setlinestyle

Syntax

#include <graphics.h>
void setlinestyle(int linestyle, unsigned upattern, int thickness);

Description

setlinestyle sets the style for all lines drawn by line, lineto, rectangle, drawpoly, and so on.

The linesettingstype structure is defined in graphics.h as follows:

struct linesettingstype {
   int linestyle;
   unsigned upattern;
   int thickness;
};

linestyle specifies in which of several styles subsequent lines will be drawn (such as solid, dotted, centered, dashed). The enumeration line_styles, which is defined in graphics.h, gives names to these operators:

Name	Value	Description
SOLID_LINE	0	Solid line
DOTTED_LINE	1	Dotted line
CENTER_LINE	2	Centered line
DASHED_LINE	3	Dashed line
USERBIT_LINE	4	User-defined line style

thickness specifies whether the width of subsequent lines drawn will be normal or thick.

Name	Value	Description
NORM_WIDTH	1	1 pixel wide
THICK_WIDTH	3	3 pixels wide

upattern is a 16-bit pattern that applies only if linestyle is USERBIT_LINE (4). In that case, whenever a bit in the pattern word is 1, the corresponding pixel in the line is drawn in the current drawing color. For example, a solid line corresponds to a upattern of 0xFFFF (all pixels drawn), and a dashed line can correspond to a upattern of 0x3333 or 0x0F0F. If the linestyle parameter to setlinestyle is not USERBIT_LINE (in other words, if it is not equal to 4), you must still provide the upattern parameter, but it will be ignored.

Note: The linestyle parameter does not affect arcs, circles, ellipses, or pie slices. Only the thickness parameter is used.

Return Value

If invalid input is passed to setlinestyle, graphresult returns -11, and the current line style remains unchanged.

See also

arc

bar3d

bar

circle

drawpoly

ellipse

getlinesettings

graphresult

line

linerel

lineto

pieslice

rectangle

Example

/* setlinestyle example */ 

#include <graphics.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <conio.h>

/* the names of the line styles supported */
char *lname[] = { "SOLID_LINE", "DOTTED_LINE", "CENTER_LINE", "DASHED_LINE", "USERBIT_LINE" };

int main(void)
{
   /* request autodetection */
   int gdriver = DETECT, gmode, errorcode;
   int style, midx, midy, userpat;
   char stylestr[40];

   /* initialize graphics and local variables */
   initgraph(&gdriver, &gmode, "");


   /* read result of initialization */
   errorcode = graphresult();
   if (errorcode != grOk) {  /* an error occurred */
      printf("Graphics error: %s\n", grapherrormsg(errorcode));
      printf("Press any key to halt:");
      getch();
      exit(1);               /* terminate with an error code */
   }

   midx = getmaxx() / 2;
   midy = getmaxy() / 2;

   /* a user-defined line pattern */
   /* binary: "0000000000000001" */
   userpat = 1;
   for (style=SOLID_LINE; style<=USERBIT_LINE; style++)

   {
      /* select the line style */
      setlinestyle(style, userpat, 1);

      /* convert style into a string */
      strcpy(stylestr, lname[style]);

      /* draw a line */
      line(0, 0, midx-10, midy);


      /* draw a rectangle */
      rectangle(0, 0, getmaxx(), getmaxy());

      /* output a message */
      outtextxy(midx, midy, stylestr);

      /* wait for a key */
      getch();
      cleardevice();
   }

   /* clean up */
   closegraph();

   return 0;
}