/************************************************************************/
/* Draw a triangle with dot-dashed lines                                */
/************************************************************************/

pattern_triag()
        {
        #define DOT_DASH        0x30FC
        #define WHITE           15
        slow_pattern_line(420,0,0,200,WHITE,DOT_DASH);
        slow_pattern_line(0,200,639,200,WHITE,DOT_DASH);
        slow_pattern_line(420,0,639,200,WHITE,DOT_DASH);
        }

/************************************************************************/
/* Draw a box with checkerboard pattern using patterned lines           */
/************************************************************************/

checkers()
        {
        #define EVEN_DOTS       0xAAAA
        #define ODD_DOTS        0x5555
        #define WHITE           15
        int     i;
        for (i = 0; i < 100; i += 2)
                {
                slow_pattern_line(300,i  ,500,i  ,WHITE,EVEN_DOTS);
                slow_pattern_line(300,i+1,500,i+1,WHITE, ODD_DOTS);
                }
        }