There is 1 other file named dash2.for in the archive. Click here to see a list.
CC DASH1 and DASH2 by Joe Smith, Feb 77
C Subroutine DASH1 (XFROM, YFROM, XTO, YTO, DASH)
C This routine is similair to DASHLN.
C Draws a dashed line from (XFROM,YFROM) to (XTO,YTO)
C with dashes of length DASH. All arguments are input parameters
C and are not changed. If DASH is negative or zero, DASH1 will
C move to (XTO,YTO) with the pen up.
C Comparison with DASHLN
C DASHLN will always move with the pen up to the starting position
C and then lower the pen. It will do this even if the pen is in
C the correct position. Repeated raising and lowering of the pen
C will damage it. DASHLN calculates the number of dashes required
C to travel to the ending position and then rounds down to the
C next lower even integer. This is so that the last dash, which
C connects to (XTO,YTO) will be visible even if it has to be up to
C twice as long as the other dashes. If the distance between
C (XFROM,YFROM) and (XTO,YTO) is less than twice the DASH length,
C DASHLN will draw a solid line.
C Differences in DASH1
C DASH1 makes all the dashes the same size, even if the last one
C is not visible. It remembers how much of the last dash was
C plotted and whether the pen was down or up.
C If XFROM is 999.0, DASH1 will use the current X position.
C If YFROM is 999.0, DASH1 will use the current Y position.
C If either XFROM or YFROM is not 999.0, DASH1 will move to the
C starting position with the pen up, and start a visible dash.
C If both XFROM and YFROM are 999.0, DASH1 will not lift and
C drop the pen, but will continue the dash it started, heading
C off in the new direction. This allows smooth curves, such
C as sine waves, to be plotted with dashed lines.
C Subroutine DASH2 (XFROM, YFROM, XTO, YTO, DASH, DDOT)
C This routine is similair to DASH1, except that the distance
C for the pen to be up is DDOT and need not be the same as
C the distance for the pen to be down (DASH).
C All arguments are input parameters and are not changed.
C If DASH is negative or zero, DASH2 will move to (XTO,YTO)
C with the pen up. If DDOT is zero, DASH2 will draw a solid
C line from (XFROM,YFROM) to (XTO,YTO). If DDOT is negative,
C DASH2 will draw a line of alternating dashes and dots.
C The length of the spaces and the dots is the absolute value
C of DDOT. For example, if DASH = +0.4 and DDOT = -0.2,
C DASH2 will draw a dash of 0.4 inches, a space of 0.2 inches,
C a dot of 0.2 inches, and a space of 0.2 inches. This pattern
C of (DASH, SPACE, DOT, SPACE) will be repeated every inch.
C (0.4 + 0.2 + 0.2 + 0.2 = 1.0).
C Like DASH1, DASH2 will continue the pattern if XFROM and YFROM
C are both 999.0
SUBROUTINE DASH2 (XFROM, YFROM, XTO, YTO, DASH, DDOT)
SPACE=DDOT ! SPACING BETWEEN DASHES
IF (DDOT .GT. 0.0) GOTO 10 ! DASH, SPACE, DASH, SPACE
SPACE=-DDOT ! POSITIVE DISTANCE
DOT=SPACE ! DASH, SPACE, DOT, SPACE
ENTRY DASH1 (XFROM, YFROM, XTO, YTO, DASH) ! LIKE DASHLN
DOT=DASH ! MAKE EQUAL SPACING
10 IF (DASH .LE. 0.0) GOTO 40 ! MOVE WITH PEN UP
CALL WHERE (XOLD, YOLD, TRAVEL) ! FIND OUT WHERE WE ARE
IF (XFROM .NE. 999.0) XOLD=XFROM ! USE OLD VALUE IF 999
IF (YFROM .NE. 999.0) YOLD=YFROM ! CONTINUE CURVE IF BOTH
IF (XFROM .EQ. 999.0 .AND. YFROM .EQ. 999.0) GOTO 20
MODE=0 ! START A DASH
TOGO=DASH ! DISTANCE TO GO
DISTAN=0.0 ! JUST STARTED
CALL PLOT (XOLD, YOLD, 3) ! MOVE TO STARTING POSITION
20 IF (SPACE .EQ. 0.0) GOTO 50 ! MOVE WITH PEN DOWN
30 XDIST=XTO-XOLD ! MAIN LOOP
YDIST=YTO-YOLD ! FIND DISTANCE TO MOVE
STEP=SQRT( XDIST*XDIST + YDIST*YDIST )
IF (STEP+DISTAN .LE. TOGO) GOTO 70 ! PLOT THE REST OF THE DASH
TRAVEL=(TOGO-DISTAN)/STEP ! 0 < TRAVEL < 1.0
XOLD=TRAVEL*XDIST+XOLD ! FIND POINT TO CHANGE PEN
CALL PLOT (XOLD, YOLD, (MODE.AND.1)+2) ! MOVE TO THAT POINT
MODE=MODE+1 !0=DASH, 1=SPACE, 2=DOT, 3=SPACE
TOGO=SPACE ! ASSUME SO
IF (MODE .EQ. 2) TOGO=DOT
IF (MODE .EQ. 4) MODE=0 ! MODE HAS A CYCLE OF 4
IF (MODE .EQ. 0) TOGO=DASH
DISTAN=0.0 ! DISTANCE TRAVELLED IN THIS MODE
GOTO 30 ! LOOP UNTIL WE GET TO XTO,YTO
40 MODE=1 ! PEN UP
50 MODE=0 ! PEN DOWN
STEP=0.0 ! SO DISTAN WILL BE 0.0
70 XOLD=XTO ! DON'T CHANGE XTO AND YTO
CALL PLOT (XOLD, YOLD, (MODE.AND.1)+2) ! LAST MOVE
DISTAN=DISTAN+STEP ! REMEMBER DISTAN AND MODE FOR NEXT TIME
RETURN ! AFTER GOING TO XTO,YTO