setwritemode example in c

Header file:

    graphics.h

Synopsis:

      void setwritemode(int mode);

     

Description:

     setwritemode() sets the current writing mode for line drawing.  Mode can be COPY_PUT or XOR_PUT.

COPY_PUT - overwrites with the line on screen

XOR_PUT  - uses XOR command to mix line with the screen

setwritemode function in c graphics

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

  int main() {
        /* request auto detection */
        int graphicDriver = DETECT, graphicMode, err;

        /* initialize graphics and local variables */
        initgraph(&graphicDriver, &graphicMode,
                                        "C:/TURBOC3/BGI");

        /* read result of initialization */
        err = graphresult();

        if (err != grOk) {
                /* an error occurred */
                printf("Graphics error: %s\n",
                                grapherrormsg(err));
                getch();
                return 0;
        }

        /* select XOR drawing mode */
        setwritemode(XOR_PUT);

        /* draw a line */
        line(0, 0, getmaxx(), getmaxy());
        getch();

        /* erase the line by drawing over it */
        line(0, 0, getmaxx(), getmaxy());
        getch();

        /* select overwrite drawing mode */
        setwritemode(COPY_PUT);

        /* draw a line */

        line(0, 0, getmaxx(), getmaxy());

        /* clean up */

        getch();

        closegraph();

        return 0;

  }

Output: (setwritemode built-in function in c graphics.h)

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