/* XFig has three spline formats. * * Approximated. Can be approximated by Bezier curves whose * end points are the mid point between the spline's control points, * and whose control points lie two thirds of the way from the Bezier's * end points to the XFig control point. Open curves start with a straight * line segment from the first point to the midpoint of the first two points, * and end similarly. * * Interpolated. Can be approximated by Bezier curves whose * end points are the spline's control points, and whose control points * are formed as follows. The Bezier curve from x(i) to x(i+1) has control * points x(i)+0.25*(x(i+1)-x(i-1)) and x(i+1)-0.25*(x(i+2)-x(i)). * Open curves start with the first control point lying on the end point, * and end similarly. * * X-spline. Too complicated to describe / code here! * * All two point splines (including X-splines) are straight lines. * * Well, it turns out that the above theories, found using Google, are * very gross approximations. For the moment they can stay. */ #include #include /* exit() */ #include #include #include #include "fig2pdf.h" void write_arrow(struct arrow *a,double x,double y,double dx,double dy, int colour,char *buffer, int *i); void write_spline(char *p){ int i,off,pt,inc,open,filled; int obj,sub,line_style,thickness,pen_colour,fill_colour,depth; int pen_style,fill,cap,arrow_f,arrow_b,npoints,debug; double style,width; double *x,*y,*s; struct arrow forward,backward; char *f,*buffer; unsigned buff_len=1000; buffer=malloc(buff_len); debug=flags&DEBUG_MASK; i=sscanf(p,"%d %d %d %d %d %d %d %d %d %lf %d %d %d %d %n", &obj,&sub,&line_style,&thickness,&pen_colour,&fill_colour, &depth,&pen_style,&fill,&style,&cap, &arrow_f,&arrow_b,&npoints,&off); if (i!=14){ fprintf(stderr,"Error parsing spline object\n"); exit(1); } if (arrow_f){ p=fgets(buffer,180,fig); i=sscanf(p,"%d %d %lf %lf %lf %n",&forward.type,&forward.style, &forward.thickness,&forward.width,&forward.height,&off); } if (arrow_b){ p=fgets(buffer,180,fig); i=sscanf(p,"%d %d %lf %lf %lf %n",&backward.type,&backward.style, &backward.thickness,&backward.width,&backward.height,&off); } open=1; /* An open curve */ if ((sub==1)||(sub==3)) open=0; /* A closed curve */ filled=0; if ((fill>=0)&&(fill<=40)) filled=1; else if (fill!=-1) fprintf(stderr,"Unsupported fill type ignored\n"); /* Read points as doubles, though are stored as ints */ x=malloc(npoints*sizeof(double)); y=malloc(npoints*sizeof(double)); if (debug>1) fprintf(stderr,"Reading spline of %d points\n",npoints); for(pt=0;pt3)&&(npoints>2)){ fprintf(stderr,"Unsupported spline subtype skipped\n"); return; } /* Scale everything */ for(pt=0;pt1) width=(thickness-1)*72.0/80; else width=thickness*72.0/160; if (arrow_f){ forward.width*=72.0/1200; forward.height*=72.0/1200; forward.thickness*=72.0/80; } if (arrow_b){ backward.width*=72.0/1200; backward.height*=72.0/1200; backward.thickness*=72.0/80; } style*=72.0/80; if ((filled==0)&&(width==0)) return; /* Nothing to do */ /* Update bounding box as necessary */ for(pt=0;ptMAX_COL)) pen_colour=-1; if (pen_colour==-1) i+=sprintf(buffer+i," 0 0 0 RG"); else if (fig_colours[pen_colour]) i+=sprintf(buffer+i," %s RG",fig_colours[pen_colour]); else fprintf(stderr,"Invalid pen colour %d\n",pen_colour); f=fill_col(fill_colour,fill); if (f) i+=sprintf(buffer+i," %s rg",f); i+=sprintf(buffer+i," %.2f w\n",width); if (cap) i+=sprintf(buffer+i,"%d J\n",cap); /* 0 butt, 1 round, 2 projecting, same as PDF */ if (line_style>0) write_dash(line_style,style,buffer,&i); if (npoints==2){ /* We have a simple straight line, which can't be filled */ if (width==0) return; i+=sprintf(buffer+i,"%.2f %.2f %.2f %.2f l\n",x[0],y[0],x[1],y[1]); i+=sprintf(buffer+i,"h S Q\n"); if (arrow_f) write_arrow(&forward,x[1],y[1], x[1]-x[0],y[1]-y[0], pen_colour,buffer,&i); if (arrow_b) write_arrow(&backward,x[0],y[0], x[0]-x[1], y[0]-y[1], pen_colour,buffer,&i); OBJ_PRN("<> stream\n%s\nendstream\nendobj\n\n",i,buffer); add_obj(cref,depth); return; } if ((sub==0)||(sub==1)){ /* Approximated splines */ if (open) i+=sprintf(buffer+i,"%.2f %.2f m %.2f %.2f l\n",x[0],y[0], 0.5*(x[0]+x[1]),0.5*(y[0]+y[1])); else i+=sprintf(buffer+i,"%.2f %.2f m\n",0.5*(x[0]+x[1]), 0.5*(y[0]+y[1])); for(pt=1;pt(buff_len-500)){ buff_len+=2000; buffer=realloc(buffer,buff_len); } } if (open) i+=sprintf(buffer+i,"%.2f %.2f l\n",x[npoints-1],y[npoints-1]); else{ i+=sprintf(buffer+i,"%.2f %.2f %.2f %.2f %.2f %.2f c\n", x[npoints-2]/6+5*x[npoints-1]/6, y[npoints-2]/6+5*y[npoints-1]/6, x[0]/6+5*x[npoints-1]/6,y[0]/6+5*y[npoints-1]/6, 0.5*(x[npoints-1]+x[0]),0.5*(y[npoints-1]+y[0])); i+=sprintf(buffer+i,"%.2f %.2f %.2f %.2f %.2f %.2f c h\n", x[npoints-1]/6+5*x[0]/6, y[npoints-1]/6+5*y[0]/6, x[1]/6+5*x[0]/6,y[1]/6+5*y[0]/6, 0.5*(x[0]+x[1]),0.5*(y[0]+y[1])); } } else if ((sub==2)||(sub==3)){ /* Interpolated splines */ i+=sprintf(buffer+i,"%.2f %.2f m\n",x[0],y[0]); if (open) i+=sprintf(buffer+i,"%.2f %.2f ",x[0],y[0]); else i+=sprintf(buffer+i,"%.2f %.2f ",x[0]+0.25*(x[1]-x[npoints-1]), y[0]+0.25*(y[1]-y[npoints-1])); i+=sprintf(buffer+i,"%.2f %.2f %.2f %.2f c\n",x[1]-0.25*(x[2]-x[0]), y[1]-0.25*(y[2]-y[0]),x[1],y[1]); for(pt=2;pt(buff_len-500)){ buff_len+=2000; buffer=realloc(buffer,buff_len); } } if (open){ i+=sprintf(buffer+i,"%.2f %.2f %.2f %.2f %.2f %.2f c\n", x[pt-1]+0.25*(x[pt]-x[pt-2]),y[pt-1]+0.25*(y[pt]-y[pt-2]), x[pt],y[pt],x[pt],y[pt]); } else{ i+=sprintf(buffer+i,"%.2f %.2f %.2f %.2f %.2f %.2f c\n", x[pt-1]+0.25*(x[pt]-x[pt-2]),y[pt-1]+0.25*(y[pt]-y[pt-2]), x[pt]-0.25*(x[0]-x[pt-1]),y[pt]-0.25*(y[0]-y[pt-1]), x[pt],y[pt]); pt++; i+=sprintf(buffer+i,"%.2f %.2f %.2f %.2f %.2f %.2f c h\n", x[pt-1]+0.25*(x[0]-x[pt-2]),y[pt-1]+0.25*(y[0]-y[pt-2]), x[0]-0.25*(x[1]-x[pt-1]),y[0]-0.25*(y[1]-y[pt-1]), x[0],y[0]); } } if (filled) if (width==0) i+=sprintf(buffer+i,"f\n"); else i+=sprintf(buffer+i,"B\n"); else i+=sprintf(buffer+i,"S\n"); if (sub==0){ if (arrow_f) write_arrow(&forward,x[npoints-1],y[npoints-1], x[npoints-1]-x[npoints-2], y[npoints-1]-y[npoints-2], pen_colour,buffer,&i); if (arrow_b) write_arrow(&backward,x[0],y[0], x[0]-x[1], y[0]-y[1], pen_colour,buffer,&i); } else if (sub==2){ if (arrow_f) write_arrow(&forward,x[npoints-1],y[npoints-1], x[npoints-1]- (x[npoints-2]+0.25*(x[npoints-1]-x[npoints-3])), y[npoints-1]- (y[npoints-2]+0.25*(y[npoints-1]-y[npoints-3])), pen_colour,buffer,&i); if (arrow_b) write_arrow(&backward,x[0],y[0], x[0]-(x[1]-0.25*(x[2]-x[0])), y[0]-(y[1]-0.25*(y[2]-y[0])), pen_colour,buffer,&i); } i+=sprintf(buffer+i,"Q"); OBJ_PRN("<> stream\n%s\nendstream\nendobj\n\n",i,buffer); add_obj(cref,depth); free(buffer); free(x); free(y); free(s); }