svg_legend.c File Reference

Functions for drawing legends to SVG plots. More...

#include "libtpcsvg.h"

Go to the source code of this file.

Functions
void	svg_init_legends (SVG_LEGENDS *legends)
void	svg_legend_empty (SVG_LEGENDS *legends)
int	svg_legend_add (SVG_LEGENDS *legends, const int plot_type, const int symbol_type, const svgSymbolFill symbol_fill, const int color, const char *text)
int	svg_create_legends (FILE *fp, struct svg_viewports *vp, SVG_LEGENDS *legends, char *errmsg, int verbose)
char *	svg_str_encode (const char *s)

Variables
int	SVG_INLINE

Detailed Description

Functions for drawing legends to SVG plots.

Author

Vesa Oikonen

Definition in file svg_legend.c.

Function Documentation

svg_create_legends()

int svg_create_legends	(	FILE *	fp,
		struct svg_viewports *	vp,
		SVG_LEGENDS *	legends,
		char *	errmsg,
		int	verbose )

Create SVG plot legends.

Returns

Returns 0 if successful, <>0 in case of error.

Parameters

fp	SVG graphics file pointer.
vp	Struct containing the viewport sizes.
legends	Pointer to struct containing legends.
errmsg	Char pointer to string (at least of length 128) where possible error description is copied; set to NULL if not necessary.
verbose	Verbose level; if zero, then nothing is printed to stderr or stdout.

Definition at line 76 of file svg_legend.c.

  {
  char tmp[1024], line[128], ilc[9];
  double xpos, ypos, ygap, size=100.0, trgsize=140.0, circsize=120.0;
  int ti, len, maxlen, text_space;
  const int defNr=24;
//  const double hrratio=1.80; // average character height/width 
  const double hrratio=1.20; // average character height/width 
 
  if(verbose>0) printf("%s(fp, vp, legends, errmsg, %d)\n", __func__, verbose);
 
  /* Check the input */
  if(vp->label_area_viewport.is==0) return(0);
  if(legends==NULL || legends->n<1) return(0);
  if(fp==NULL) {
    if(errmsg!=NULL) sprintf(errmsg, "file was closed too early");
    return(1);
  }
 
  if(SVG_INLINE) strcpy(ilc, "svg:"); else strcpy(ilc, "");
 
  /* Create a new viewport for plot legends */
  strcpy(tmp, "\n  <!-- Legends viewport -->\n");
  sprintf(line, "  <%ssvg x=\"%dpx\" y=\"%dpx\" width=\"%dpx\" height=\"%d\"",
    ilc, vp->label_area_viewport.x, vp->label_area_viewport.y,
    vp->label_area_viewport.w, vp->label_area_viewport.h); strcat(tmp, line);
  sprintf(line, "\n      viewBox=\"0 0 %d %d\"",
    vp->label_area_viewport.w, vp->label_area_viewport.h); strcat(tmp, line);
  strcat(tmp, "\n      preserveAspectRatio=\"xMidYMid meet\"");
  strcat(tmp, ">\n");
  if(svg_write(fp, tmp, errmsg, verbose-5)!=0) {return(4);}
 
 
#if(0) // during testing show the vieport with background color
  sprintf(tmp, "    <%srect width=\"%dpx\" height=\"%dpx\" stroke=\"none\" fill=\"red\" fill-opacity=\"0.3\" />\n",
    ilc, vp->label_area_viewport.w, vp->label_area_viewport.h);
  if(svg_write(fp, tmp, errmsg, verbose-5)!=0) {return(99);}
#endif
 
  /* Set the space for legend text */
  text_space=(8*vp->label_area_viewport.w)/10;
 
  /* Determine font size for legends */
  /* first, based on legend nr */
  ti=legends->n; if(ti<defNr) ti=defNr;
  vp->label_area_viewport.chr_size=
    (double)vp->label_area_viewport.h/(double)(ti+1);
  //printf("vp->label_area_viewport.chr_size := %d\n", vp->label_area_viewport.chr_size);
  /* then, make smaller based on max length, if necessary */
  ti=0; maxlen=len=strlen(legends->l[ti].text);
  for(ti=1; ti<legends->n; ti++) {
    len=strlen(legends->l[ti].text); if(len>maxlen) maxlen=len;}
  //printf("legend max length := %d\n", maxlen);
  if(vp->label_area_viewport.chr_size*maxlen>hrratio*(double)text_space)
    vp->label_area_viewport.chr_size=hrratio*(double)text_space/(double)maxlen;
  //printf("vp->label_area_viewport.chr_size := %d\n", vp->label_area_viewport.chr_size);
  /* Set line gap, if there is space for that */
  ygap=0; if(legends->n<=2*defNr/3) ygap=vp->label_area_viewport.chr_size/3;
 
  /* Write legend texts as a group */
  xpos=(double)(vp->label_area_viewport.w - text_space);
  ypos=1.5*(double)vp->label_area_viewport.chr_size;
  sprintf(tmp, "    <%sg", ilc);
  sprintf(line, " font-family=\"Sans-serif\""); strcat(tmp, line);
  sprintf(line, " text-anchor=\"Start\""); strcat(tmp, line);
  sprintf(line, " font-size=\"%d\"", vp->label_area_viewport.chr_size); strcat(tmp, line);
  sprintf(line, " fill=\"black\""); strcat(tmp, line);
  strcat(tmp, ">\n"); 
  if(svg_write(fp, tmp, errmsg, verbose-5)!=0) {return(8);}
  /* Write one legend text at a time */
  for(ti=0; ti<legends->n; ti++) {
    //printf("ti=%d text='%s'\n", ti, legends->l[ti].text);
    sprintf(tmp, "      <%s", ilc);
    sprintf(line, "text x=\"%g\" y=\"%g\"", xpos, ypos); strcat(tmp, line);
    sprintf(line, ">"); strcat(tmp, line);
    char *senc=svg_str_encode(legends->l[ti].text);
    if(senc==NULL) strcat(tmp, legends->l[ti].text); else {strcat(tmp, senc); free(senc);}
    strcat(tmp, "</"); strcat(tmp, ilc); strcat(tmp, "text>\n");
    if(svg_write(fp, tmp, errmsg, verbose-5)!=0) {return(9);}
    ypos+=ygap+(double)vp->label_area_viewport.chr_size;
  }
  sprintf(tmp, "    </%sg>\n", ilc);
  if(svg_write(fp, tmp, errmsg, verbose-5)!=0) {return(10);}
 
  /* Write legend symbols */
  xpos=0.5*(double)(vp->label_area_viewport.w - text_space);
  ypos=1.25*(double)vp->label_area_viewport.chr_size;
  for(ti=0; ti<legends->n; ti++) {
    sprintf(tmp, "    <%sg", ilc);
    sprintf(line, " stroke=\"%s\"", svgColorName(legends->l[ti].color)); strcat(tmp, line);
    sprintf(line, " fill=\"%s\"", svgColorName(legends->l[ti].color)); strcat(tmp, line);
    if(legends->l[ti].symbol_fill==SYMBOLOPEN) sprintf(line, " fill-opacity=\"0.02\"");
    else sprintf(line, " fill-opacity=\"0.92\"");
    strcat(tmp, line);
    sprintf(line, " stroke-width=\"25\""); strcat(tmp, line);
    strcat(tmp, ">\n"); 
    if(svg_write(fp, tmp, errmsg, verbose-5)!=0) {return(8);}
 
    /* Line */
    if(legends->l[ti].plot_type==0 || legends->l[ti].plot_type==1) {
      sprintf(tmp, "      <%sline", ilc);
      sprintf(line, " x1=\"%g\"", 0.25*xpos); strcat(tmp, line);
      sprintf(line, " y1=\"%g\"", ypos); strcat(tmp, line);
      sprintf(line, " x2=\"%g\"", 1.75*xpos); strcat(tmp, line);
      sprintf(line, " y2=\"%g\"", ypos); strcat(tmp, line);
      strcat(tmp, " />\n");
      if(svg_write(fp, tmp, errmsg, verbose-5)!=0) {return(18);}
    }
 
    /* Symbol */
    if(legends->l[ti].plot_type==0 || legends->l[ti].plot_type==2) {
      sprintf(tmp, "      <%suse ", ilc);
      switch(legends->l[ti].symbol_type) {
        case RECTANGLE:
          sprintf(line, "xlink:href=\"#sym-rect\" x=\"%g\" y=\"%g\" width=\"%g\" height=\"%g\"",
            xpos-0.5*size, ypos-0.5*size, size, size);
          break;
        case UPTRIANGLE:
          sprintf(line, "xlink:href=\"#sym-uptr\" x=\"%g\" y=\"%g\" width=\"%g\" height=\"%g\"",
            xpos-0.5*trgsize, ypos-0.5*trgsize, trgsize, trgsize);
          break;
        case DOWNTRIANGLE:
          sprintf(line, "xlink:href=\"#sym-dotr\" x=\"%g\" y=\"%g\" width=\"%g\" height=\"%g\"",
            xpos-0.5*trgsize, ypos-0.5*trgsize, trgsize, trgsize);
          break;
        case DIAMOND:
          sprintf(line, "xlink:href=\"#sym-diam\" x=\"%g\" y=\"%g\" width=\"%g\" height=\"%g\"",
            xpos-0.5*trgsize, ypos-0.5*trgsize, trgsize, trgsize);
          break;
        case LEFTTRIANGLE:
          sprintf(line, "xlink:href=\"#sym-letr\" x=\"%g\" y=\"%g\" width=\"%g\" height=\"%g\"",
            xpos-0.5*trgsize, ypos-0.5*trgsize, trgsize, trgsize);
          break;
        case RIGHTTRIANGLE:
          sprintf(line, "xlink:href=\"#sym-ritr\" x=\"%g\" y=\"%g\" width=\"%g\" height=\"%g\"",
            xpos-0.5*trgsize, ypos-0.5*trgsize, trgsize, trgsize);
          break;
        case CIRCLE:
        default:
          sprintf(line, "xlink:href=\"#sym-circ\" x=\"%g\" y=\"%g\" width=\"%g\" height=\"%g\"",
            xpos-0.5*circsize, ypos-0.5*circsize, circsize, circsize);
          break;
      }
      strcat(tmp, line);
      strcat(tmp, " />\n");
      if(svg_write(fp, tmp, errmsg, verbose-5)!=0) {return(18);}
    }
 
 
    sprintf(tmp, "    </%sg>\n", ilc);
    if(svg_write(fp, tmp, errmsg, verbose-5)!=0) {return(10);}
    ypos+=ygap+(double)vp->label_area_viewport.chr_size;
  } // next legend
 
  /* Close the view port */
  sprintf(tmp, "  </%ssvg>\n", ilc);
  if(svg_write(fp, tmp, errmsg, verbose-5)!=0) {return(9);}
 
  return(0);
}

Referenced by plot_fit_svg(), plot_fitrange_svg(), and plot_svg().

svg_init_legends()

void svg_init_legends

(

SVG_LEGENDS *

legends

)

Initiate SVG plot legends struct contents; call this once before usage

Parameters

legends

Pointer to legends struct

Definition at line 14 of file svg_legend.c.

  {
  legends->_init=1;
  legends->n=0;
  legends->l=NULL;
}

Referenced by plot_fit_svg(), plot_fitrange_svg(), and plot_svg().

svg_legend_add()

int svg_legend_add	(	SVG_LEGENDS *	legends,
		const int	plot_type,
		const int	symbol_type,
		const svgSymbolFill	symbol_fill,
		const int	color,
		const char *	text )

Add information of one legend item to legends struct.

Memory will be allocated here.

Returns

Returns 0 when successful, otherwise <>0.

Parameters

legends	Pointer to legends structure.
plot_type	Plot type: 1=line, 2=symbols, 0=both line and symbols.
symbol_type	Symbol type: RECTANGLE, CIRCLE, UPTRIANGLE, DOWNTRIANGLE, DIAMOND, LEFTTRIANGLE, RIGHTTRIANGLE
symbol_fill	Symbol filling: SYMBOLOPEN, SYMBOLFILLED
color	SVG color index.
text	Pointer to Legend text.

Definition at line 43 of file svg_legend.c.

  {
  if(legends==NULL || legends->_init!=1) return 1;
  if(legends->n==0) legends->l=malloc((legends->n+1)*sizeof(SVG_LEGEND));
  else legends->l=realloc(legends->l, (legends->n+1)*sizeof(SVG_LEGEND));
  if(legends->l==NULL) {legends->n=0; return 2;}
  legends->n++;
  legends->l[legends->n-1].plot_type=plot_type;
  legends->l[legends->n-1].symbol_type=symbol_type;
  legends->l[legends->n-1].symbol_fill=symbol_fill;
  legends->l[legends->n-1].color=color;
  strncpy(legends->l[legends->n-1].text, text, MAX_SVG_LEGEND_LEN);
  legends->l[legends->n-1].text[MAX_SVG_LEGEND_LEN]=(char)0;
  return 0;
}

Referenced by plot_fit_svg(), plot_fitrange_svg(), and plot_svg().

svg_legend_empty()

void svg_legend_empty

(

SVG_LEGENDS *

legends

)

Empty the legends struct contents and free the allocated memory.

Parameters

legends

Pointer to legends struct

Definition at line 26 of file svg_legend.c.

  {
  if(legends==NULL) return;
  if(legends->_init==0 || legends->n<1) return;
  free(legends->l);
  legends->n=0;
}

Referenced by plot_fit_svg(), plot_fitrange_svg(), and plot_svg().

svg_str_encode()

char * svg_str_encode

(

const char *

s

)

Encode special characters for XML, including SVG.

Postcondition

Free the memory of returned string pointer.

Returns

Returns pointer to encoded string. NULL is returned in case of an error, or if encoding is not necessary.

See also

strEncodeForXML

Parameters

s	Pointer to the string to be encoded.

Definition at line 256 of file svg_legend.c.

  {
  if(s==NULL) return(NULL);
  /* Count the characters needing encoding */
  int n=0;
  for(size_t i=0; i<strlen(s); i++) {
    if(s[i]=='&') {n++; continue;}
    if(s[i]=='\'') {n++; continue;}
    if(s[i]=='\"') {n++; continue;}
    if(s[i]=='<') {n++; continue;}
    if(s[i]=='>') {n++; continue;}
  }
  if(n==0) return(NULL);
  /* Allocate memory for new string (one char to max 6 chars) */
  n*=5; n+=strlen(s);
  char *ns=(char*)malloc(n*sizeof(char));
  if(ns==NULL) return(NULL);
  /* Process the string */
  for(int i=0; i<n; i++) ns[i]=(char)0;
  for(size_t i=0; i<strlen(s); i++) {
    if(s[i]=='&') {strcat(ns, "&amp;"); continue;}
    if(s[i]=='\'') {strcat(ns, "&apos;"); continue;}
    if(s[i]=='\"') {strcat(ns, "&quot;"); continue;}
    if(s[i]=='<') {strcat(ns, "&lt;"); continue;}
    if(s[i]=='>') {strcat(ns, "&gt;"); continue;}
    ns[strlen(ns)]=s[i];
  }
  return(ns);
}

Referenced by svg_create_legends(), and svg_write_tac().

Variable Documentation

SVG_INLINE

int SVG_INLINE

extern

Write inline SVG (1) or separate SVG file (0)

Definition at line 12 of file svg_file.c.