curitem++;
/* 				lineval="";
/* 			* =>
/* 				# next item
/* 				for(j=0;j<len input;j++)
/* 					if (input[j]==']')
/* 						break;
/* 				if (j>len input)
/* 					input=input[j:];
/* 				
/* 		}
/* 	}
/* 	return (item_arr[0:curitem], "");	
/* }
*/

void
cmap2ascii85(uchar *b, uchar *c) {
	int i;
	unsigned long i1;

/*	fprintf(stderr, "addr=0x%x %x %x %x %x\n", b, b[0], b[1], b[2], b[3]); */
	b--;	/* one-index b */
	c--;	/* one-index c */
	i1 = (b[1]<<24)+(b[2]<<16)+(b[3]<<8)+b[4];
	if(i1 == 0){
		c[1] = 'z';
		c[2] = '\0';
		return;
	}
	for(i=0; i<=4; i++){
		c[5-i] = '!' + (i1 % 85);
		i1 /= 85;
	}
	c[6] = '\0';
}

static uchar *arr = nil;
ulong	onesbits = ~0;
void
imagebits(Biobuf *ioutb, Memimage *im)
{
	int spb;
	int bitoff;
	int j, n, n4, i, bpl, nrest;
	int lsf;
	uchar c85[6], *data, *src, *dst;
	Memimage *tmp;
	Rectangle r;

	tmp = nil;
	if (debug)
		fprint(2, "imagebits, r=%d %d %d %d, depth=%d\n",
			im->r.min.x, im->r.min.y, im->r.max.x, im->r.max.y, im->depth);
	width = Dx(im->r);
	height = Dy(im->r);
	bps = im->depth;	/* # bits per sample */
	bitoff = 0;		/* # bit offset of beginning sample within first byte */
	if (bps < 8) {
		spb = 8 / bps;
		bitoff = (im->r.min.x % spb) * bps;
	}
	if (bitoff != 0) {
/* 		# Postscript image wants beginning of line at beginning of byte */
		r = im->r;
		r.min.x -= bitoff/im->depth;
		r.max.x -= bitoff/im->depth;
		tmp = allocmemimage(r, im->chan);
		if(tmp == nil){
			fprint(2, "p9bitpost: allocmemimage failed: %r\n");
			exits("alloc");
		}
		memimagedraw(tmp, r, im, im->r.min, nil, ZP, S);
		im = tmp;
	}
	lsf = 0;
	/* compact data to remove word-boundary padding */
	bpl = bytesperline(im->r, im->depth);
	n = bpl*Dy(im->r);
	data = malloc(n);
	if(data == nil){
		fprint(2, "p9bitpost: malloc failed: %r\n");
		exits("malloc");
	}
	for(i=0; i<Dy(im->r); i++){
		/* memmove(data+bpl*i, byteaddr(im, Pt(im->r.min.x, im->r.min.y+i)), bpl); with inversion */
		dst = data+bpl*i;
		src = byteaddr(im, Pt(im->r.min.x, im->r.min.y+i));
		for(j=0; j<bpl; j++)
			*dst++ = 255 - *src++;
	}
	n4 = (n / 4) * 4;
	for (i = 0; i < n4; i += 4){
		cmap2ascii85(data+i, c85);
		lsf += strlen((char *)c85);
		Bprint(ioutb, "%s", c85);
		if (lsf > 74) {
			Bprint(ioutb, "\n");
			lsf = 0;
		}
	}
	nrest = n - n4;
	if (nrest != 0) {
		uchar foo[4];

		for (i=0; i<nrest; i++)
			foo[i] = data[n4+i];
		for (i=nrest; i<4; i++)
			foo[i] = '\0';
		cmap2ascii85(foo, c85);
		if (strcmp((char *)c85, "z") == 0 )
			strcpy((char *)c85, "!!!!!");
		Bprint(ioutb, "%.*s", nrest+1, c85);
	}
	Bprint(ioutb, "\n~>");
	Bprint(ioutb, "\n");
	freememimage(tmp);
}

int
image2psfile(int fd, Memimage *im, int dpi) {
	Rectangle r;
	Rectangle bbox;
	int e;
	int xmargin = 36;
	int ymargin = 36;
	double paperaspectratio;
	double imageaspectratio;
	Biobuf ioutb;
	Memimage *tmp;

	if(im->depth >= 8 && im->chan != CMAP8 && im->chan != GREY8){
		/*
		 * the postscript libraries can only handle [1248]-bit grey, 8-bit cmap,
		 * and 24-bit color, so convert.
		 */
		tmp = allocmemimage(im->r, strtochan("b8g8r8"));
		if(tmp == nil)
			return 1;
		memimagedraw(tmp, tmp->r, im, im->r.min, nil, ZP, S);
		freememimage(im);
		im = tmp;
	}

	Binit(&ioutb, fd, OWRITE);
 	r = im->r;
	width = Dx(r);
	height = Dy(r);
	imageaspectratio = (double) width / (double) height;
	if (landscape) {
		paperaspectratio = ((double)paperlength - (ymargin * 2)) / ((double)paperwidth - (xmargin * 2));
		if (dpi > 0) {
			iwidth = width * 72 / dpi;
			iheight = height * 72 / dpi;
		} else if (imageaspectratio > paperaspectratio) {
			iwidth = paperlength - (ymargin * 2);
			iheight = iwidth / imageaspectratio;
		} else {
			iheight = paperwidth - (xmargin * 2);
			iwidth  = iheight * imageaspectratio;
		}
		xstart = paperwidth - xmargin - (iheight * ymagnification);
		ystart = paperlength - ymargin;
		rotation = -90;
	} else {
		paperaspectratio = ((double)paperwidth - (xmargin * 2)) / ((double)paperlength - (ymargin * 2));
		if (dpi > 0) {
			iwidth = width * 72 / dpi;
			iheight = height * 72 / dpi;
		} else if (imageaspectratio > paperaspectratio) {
			iwidth = paperwidth - (xmargin * 2);
			iheight = iwidth / imageaspectratio;
		} else {
			iheight = paperlength - (ymargin * 2);
			iwidth  = iheight * imageaspectratio;
		}
		xstart = xmargin;
		ystart = paperlength - ymargin - (iheight * ymagnification);
		rotation = 0;
	}
	bbox = Rect(xstart,ystart,xstart+iwidth,ystart+iheight);
	e = preamble(&ioutb, bbox);
	if(e != 0)
		return e;
	Bprint(&ioutb, "%%%%Page: 1\n%%%%BeginPageSetup\n");
	Bprint(&ioutb, "/pgsave save def\n");
	Bprint(&ioutb, "%%%%EndPageSetup\n");
	bps = im->depth;
	Bprint(&ioutb, "%d 0 %d %d %d %d %d %d %s doimage\n", iheight, iwidth, ystart, xstart, height, width, bps, im->flags&Fgrey ? "true" : "false");
 	imagebits(&ioutb, im);
	Bprint(&ioutb, "pgsave restore\nshowpage\n");
	e = trailer(&ioutb, 1);
	if(e != 0)
		return e;
	Bterm(&ioutb);
	return 0;
}

/* set local variables by string and pointer to its value
 * the variables are:
 *   int magnification
 *   int landscape
 *   char *Patch
 */
void
psopt(char *s, void *val)
{
	if(s == nil)
		return;
	if(strcmp("xmagnification", s) == 0)
		xmagnification = *((double *)val);
	if(strcmp("ymagnification", s) == 0)
		ymagnification = *((double *)val);
	if(strcmp("landscape", s) == 0)
		landscape = *((int *)val);
	if(strcmp("Patch", s) == 0)
		Patch = *((char **)val);
}