diff --git a/src/cmd/plot/libplot/fill.c b/src/cmd/plot/libplot/fill.c
new file mode 100644
index 0000000..a33294e
--- /dev/null
+++ b/src/cmd/plot/libplot/fill.c
@@ -0,0 +1,167 @@
+/*
+ * fill -- polygon tiler
+ * Updating the edgelist from scanline to scanline could be quicker if no
+ * edges cross:  we can just merge the incoming edges.  If the scan-line
+ * filling routine were a parameter, we could do textured
+ * polygons, polyblt, and other such stuff.
+ */
+#include "mplot.h"
+typedef enum{
+	Odd=1,
+	Nonzero=~0
+}Windrule;
+typedef struct edge Edge;
+struct edge{
+	Point p;	/* point of crossing current scan-line */
+	int maxy;	/* scan line at which to discard edge */
+	int dx;		/* x increment if x fraction<1 */
+	int dx1;	/* x increment if x fraction>=1 */
+	int x;		/* x fraction, scaled by den */
+	int num;	/* x fraction increment for unit y change, scaled by den */
+	int den;	/* x fraction increment for unit x change, scaled by num */
+	int dwind;	/* increment of winding number on passing this edge */
+	Edge *next;	/* next edge on current scanline */
+	Edge *prev;	/* previous edge on current scanline */
+};
+static void insert(Edge *ep, Edge **yp){
+	while(*yp && (*yp)->p.x<ep->p.x) yp=&(*yp)->next;
+	ep->next=*yp;
+	*yp=ep;
+	if(ep->next){
+		ep->prev=ep->next->prev;
+		ep->next->prev=ep;
+		if(ep->prev)
+			ep->prev->next=ep;
+	}
+	else
+		ep->prev=0;
+}
+static void polygon(int cnt[], double *pts[], Windrule w, int v){
+	Edge *edges, *ep, *nextep, **ylist, **eylist, **yp;
+	Point p, q, p0, p1, p10;
+	int i, dy, nbig, y, left, right, wind, nwind, nvert;
+	int *cntp;
+	double **ptsp, *xp;
+	nvert=0;
+	for(cntp=cnt;*cntp;cntp++) nvert+=*cntp;
+	edges=(Edge *)malloc(nvert*sizeof(Edge));
+	if(edges==0){
+	NoSpace:
+		fprintf(stderr, "polygon: no space\n");
+		exits("malloc failed");
+	}
+	ylist=(Edge **)malloc(Dy(screen->r)*sizeof(Edge *));
+	if(ylist==0) goto NoSpace;
+	eylist=ylist+Dy(screen->r);
+	for(yp=ylist;yp!=eylist;yp++) *yp=0;
+	ep=edges;
+	for(cntp=cnt,ptsp=pts;*cntp;cntp++,ptsp++){
+		p.x=SCX((*ptsp)[*cntp*2-2]);
+		p.y=SCY((*ptsp)[*cntp*2-1]);
+		nvert=*cntp;
+		for(xp=*ptsp,i=0;i!=nvert;xp+=2,i++){
+			q=p;
+			p.x=SCX(xp[0]);
+			p.y=SCY(xp[1]);
+			if(p.y==q.y) continue;
+			if(p.y<q.y){
+				p0=p;
+				p1=q;
+				ep->dwind=1;
+			}
+			else{
+				p0=q;
+				p1=p;
+				ep->dwind=-1;
+			}
+			if(p1.y<=screen->r.min.y) continue;
+			if(p0.y>=screen->r.max.y) continue;
+			ep->p=p0;
+			if(p1.y>screen->r.max.y)
+				ep->maxy=screen->r.max.y;
+			else
+				ep->maxy=p1.y;
+			p10=subpt(p1, p0);
+			if(p10.x>=0){
+				ep->dx=p10.x/p10.y;
+				ep->dx1=ep->dx+1;
+			}
+			else{
+				p10.x=-p10.x;
+				ep->dx=-(p10.x/p10.y); /* this nonsense rounds toward zero */
+				ep->dx1=ep->dx-1;
+			}
+			ep->x=0;
+			ep->num=p10.x%p10.y;
+			ep->den=p10.y;
+			if(ep->p.y<screen->r.min.y){
+				dy=screen->r.min.y-ep->p.y;
+				ep->x+=dy*ep->num;
+				nbig=ep->x/ep->den;
+				ep->p.x+=ep->dx1*nbig+ep->dx*(dy-nbig);
+				ep->x%=ep->den;
+				ep->p.y=screen->r.min.y;
+			}
+			insert(ep, ylist+(ep->p.y-screen->r.min.y));
+			ep++;
+		}
+	}
+	left = 0;
+	for(yp=ylist,y=screen->r.min.y;yp!=eylist;yp++,y++){
+		wind=0;
+		for(ep=*yp;ep;ep=nextep){
+			nwind=wind+ep->dwind;
+			if(nwind&w){	/* inside */
+				if(!(wind&w)){
+					left=ep->p.x;
+					if(left<screen->r.min.x) left=screen->r.min.x;
+				}
+			}
+			else if(wind&w){
+				right=ep->p.x;
+				if(right>=screen->r.max.x) right=screen->r.max.x;
+#define BART_BUG_FIXED	/* what goes on here?? -rob */
+#ifdef BART_BUG_FIXED
+				if(right>left)
+					line(screen, Pt(left, y), Pt(right, y), Endsquare, Endsquare, 0, getcolor(v), ZP);
+#else
+				if(right>left){
+					switch(v){
+					default:
+						segment(&screen, Pt(left, y), Pt(right, y),
+							~0, D&~S);
+						segment(&screen, Pt(left, y), Pt(right, y),
+							v, f);
+						break;
+					case 0:
+						segment(&screen, Pt(left, y), Pt(right, y),
+							~0, D&~S);
+						break;
+					case 3:
+						segment(&screen, Pt(left, y), Pt(right, y),
+							v, f);
+						break;
+					}
+				}
+#endif
+			}
+			wind=nwind;
+			nextep=ep->next;
+			if(++ep->p.y!=ep->maxy){
+				ep->x+=ep->num;
+				if(ep->x>=ep->den){
+					ep->x-=ep->den;
+					ep->p.x+=ep->dx1;
+				}
+				else
+					ep->p.x+=ep->dx;
+				insert(ep, yp+1);
+			}
+		}
+	}
+	free((char *)edges);
+	free((char *)ylist);
+}
+void fill(int num[], double *ff[]){
+	polygon(num, ff, Odd, e1->foregr);
+}