The appearance of the text is affected by several set-able parameters. The size of the letters is determined by set(FONTWIDTH , size_in_cm); while the ratio of height to width is set using set(FONTASPECT , height_div_width);. Alternatively, the size of the text can be changed from its current value by using set(FONTMULT , multiplier);. The spacing between letters can be modified using set(FONTSPACE , space_in_cm);. The text is ordinarily printed horizontally but this may be changed by using set(FONTDIR , angle_in_deg);. The width of the line used to draw the text is set using set(LINEWIDTH , width); and the colour is set using set(LINECOLOUR , colour_number );. The text is printed using Hershey stroked fonts. There are two available font families simplex and complex. The complex font is chosen using set(FONT , COMPLEX);. Greek and Italic text is selected by using special characters in the text string. Thus Greek may be selected by enclosing a string with '!' as in '!abc! while italics are selected using '#'. Super and sub scripts are handled in the same way by enclosing the super/sub script with '∧' or '_' respectively. The position and size of the super/sub script relative to ordinary text may be modified using the set(SCRIPTSCALE , ratio); and set(SCRIPTSHIFT , fraction ); commands respectively. Characters from the symbol font may be included in the text string by enclosing the symbol number with '$'.
The various text possibilities are explored in the two following demo files. The third demo file is a table of all the available text characters included in the font files.
/* This file illustrates some of the capabilities of the */
/* text() command to annotate figures */
/* Several fonts are available including full Greek. */
/* Text can be any size, orientation and colour. */
#include <splot.h>
main()
{
text(2.63,23,"The default position for the next line");
/* change to complex font for next line */
set(FONT,COMPLEX);
text("right below the previous line");
set(FONT,SIMPLEX);
text("There is a complete set of Greek characters");
text("!abcdefghijklmnopqrstuvxyz!");
set(FONT,COMPLEX);
text("!ABCDEFGHIJKLMNOPQRSTUVWXYZ!");
set(FONT,SIMPLEX);
set(LINECOLOUR,GREEN);
/* optional change of script scale and position */
set(SCRIPTSCALE,1);
set(SCRIPTSHIFT,1);
text("Here are ^super^ and _sub_ scripts");
set(LINECOLOUR,RED);
text("and #Italics# in different colours");
set(LINECOLOUR,BLACK);
text("Letters can be large, small, tall, short");
text("fat, thin, vertical and angled.");
set(FONTMULT,2);
text(2.94,9.56,"Large");
set(FONTMULT,0.30);
text(8.90,9.71,"small");
set(FONTWIDTH,1.0);
set(FONTASPECT,3);
text(13.10,9.71,"Tall");
set(FONTASPECT,0.5);
text(17.05,9.71,"Short");
set(FONTASPECT,2);
set(LINEWIDTH,0.01);
text(2.94,7.29,"Thin");
set(LINEWIDTH,0.2);
text(9.02,7.29,"Fat");
set(LINEWIDTH,0.05);
set(FONTDIR,90);
text(3.63,1.26,"Vertical");
set(FONTDIR,130);
text(11.28,1.44,"Angled");
}
/* This file illustrates some of the capabilities of the */
/* text() command to annotate figures */
#include <splot.h>
main()
{
text(2,23,"The spacing between letters can be changed");
set(FONTSPACE,0.5);
text("to be further apart than usual");
set(FONTSPACE,-0.2);
text("or closer together.");
set(FONTSPACE,0);
text("The size and position of super/sub scripts can");
text(2,17.38,"be varied as in");
set(SCRIPTSHIFT,0.7);
set(SCRIPTSCALE,0.5);
text(8.94,17.38,"X_1_\b^2^,");
set(SCRIPTSHIFT,1.0);
set(SCRIPTSCALE,0.7);
text(10.19,17.38,"X_1_\b^2^,");
set(SCRIPTSHIFT,1.5);
set(SCRIPTSCALE,1.0);
text(11.4,17.38,"X_1_\b^2^.");
text(2.10,15.81,"Note how the superscript was placed above");
text("the subscript using the backspace char \\b.");
text("Enter degree sign using '<ALT X> 127'");
text("Use a \\ before special characters: \_\^\$\#\!\"");
text("Symbols: $0 1 2 3 4 5 6 7 8 9 : ; < = > $");
text(2,8,"The default text insertion point is LEFT");
text(17,6,"but can be set to RIGHT",RIGHT);
text(10,4,"Or CENTER",CENTER);
}
/* This file displays all the available characters */
#include <splot.h>
#define ROMAN 1
#define GREEK 0
#define ITALIC 0
int i,j;
char c[10];
main()
{
set(PAGEROT,ON);
#if ROMAN
text(13.67,19.14,"Roman",CENTER);
text(7.5,18,"Simplex",CENTER);
text(19,18,"Complex",CENTER);
gsave();
scale(1.2,1.2);
translate(1,-11);
set(FONTWIDTH,0.5);
set(FONTASPECT,1.5);
table(0);
translate(10,0);
set(FONT,COMPLEX);
table(0);
set(FONT,SIMPLEX);
#endif
#if GREEK
text(13.67,19.14,"Greek",CENTER);
text(7.5,18,"Simplex",CENTER);
text(19,18,"Complex",CENTER);
gsave();
scale(1.2,1.2);
translate(1,-11);
set(FONTWIDTH,0.5);
set(FONTASPECT,1.5);
table(1);
translate(10,0);
set(FONT,COMPLEX);
table(1);
set(FONT,SIMPLEX);
#endif
#if ITALIC
text(7.5,18,"Italics Simplex/Complex",CENTER);
text(19,18,"Symbols",CENTER);
gsave();
scale(1.2,1.2);
translate(1,-11);
set(FONTWIDTH,0.5);
set(FONTASPECT,1.5);
table(2);
translate(10,0);
table(3);
#endif
grestore();
}
table(int special)
{
/* label rows and columns */
c[1] = '\0';
for (i = 0; i < 10;i++)
{
c[0] = '0' + i;
tputs(2 + i * 0.7,24.5,c,0);
}
c[0] = ' ';
c[2] = '0';
c[3] = '\0';
for (j = 3;j < 10;j++)
{
c[1] = '0' + j;
tputs(0,26 - j,c,0);
}
c[0] = '1';
c[2] = '0';
c[3] = '\0';
for (j = 10;j < 13;j++)
{
c[1] = '0' + j - 10;
tputs(0,26 - j,c,0);
}
/* prepend each char with '\' so that even special chars get printed */
c[0] = '\\';
c[2] = '\0';
box(1.29,23.77,9.07,13.36);
stroke();
/* fill in table */
for (j = 3;j < 13;j++)
{
for (i = 0; i < 10;i++)
{
c[1] = j * 10 + i;
if (c[1] == 'b')
tputs(2 + i * 0.7,26 - j,"b",special);
else
tputs(2 + i * 0.7,26 -j,c,special);
}
}
}
tputs(double x,double y,char *c,int special)
{
char tmp[10];
switch(special)
{
case 0:
text(x,y,c);
break;
case 1:
/* greek */
strcpy(tmp,"!");
strcat(tmp,c);
strcat(tmp,"!");
text(x,y,tmp);
break;
case 2:
/* italics */
strcpy(tmp,"#");
strcat(tmp,c);
strcat(tmp,"#");
text(x,y,tmp);
break;
case 3:
/* symbols */
strcpy(tmp,"$");
strcat(tmp,c);
strcat(tmp,"$");
text(x,y,tmp);
break;
}
}